Need Help For Below Research In The APA Format
A METHODOLODY TOWARD SECURITY EFFECTIVENESS FOR CRITICAL INFRASTRUCTURE AND DEPENDENT RESOURCES
by Latechia White
B.S. in Electrical Engineering, December 1995, Howard University M.S. in Electrical Engineering, May 2006, The George Washington University
A Praxis submitted to
The Faculty of The School of Engineering and Applied Science
of The George Washington University in partial satisfaction of the requirements for the degree of Doctor of Engineering
January 19, 2018
Praxis directed by
Timothy J. Eveleigh Professorial Lecturer of Engineering Management and Systems Engineering
Bereket Tanju
Professorial Lecturer of Engineering Management and Systems Engineering
ProQuest Number:
All rights reserved
INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted.
In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed,
a note will indicate the deletion.
ProQuest
Published by ProQuest LLC ( ). Copyright of the Dissertation is held by the Author.
All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code
Microform Edition © ProQuest LLC.
ProQuest LLC. 789 East Eisenhower Parkway
P.O. Box 1346 Ann Arbor, MI 48106 - 1346
10743940
10743940
2018
ii
The School of Engineering and Applied Science of The George Washington University certifies
that Latechia White has passed the Final Examination for the degree of Doctor of Engineering as
of January 3, 2018. This is the final and approved form of the Praxis.
A METHODOLODY TOWARD SECURITY EFFECTIVENESS FOR CRITICAL INFRASTRUCTURE AND DEPENDENT RESOURCES
Latechia White
Praxis Research Committee:
Timothy J. Eveleigh, Professorial Lecturer of Engineering Management and Systems Engineering, Praxis Co-Director Bereket Tanju, Professorial Lecturer of Engineering Management and Systems Engineering, Praxis Co-Director E. Lile Murphree, Professor Emeritus of Engineering Management and Systems Engineering, Committee Member Amir Etemadi, Assistant Professor of Engineering and Applied Science, Committee Member Barry C. Ezell, Chief Scientist and Research Associate Professor, Committee Member
iii
© Copyright 2018 by Latechia White All rights reserved
iv
DEDICATION
This research is dedicated to Critical Infrastructure (CI) owner/operators and national security and
medical professionals seeking to do more to protect and maintain our nation’s CIs and dependent
resources in an effort to preserve public health and demonstrate emergency preparedness.
v
ACKNOWLEDGMENTS
“If ye have faith as a grain of a mustard seed, ye shall say unto this mountain, Remove hence to
yonder place; and it shall remove; and nothing shall be impossible unto you.”
Matthew 17:20
To my Lord and Savior, because of You I was able. I would like to thank Dr. Timothy
Eveleigh, Dr. Thomas Holzer, and Dr. Bereket Tanju, my advisors at The George Washington
University (GWU), who guided me during my research journey. Their expert feedback and
suggestions helped me achieve one of my life dreams. I am also particularly grateful to Dr.
Shahram Sarkani and Dr. Thomas Mazzuchi, Professors of Engineering Management and
Systems Engineering at the GWU, for establishing such a challenging yet flexible program for full-
time working professionals.
I am thankful to my core group of friends and family who I affectionately call my Prayer
Warriors, whose support and encouragement have been crucial to my motivation and survival in
this program. To my employer, I am grateful for the flexible hours that allowed me to balance my
professional career and academic goals. Additionally, I would like to thank those that took the time
to review my research and provided valuable, constructive feedback. Special thanks to those that
took the time to complete the survey that provided insightful data to my research. Your feedback
will hopefully result in a more secure and resilient world whose reality has become filled with
relentless cyber and physical attacks.
To my husband, lover, and friend, who claims he suffered from my absence during my
journey, who had to fend for himself for breakfast, lunch, and dinner, who tolerated and accepted
my absence and neglect of my domestic responsibilities, who smiled when I offered peanut butter
vi
and jelly as a dinner substitute – thank you for your prayers, patience, enduring love, and support.
Without you this dream would have not been possible. Forever grateful!
vii
ABSTRACT
A Methodolody Toward Security Effectiveness for Critical Infrastructure and Dependent Resources
A successful Denial of Service (DoS) attack on a Critical Infrastructure (CI) can indirectly have
devastating and irreversible effects to those that depend on its services. The mere possibility that
physical destruction or loss of human life can result (indirectly) from a successful attack on a CI
gives reason to re-assess the effectiveness of security measures in place to protect and provide
resiliency. Although existing literature describe numerous approaches to CI interdependency
analyses, it does not sufficiently identify or address a method to dynamically (through scenario
analysis) and proactively evaluate and quantify the relative effectiveness of implemented and/or
proposed security measures against multi-order cascading effects given a CI disruption.
To address the persistent challenge of protecting CIs and maintaining the essential services
that they provide, a method to evaluate security effectiveness with an operational framework is
offered to assist proactive, scenario-based interdependency analysis of CI Protection and
Resiliency (CIP/R). This methodology is provided for CI owners and stakeholders to evaluate their
posture and ultimately make provisions for a more proactive response before potential disaster.
The Bayesian Approach to Security Effectiveness through metrics, modeling and decision-making
(BASE m2d) conceptual framework was developed by this research to address this pervasive
problem. Specifically, this research illustrates the framework by examining multi-order effects on
hospital operations, thereby assessing the likelihood of impact to a patient’s health given a
successful cyber or physical (natural or man-made) attack on a dependent CI.
A survey was provided to medical professionals at 10 different hospitals to help identify current
risk management processes used by the medical professionals to understand, assess, and validate
patient impact given DoS to a dependent CI (Power, Water, and Communications). The
viii
probabilistic Bayesian module allowed for a scenario-based, what-if impact analysis, given limited
available data. This research revealed, despite the known dependence on CIs, no standardized
metrics or processes are used to assess patient impact for risk mitigation given a DoS. Also noted
was a lack of general preparedness, training, and methods of sharing information in the event of a
DoS on a dependent CI. Consequently, the findings of this research resulted in a hybrid,
hierarchical, multi-dimensional approach grounded in systems engineering principles.
ix
TABLE OF CONTENTS
DEDICATION ....................................................................................................................................... IV
ACKNOWLEDGMENTS ........................................................................................................................... V
ABSTRACT ........................................................................................................................................ VII
TABLE OF CONTENTS.......................................................................................................................... IX
LIST OF FIGURES ............................................................................................................................... XII
LIST OF TABLES ............................................................................................................................... XIII
LIST OF ACRONYMS .......................................................................................................................... XIV
CHAPTER 1 - INTRODUCTION ................................................................................................................ 1
1.1 Research Background ....................................................................................................... 5
1.1.1 Overview of CI ............................................................................................................... 5
1.1.2 Healthcare and Public Health ........................................................................................ 7
1.2 Motivation ........................................................................................................................ 10
1.3 Research Problem .......................................................................................................... 11
1.4 Research Objectives ....................................................................................................... 12
1.5 Scope and Limitations ..................................................................................................... 13
1.6 Research Contribution .................................................................................................... 14
1.7 Significance/Implications of Research ............................................................................. 15
1.8 Definitions of Key Concepts ............................................................................................ 17
1.8.1 Security Effectiveness for the Operational Environment ............................................. 17
1.8.2 Hierarchical Holographic Modeling (HHM) .................................................................. 18
1.8.3 Bayesian Belief Network (BBN) ................................................................................... 20
1.8.4 Systems Security Effectiveness Index (SSEI) ............................................................. 21
1.9 Organization and Outline................................................................................................. 22
CHAPTER 2 - LITERATURE REVIEW ..................................................................................................... 24
2.1 Review of Related Works ................................................................................................ 24
2.2 Overview of CIP/R Analysis ............................................................................................ 25
2.3 Approaches to CI Protection & Resiliency (CIP/R) .......................................................... 28
2.3.1 Implementations of Decision Analysis Tools for CIP/R ................................................ 31
x
2.3.2 Implementations of Probabilistic Risk Modeling for CIP/R ........................................... 32
2.4 Approaches to Measuring Security Effectiveness for CI.................................................. 34
2.5 Summary ......................................................................................................................... 34
CHAPTER 3 - RESEARCH METHODOLOGY ............................................................................................ 35
3.1 Research Design ............................................................................................................. 36
3.2 Expert Elicitation ............................................................................................................. 37
3.3 Survey Scale ................................................................................................................... 40
3.4 Expert Elicitation Calibration ........................................................................................... 40
3.5 Survey Instrument ........................................................................................................... 41
3.6 Validity of Survey Instrument ........................................................................................... 43
3.7 Validity of Conceptual Framework ................................................................................... 44
3.8 Data Collection ................................................................................................................ 45
CHAPTER 4 – HOSPITAL CASE STUDY ................................................................................................. 46
4.1 Case Study Background.................................................................................................. 46
4.2 Case Study Application ................................................................................................... 47
4.2.1 Step 1 and 2: Define Operational Environment and Security Goals ........................... 49
4.2.2 Step 3: Identify Dependencies ................................................................................... 50
4.2.3 Step 4: Assess/Measure the Security Posture ........................................................... 50
4.2.4 Step 5: Assess multiple dimensions/perspectives [CI-HHM] ...................................... 53
4.2.5 Step 6: Assess Strength/Weakness [Calculate the SSEI] .......................................... 56
4.2.6 Step 7: Assess Impact Likelihood [Construct the BBN] .............................................. 59
4.2.7 Steps 8-10: Decision Analysis .................................................................................... 65
CHAPTER 5 - DATA ANALYSIS AND RESULTS ....................................................................................... 65
5.1 Analysis Objectives ......................................................................................................... 65
5.2 Demographic Data .......................................................................................................... 66
5.3 Metrics ............................................................................................................................ 68
5.4 Descriptive Data .............................................................................................................. 70
5.5 Reliability and Validity of Survey Instrument ................................................................... 72
5.6 Validity of Conceptual Framework ................................................................................... 74
5.7 Threats to Internal Validity............................................................................................... 75
5.8 Threats to External Validity ............................................................................................. 75
xi
CHAPTER 6 – CONCLUSION ................................................................................................................ 76
6.1 Conclusion with Respect to Study Hypotheses ............................................................... 77
6.2 Conclusion with Respect to Study Questions .................................................................. 77
6.3 Discussion ....................................................................................................................... 78
CHAPTER 7 - FUTURE RESEARCH ....................................................................................................... 81
REFERENCES .................................................................................................................................... 83
APPENDIX A ...................................................................................................................................... 96
APPENDIX B .................................................................................................................................... 102
xii
LIST OF FIGURES
Figure 1. CI Interdependency Multi-order Effects ............................................................................ 9
Figure 2. HHM for Critical Infrastructure or Dependent Resources (CI/DR-HHM) ..........................19
Figure 3. Research Focus Areas ....................................................................................................27
Figure 4. General Flow of BASE m2d Framework .........................................................................48
Figure 5. Simplified BBN ................................................................................................................60
Figure 6. Representation of BASE m2d Model of DoS attack on CIs (w/o SSEI) ...........................62
Figure 7. Representation of SSEI Analysis given DoS Attack on Power CI ...................................63
Figure 8. Survey: Years of Experience in Medical Field ................................................................67
Figure 9. Survey: Medical Field Profession ...................................................................................67
Figure 10. Survey: Experience in Intensive Care Unit (ICU) ..........................................................67
xiii
LIST OF TABLES
Table 1. Healthcare and Public Health Sector CI Dependency (DHS.gov) ..................................... 8
Table 2. Literature Review CI Model Comparative Analysis ...........................................................30
Table 3. Reference Metrics for Critical Infrastructure/Dependent Resource Protection .................52
Table 4. Reference Metrics for Critical Infrastructure/Dependent Resource Resilience .................53
Table 5. CI/DR-HHM SSEI Scoring Scale (by Category) ...............................................................55
Table 6. CI/DR-HHM SSEI Scoring Scale (Total) ...........................................................................56
Table 7. Area of Improvement/Deficiency (Calculated SSEI) .........................................................57
Table 8. Exemplar Stakeholder Question Categories ....................................................................58
xiv
LIST OF ACRONYMS
AHP Analytical Hierarchy Process
BASE m2d Bayesian Approach to Security Effectiveness with metrics, modeling, and decision-
support
BBN Bayesian Belief Network
CI Critical Infrastructure
CIP/R Critical Infrastructure Protection and Resiliency
CPT Conditional Probability Table
DA Decision Analysis
DAG Directed Acyclic Graph
DHS Department of Homeland Security
DOS Denial of Service
DR Dependent Resource
EO Executive Order
GAO Government Accountability Office
HHM Hierarchical Holographic Model
ICU Intensive Care Unit
MAUT Multi-Attribute UtilityTheory
NIPP National Infrastructure Protection Plan
PDD Presidential Decision Directive
PPD Presidential Policy Directive
SCADA Supervisory Control and Data Acquisition
SSEI Systems Security Effectiveness Index
SSP Sector Specific Plan
1
CHAPTER 1 - INTRODUCTION
The definition of security is the state of being free from danger or threat. While this defined state of
being can never be achieved within the cyber domain, the knowledge of one’s security posture (as
it relates to exposure to danger or threat) is paramount to ultimately understanding cyber and/or
physical security and implementing appropriate, timely, and necessary security measures. To that
end, there has been an avalanche of standards, tools, and compliance guidance added to the
cadre of weapons for cyber-warfare; inevitably developed to afford a perceived sense of security
that the devices, networks, systems, and enterprises are secure. Still, organizations’ relative
security posture (i.e. assessed security effectiveness per defined security goals) remains unknown
despite Information Security Professionals having implemented the suggested/recommended
security configurations, tools, policies, and plans in an effort to defend against various known
threats. The risks of misinterpreting one’s security posture can have devastating consequences in
terms of misallocation of resources, loss of revenue, loss of competitive advantage, loss of privacy,
loss of trust, damage to reputation, destruction of property, and in some cases, potential loss of life.
These consequences are amplified when they are associated with the elements of the nation’s
Critical Infrastructures (CIs).
CIs, as defined by the Department of Homeland Security (DHS), are the assets, systems, and
networks, whether physical or virtual, so vital to the United States that their incapacitation or
destruction would have a debilitating effect on security, national economic security, national public
health or safety, or any combination thereof [DHS.gov 2013]. CIs are large, complex, adaptive,
and highly interconnected; they are ripe with potential areas where system knowledge can easily
go unexamined and thus undiscovered. Implementing security measures without considering the
multi-dimensional aspect of interdependencies that are both internal and external to CIs can lead to
2
undesirable consequences. This can ultimately imperil efforts to achieve CI protection goals.
Moreover, goals can be negatively impacted by providing an illusion of acceptable security where
there are actually areas of unacceptable and intolerable risk - in spite of operators having
employed every available tool, policy, and standard. Within the multi-dimensional regions of CIs
there are cyber-based, temporal, geo-spatial, legislative, societal, economic, and stakeholder
attributes that can be explored and considered to uncover unknown insight into a CI and/or
dependent resource’s true security posture.
According to Government Accountability Office (GAO) reports, over the past decade there
has been a sustained increase in malicious penetrations to government information systems [ICS-
CERT 2017, DHS 2016, GAO-15-573T 2015, GAO-12-666T 2012]. In 2012 alone, America's
power, water, financial institutions, nuclear systems, and other key resources have experienced a
52 percent increase in targeted attacks by cyber criminals seeking to gain (or deny) access to the
nation's CI [CERT 2013]. Parties aligned with the Russian government have developed a
cyberweapon (CrashOverride) specifically designed to destroy industrial control systems of CIs.
Considered Stuxnet 2.0, CrashOverride hackers briefly shut down one-fifth of the electric power
generated in Kiev (washingtonpost.com 2017). Recent ransomware cyber-attacks such as
WannaCry and Petya have affected more than 200,000 computers, causing chaos and disruption
for critical infrastructure and dependent resources (CI/DR), including major hospitals, a nuclear
disaster site, and electrical grids (CNET 2017). It was noted by Healthcare Informatics: “this attack
(WannaCry) shows that interconnected devices and systems are vulnerable to attack by nations,
non-state actors, and just plain crooks. An attack of this scope points to the potential for an entirely
different type of damage: shutting down entire businesses, hospital systems, banks, and critical
infrastructure” (2017). Cyber criminals are demonstrating their ability to access sensitive
information, disturb the integrity of personal data, and block the availability of information systems.
3
However, their ability to manifest the physical destruction traditionally associated with kinetic
warfare has yet to be fully realized. Dually noted by the GAO and U.S. adversaries, the nation’s
CIs and Key Resources remain vulnerable to the potential devastation of cyber-attacks. As
indicated in the Presidential Policy Directive 21 (PPD 21), U.S. CIs remain a high value target
[GAO-18-62, 2017]. According to these recent reports (EO, PPD, and GAO), implementations of
existing standards, policy, legislation, methodology, and tools have not provided sufficient
confidence, guidance, or rigor toward the effective protection against these increasingly frequent
and potentially destructive attacks [GAO-13-462T, 2013; GAO-17-518T, 2017].
As noted by these reports and the adversary’s ability to continually penetrate CIs, it is
critical not only to have the ability to assess the effectiveness of various security measures, but
also to have a method that cogitates (considers/includes) the complexity and interdependencies of
CIs. This research offers a case study to demonstrate such a method - the Bayesian Approach to
Security Effectiveness with metrics, modeling, and decision-support (BASE m2d) conceptual
framework. This comprehensive method is used to assess a CI’s security posture by evaluating
the effectiveness of not only implemented measures but proposed measures, as well; potentially
avoiding devastating (unintended or intended) consequences. As a result, the risk of not protecting
CIs or providing the resiliency required to maintain services to dependent key resources such as
hospitals is explored.
Specifically, this study examines the likelihood of impact to a patient’s health given a
successful cyber or physical (natural or man-made) Denial of Service (DoS) attack on a dependent
CI using the BASE m2d framework (construct).
4
Understanding the potential impacts to elements of the Healthcare and Public Heath (HPH)
sector given a successful Denial of Service (DoS) to CIs is imperative to ensure proper security
effectiveness measures are in place to avoid potentially irreversible consequences. Further, a
strategic, holistic construct is proposed to properly focus budget constrained resources based on
the assessment of potential weaknesses of CIs as defined per their security goals or protection
targets (patients, personnel, medical devices, etc.).
The objective of this study is to provide emergency management personnel a conceptual
framework and methodology to evaluate security effectiveness and effects of cascading risk that
may result from inadequate security measures. This research is presented as a proof of concept
using a combination of real and notional data. Elicitation of specific data from medical experts was
limited due to the acknowledged vulnerability of hospitals and the potential insight it may provide to
adversaries. This research revealed the troubling finding that of the 13 hospitals pursued for expert
elicitation, medical professionals from 10 distinct hospitals noted their current risk assessment
plans did not include CI interdependency patient impact metrics or analysis given a denial of
service on a dependent CI. Consequently, the disparate measures hospital engineers, IT
professionals, and physicians use today to protect and maintain services they provide for the
ultimate purpose of preserving life are discussed. Further, this framework is being offered as a
method that considers those distinct security measures and provides a holistic approach to ensure
better protection and resiliency toward patient care. The BASE m2d framework was validated with
data provided by medical professionals from 10 different hospitals.
5
1.1 RESEARCH BACKGROUND
1.1.1 OVERVIEW OF CI
As a result of devastating events (Oklahoma bombing, Katrina, 9-11, Stuxnet, etc.) and the nation’s
lack of preparedness, congressional attention has resulted in the government, academia, and
private industry taking action. The dedicated focus on Critical Infrastructure Protection (CIP) spans
across four presidential administrations. In 1996, President Clinton established the President’s
Commission on Critical Infrastructure Protection (PCCIP) (E.O. 13010). Although no immediate
threats to critical infrastructures were noted upon the release of the PCCIP in 1997, it did stress the
importance of CI interdependencies. In 1998 the Presidential Decision Directive, number 63 (PDD-
63) was released. This directive sought to protect, by the year 2003, the nation’s CIs from
deliberate attacks. PDD-63 was later updated by President Bush through the Homeland Security
Presidential Directive HSPD-7 to establish a national policy for Federal departments and agencies
to identify and prioritize United States Critical Infrastructure and Key Resources and to protect
them from terrorist attacks (HSPD-7, 2003). The E.O. 13130 established by President Clinton in
1999 and E.O. 13231 by President Bush in 2001, essentially instituted Information Sharing and
Analysis Centers (mostly facilitated by the private-sector) and a National Infrastructure Advisory
Council (NIAC). In 2002, the Department of Homeland Security (DHS) was established and
charged with the primary responsibilities of protecting the United States and its territories from -
and responding to - terrorist attacks, man-made accidents, and natural disasters (DHS.gov). In
2013, President Obama issued E.O. 13636 and PPD-21. These two directives aim to “enhance the
security and resilience of the nation’s critical infrastructure and to maintain a cyber environment
that encourages efficiency, innovation, and economic prosperity while promoting safety, security,
business confidentiality, privacy, and civil liberties.” (E.O. 13636, PPD-21) Most recently (2017),
6
President Trump released an Executive Order on Strengthening the Cybersecurity of Federal
Networks and Critical Infrastructure. Together, these policies are intended to achieve the following
(DHS.gov):
• Encourage the adoption of effective measures across all critical infrastructure sectors to
improve security and resiliency and reduce risk from cyber-attacks to essential functions
and services by publishing a Cybersecurity Framework (the Framework, 2017) that will
provide owners and operators with a prioritized, flexible, repeatable, performance-based,
and cost-effective set of validated security controls based upon industry best practices.
• Enhance timely, relevant, and accurate information sharing on significant risks by
implementing a program to develop and rapidly share unclassified information with
critical infrastructure owners and operators, enabling the adoption of effective mitigations
to prevent or to reduce the consequences of significant incidents.
• Align responsibilities of public and private partners to efficiently allocate risk reduction
responsibilities by conducting an analysis of the existing critical infrastructure public-
private partnership model and recommending options for improving the effectiveness of
the partnership in managing both the physical and cyber risks.
• Promote innovation in novel risk-reduction solutions by developing a National Critical
Infrastructure Security and Resilience Research and Development (R&D) Plan to identify
priorities and guide R&D requirements and investments toward those solutions that will
help assure the provision of essential functions and services over time.
• Ensure that privacy, civil rights, and civil liberties are protected as a foundational part of
all risk management efforts by conducting an assessment of the privacy, civil rights, and
7
civil liberties implications of all EO 13636 and PPD-21 programs and recommending
revisions to proposed initiatives as required.
The Presidential Directive 21 (PPD 21) identified 16 CI sectors and designated specific federal-
agencies to facilitate/head protection and resiliency programs and activities. The sectors are
identified as follows:
1. Agriculture and Food 2. Banking and Finance 3. Chemical 4. Commercial Facilities 5. Communications 6. Critical Manufacturing 7. Dams 8. Defense Industrial Base 9. Emergency Services 10. Energy 11. Government Facilities 12. Healthcare and Public Health 13. Information Technology 14. Nuclear Reactors 15. Transportation Systems 16. Water and Sewage
It is commonly acknowledged that the interdependencies between critical infrastructure sectors
are of great importance to the protection of the nation.
1.1.2 HEALTHCARE AND PUBLIC HEALTH
Healthcare and public health facilities rely on various CIs in order to maintain daily operations. A
cyber or physical attack on any of those interdependent CIs can indirectly have a detrimental
impact on a patient’s health or their personal data. Depending on the motivation of the attacker,
i.e., to disturb the confidentiality, availability, or integrity of the hospital service or patient’s data, the
8
impact can be irreversible. Table 1 describes the critical dependencies between various sectors to
HPH. For examples, hospitals rely on critical services such as reliable power, clean water supply,
and available communications. An illustration of CI interdependency includes the following: Water
and Communication CIs depend on Energy (power) CIs, while Emergency Service (i.e.,
ambulances) CIs rely on Communication CIs. A DoS of critical services to a hospital from either a
cyber or physical attack can have a cascading effect if the proper protection and resiliency security
measures are not implemented.
Table 1. Healthcare and Public Health Sector CI Dependency (DHS.gov)
Understanding how and where to properly address and allocate security measures in a
budget-constrained environment will prove invaluable to ensure these critical resources/services
are uninterrupted (or have minimal or acceptable impact). A case is modeled in this research
where a patient in ICU is critically ill and depends on dialysis for survival. Given a DoS on a Water
CI, the hospital could be subsequently impacted if the proper back-up resources are not engaged
or available in a timely manner. The calculated System Security Effectiveness Index (SSEI)
defined in this study uses Systems Engineering/Systems Thinking concepts as a foundation to
9
inform the decision-maker of deficiencies internal and/or external to the infrastructure, enabling a
holistic, proactive assessment of their security effectiveness (of current or proposed security
measures) before an actual attack occurs.
A CI failure can be due to a successful attack, whether virtual or physical, that results in a
service interruption (partial shutdown or complete shutdown), ultimately having a 2nd, 3rd or 4th
order effect [Figure 1].
Figure 1. CI Interdependency Multi-order Effects
The National Association of County and City Health Officials (NACCHO), in summary, have
identified four categories of cyber-attack impact on healthcare and public health facilities
(NACCHO 2014):
1. Loss of integrity: Patients and practitioners may lose confidence in a healthcare
provider’s ability to maintain patient privacy due to perceptions of inadequate security.
2. Loss of availability: Cyber threats to data and operational systems can: take a facility off-
line, leading to disruption of care; create loss of access to health records, limiting the
10
provider’s ability to provide appropriate care, shelter, and medicine; disrupt emergency
telephone lines and EMS systems; and slow or disable emergency medical response
systems. Cyber-attacks can also prevent or impact production and manufacturing
of medical equipment or drugs.
3. Loss of confidentiality: The exposure of personal data can trigger ripple effects for
victims of cyber-crime, including theft or loss of a patient’s private information or discovery
of patient information on personal medical devices.
4. Physical destruction of systems: Cyber-attacks could damage physical systems used to
perform functions, such as regulate utilities critical to healthcare and public health and
could shut down or slow supply chains, impair patient care, and impede emergency
response, potentially leading to significant loss of life.
Public trust depends upon the sustainability, resilience, integrity, and availability of national HPH
critical infrastructure [NACCHO 2014]. Research results from this study reveal that hospital
engineers have performed due diligence to ensure if power is disrupted or water supplies have
been tainted or halted, backup generators and alternate water supplies are available to maintain
critical services. However, this research further revealed that most hospitals have not performed
additional risk assessments to understand or evaluate the potential impact of a DoS (i.e., water,
power) to the patient.
1.2 MOTIVATION
This study is motivated by the need to do more to protect and maintain the nation’s CIs and the
services they provide. In light of the mere possibility that physical destruction or loss of human life
11
can result (directly and/or indirectly) from a successful attack on a CI, is cause enough to pause
and re-assess the effectiveness of security measures in place to protect and provide resiliency.
1.3 RESEARCH PROBLEM
The indirect consequence of a DoS on a CI can be devastating to those that depend on its
services. The need to do more to protect and maintain the nation’s CIs and the services they
provide is paramount considering the dire consequences if neglected. Residential communities,
hospitals, banking, and government services are examples of resources that require sustained and
reliable provisions from CIs such as Energy, Water, and Communications for mere survival. Thus,
the ability to protect and/or maintain these critical services to dependent resources is crucial. As
CIs strive to institute protective and resiliency measures, the ability to assess the effectiveness of
those measures becomes more important not only to the CI, but also to the dependent resources.
This research explores the growing concern and significance of understanding potential
impacts of indirect consequences to dependent resources given a Denial of Service (DoS) to CIs.
To address the persistent challenge of protecting CIs and maintaining the essential services they
deliver, this research reveals that a methodology is needed to provide CI owners/stakeholders a
tool to evaluate their security posture while ultimately allowing for proactive provisioning before
potential disaster.
Current methodologies used to address the complex problem of improving cyber/physical
security protection of the enterprise, or specifically in this case, the nation’s CIs, must expand
beyond existing traditional approaches. Most security methods used today are considered from a
single-dimension. This is normally accomplished by protecting virtual or physical access to
architectural elements or components (network of routers, switches, servers, SCADA) from cyber-
attacks, e.g., by configuring firewalls, implementing policies, limiting access to data servers, and
12
training users. Although these techniques demonstrate a noble effort, they have proved to be
neither sufficient nor effective. Further, organizations, CI owners, and operators must have a
method to assess the effectiveness of the security program they put in place. A serious gap exists
in the tools available to assess the effectiveness of security measures which are designed to
mitigate disruptions to essential CI services (NIST 2014, GAO-16-152, GAO-17-518T 2017). Also
lacking are strategic methods to evaluate the subsequent impacts resulting from interruptions to
those services. Furthermore, a framework that empowers emergency management personnel to
reduce negative impacts of a CI DoS by strategically improving implemented security measures
does not readily exist today (NACCHO 2017). Existing literature describe numerous approaches to
CI interdependency analyses [Zio, Ouyang, Eusgeld, Haimes, DiMase, Borum, Kozik, Sikula,
Rinaldi, DiGiorgio]. However, there is limited research on estimating the likelihood of negative
impacts from those interdependencies or understanding the effectiveness of security measures
designed for their protection. This research fills a gap by providing a framework that allows
emergency management personnel to estimate the likelihood of impacts using a construct that
dynamically (through scenario analysis) and proactively addresses and evaluates the relative
effectiveness of implemented and/or proposed security measures designed to help minimize or
negate undesirable effects of CI service disruptions. We expand on knowledge, experience, and
recommendations offered by previously documented research of noted scholars.
1.4 RESEARCH OBJECTIVES
The objective of this research is to develop a solution to address the stated research problem.
Thus, a conceptual model that comprises a systematic, comprehensive (quantitative/quantitative),
scenario-based tool to proactively assess the effectiveness of implemented or proposed security
measures is offered. Specifically, the objectives are outlined as follows:
13
1) develop a strategic methodology to assess the effectiveness of security implementations
and aid in decision-making with a goal of proactively preparing for the inevitable occurrence of a CI
service interruption/disruption.
2) model how successful penetrations of CI vulnerabilities can have life-threatening
implications as an indirect or direct result of CI service disruptions;
3) identify exemplar metrics that could effectively be used to warn, prevent, or absorb CI
service interruptions.
Research Questions and Hypotheses
The following research questions are related to the problem statement and noted hypotheses.
Question #1: How can the assessment of security effectiveness of CI interdependencies and
vulnerabilities be modeled proactively (before occurrence or penetration) for improved
decision-making?
Question #2: How can combining probabilistic reasoning and a holistic, systems-thinking
based framework facilitate the assessment of relative effectiveness of CI and dependent
resources security measures?
Question #3: What metrics are used by hospitals to trigger auxiliary systems in the event of a
shutdown (partial or complete)? What metrics, if any are used to warn, prevent, or absorb CI
service interruptions?
Hypothesis 1a: Probabilistic reasoning and a systems-thinking based framework can be combined to assist in the overall evaluation (strength or weakness) of CI and/or dependent resources security effectiveness. Hypothesis 1b: Probabilistic reasoning and a systems-thinking based framework can be combined to quantifiably evaluate security effectiveness of Protection and Resiliency (P/R) for CIs and their dependent elements.
1.5 SCOPE AND LIMITATIONS
This research forms the basis and foundation for future research. The value of this research will
obtain its greatest return with the continuance of this research through studies in multi-order
14
dependency analysis of CI impacts towards the goal of improved security (protection and
resilience) effectiveness.
The bounds/limitations identified for this research include the examination of CIs as a black
box. It is important to note that the same CI/DR-HHM analysis can be performed looking internal to
the CI to assess the sub-components and the effects of any CI external influence it may cause.
While excluding a detailed assessment of each CI, it is asserted that the illustration and
demonstration of the methodology and conceptual framework is not lost.
Ten medical professionals (nurse, physician, or administrator) from ten different hospitals
provided expert knowledge based on the questions asked. Their responses are limited to their
individual experience and training. Conversely, those respondents that participated in this
research consisted of seasoned medical professionals appointed to speak on behalf of their
hospital’s practices.
1.6 RESEARCH CONTRIBUTION
This research seeks to contribute to the body of knowledge within multiple disciplines, as follows:
• Systems Engineering – provides a systematic, holistic, qualitative, and quantitative
approach to CI protection that considers the elements of the greater system, the element
interactions, and their emergent properties.
• Engineering Management – supports and informs decision-making using “what-if”
scenario analyses within the model to allow for proactive planning and better allocation of
resources based on security goals and implemented security measures.
• Systems Security Engineering/Information Security – combines security and systems
engineering best practices; this construct enables a comprehensive perspective of the
15
system and its interfaces/interdependencies to encourage better security in the appropriate
areas based on identified security goals.
• CI Protection/Resiliency – combines a framework for security professionals and decision-
makers to perform scenario-based, quantitative, and qualitative analysis of CIs and
dependent resources.
Specifically, the novelty expressed in this research expands upon existing CI interdependency
studies and analysis, while exploring a unique implementation of HHM and BBN through the
proposition of a hybrid multi-dimensional framework that generates quantitative and qualitative
results to assess security effectiveness.
1.7 SIGNIFICANCE/IMPLICATIONS OF RESEARCH
The ability to quantify the potential impacts to a critical hospital patient using numeric and
qualitative data can be instrumental for decision-makers seeking to preemptively execute
necessary security measures in order to demonstrate emergency preparedness, given a CI service
disruption. This conceptual framework allows CI owner/operators the capability to proactively
assess their situational awareness or security posture through scenario analysis, strategically
based on the organization’s security goals. For hospitals, maintaining public health by providing
continuity of services and ultimately preserving human life is of the highest priority; this is followed
closely by the goal of maintaining the confidentiality and integrity of patient records and billing
information. This methodology provides CI owners and dependent resources with a tool to assess
the exogenous (external) and endogenous (internal) nth order dependencies and impacts to ensure
emergency preparedness through various scenarios or what-if analysis [i.e. assess how the
degradation in power and/or water services may impact the ability of a hospital to provide
16
necessary services to a patient to sustain life]. The approach also allows for an analysis of
impact(s) between the CIs [i.e. how degradation in power may impact water resources and/or
communications]. The source of these impacts can easily go undetermined without multi-order
interdependency risk analyses.
Although this methodology and framework is demonstrated using a specific threat (Denial of
Service) to assess a specific purpose (impact to public health) given various possible vulnerabilities
(people, processes, tools, networks, or physical assets), the applications of this approach extend
beyond what is demonstrated here. This study approach could aid decision-makers assessing
various threats including the following:
• Availability of critical services to hospitals and patients;
• Integrity of the services provided by medical staff and vendors (medical devices);
• Confidentiality of patient records, billing, and pharmacy data.
Furthermore, this research suggests that in order for a complex, interdependent system of CIs to
effectively provide critical services to dependent resources, more effective and efficient standards
need to be implemented. Standards that mandate CIs communicate (share information) across
CIs and to those that depend on their services, in accordance with a security effectiveness
taxonomy understood by the impacted community of stakeholders. The SSEI concept and
construct offered in this research would allow CIs to communicate in a common language at a
confidential or sensitive information level, if necessary. This would allow appropriate security
measures to be considered from the perspective of their own internal security effectiveness
evaluation, as well as the external interdependent sources security effectiveness levels/evaluation.
As an example, during the stakeholder risk assessment, knowing the SSEI of other CIs as well as
your own SSEI, would aid decision-makers in a more efficient allocation of resources to effectively
17
maintain their security goal/target at an acceptable level of protection with the appropriate
resiliency, given a successful penetration or attack. Further, if a CI that is providing critical services
has a SSEI of 0.65, a dependent resource may want to ensure that his/her internal/individual SSEI
compensates for the weakness of that CI, potentially with a more immediate failover system for
power, or maintain a larger back-up water source or more robust filtration system.
1.8 DEFINITIONS OF KEY CONCEPTS
The proposed construct provides guidance on evaluating the security effectiveness of the
protective or resilient resources a CI operator/owner has chosen to implement - in a systematic,
quantitative, and performance metric-based approach. The following paragraphs describe the
essential elements of the combined framework and their relevance.
1.8.1 SECURITY EFFECTIVENESS FOR THE OPERATIONAL ENVIRONMENT
Relative effectiveness is best defined in its operational environment. In this study, the operational
environment is bounded by the components’ internal and external (interfaces) to the CIs and
dependent resources in question. The following definitions are important to note:
Security - the extent to which security measures provide protections that detect, deter, neutralize, and mitigate potential threats, while also providing resiliency measures to resist, respond, recover, absorb, and adapt to availing threats. (DHS NIPP, 2013)
Security Effectiveness - the degree to which security implementations provide adequate protective and resilient measures, allowing business operations to be maintained at an agreed upon level of service per the enterprise security goal.
Risk Management Effectiveness – determined by “whether and how much risk was actually reduced or whether risk was acceptable…” (Hubbard, 2009)
18
Security effectiveness, as defined above, implies that implemented security measures should not
impede, interrupt, or disturb critical operations of the enterprise, unless by design in order to
protect systems or persons from active attack.
Effective protection for one organization or CI may not apply to another organization or CI.
Measures applied for a specific threat may not be as effective for a different threat. The same
paradigm applies when measuring in different operational environments and for different security
goals. A more targeted solution considers what is relative or relational to the problem and specific
influences to the overall system. As a result, this research addresses security effectiveness more
appropriately as relative security effectiveness. Specifically, this research asserts relative security
effectiveness is best achieved by first defining the operational environment, understanding
associated dependencies, identifying the goal or target to be protected, and evaluating the problem
with a specific threat in mind.
1.8.2 HIERARCHICAL HOLOGRAPHIC MODELING (HHM)
HHM is one approach to multi-dimensional modeling (modeling from various/multiple perspectives).
The philosophy of HHM is grounded in the fundamental principle that complex, large-scale systems
such as CIs cannot be sufficiently appreciated or modeled in a planar or singular context. Haimes
[1981] states:
“The HHM approach (philosophy) recognizes that no single vision or perspective of a system is
adequate to represent a system and its component parts. Instead, the HHM approach identifies
and coordinates multiple, complementary decompositions of a complex system.”
HHM was chosen for this study to incorporate societal, legislative, environmental, spatial, and other
relevant dimensional perspectives that may contribute to the strength or weakness of security
posture. A CI/DR-HMM, developed for this research, is defined here as the HHM generated
19
specifically for the purposes of evaluating CIs or dependent resources. The HHM categories and
variables were extracted from a multitude of sources, to include the Department of Homeland
Security NIPP.
The HHM philosophy provides comprehensive, multi-dimensional insight into an otherwise
hidden problem/solution space to measure security effectiveness. To demonstrate the concept,
weights are distributed equally among the five (5) categories of the HHM (threats, vulnerabilities,
protection, resiliency, interdependencies), resulting in a sum of 20 percent for each hierarchical
category – totaling 100 percent for the entire critical infrastructure. Additionally, each category is
an aggregate of its components (i.e., protection includes detect, deter, neutralize and reduce.) See
Figure 2.
Figure 2. HHM for Critical Infrastructure or Dependent Resources (CI/DR-HHM)
20
This risk-assessment consists of input gathered from multiple stakeholders, such as engineering,
IT, and medical professionals. Each CI owner or decision-maker calculates their CI-HHM score as
described in subsequent sections. This information is used in the evaluation of the overall SSEI.
1.8.3 BAYESIAN BELIEF NETWORK (BBN)
BBNs are graphical illustrations of probabilistic dependencies (links) between variables (nodes).
The graph is a Directed Acyclic Graph (DAG) and the dependencies are such that any node given
its parents in the graph is independent of its non-descendants (Pearl, 1988). Like BBNs, attack
graphs are visual representations of physical and/or logical access into and within an enterprise,
network or CI.
An attack graph, as discussed in Frigault’s work [2014], can be represented as a DAG, coupled
with conditional probability tables (CPT) to constitute the BBN. A thorough implementation of
attack paths considers all paths that an attacker may exploit, both virtually and physically, to
access the CI/enterprise, network, or system. To demonstrate the BASE m2d concept the network
was modeled at the highest CI nodal hierarchy (black box) and the attack paths are notionally
identified via the DAG.
BBNs employ the fundamental premise of the Bayes Theorem:
21
The stated probability of an event or hypothesis is conditional based on the available/known
evidence in the relevant context. This condition can be made explicit by the notation P(H|E), which
reads as "the probability of event H given the evidence E." BBN is a method for understanding
evidence in the context of previous knowledge or experience [Pearl 1988]. The utility of BBNs has
become increasingly popular over the past decade in various fields of study to demonstrate
reliability, predictions, diagnosis, and decision analysis, among other uses. If it is accepted that
prior knowledge has intrinsic value, there is basis for using BBN.
In this study, a BBN is generated illustrating the dependencies and potential impacts of
successful penetrations originating from CIs. The BBN is used here for its ability to account for
uncertainty and limited available data of CI probability of attacks and interdependency/impact data.
For this study, the proof of concept is demonstrated by using historical and relative notional data
(prior probabilities), while the unknown values are calculated through a Bayesian software
simulation tool (Netica v5.15) to infer the CI interdependency impacts to dependent resources.
1.8.4 SYSTEMS SECURITY EFFECTIVENESS INDEX (SSEI)
The SSEI is a calculated value, resulting from risk-assessment performed by stakeholders to
understand (quantify) the relative security effectiveness and posture of CIs and/or dependent
resources. This index is designed to allow owners/operators the ability to assess and
communicate the strength and weakness of implemented and/or proposed security measures. The
SSEI serves as an evaluation of the risk mitigation steps a CI or dependent resource has taken to
protect against service disruptions. The BASE m2d framework is the vehicle developed to apply the
index. We show how an organization can use their self-evaluation of security effectiveness to
estimate the multi-order impact(s) of a CI service disruption.
22
This research is intended to demonstrate how the SSEI (index) can be determined and used to
understand and improve security effectiveness. It ranges from 0 to 1 (0 – 100%), with a low index
indicating a weak or poor security effectiveness rating. Section 4.2.5 describes how the SSEI was
constructed to demonstrate the concept of this research. The BASE m2d conceptual framework is
the vehicle developed to exercise the index. The SSEI serves as an evaluation of the risk
mitigation steps a CI has taken to protect against DoS attacks or whatever threat is being
assessed. For example, based on the measures taken in various areas of security, per the CI/DR
HHM categories, a CI or DR would self-assess their overall security effectiveness (SSEI) to
determine their current posture or where they could improve. The BASE m2d framework is
provided for the CI owner to assess various scenarios given their current or objective SSEI.
Alternatively, an objective or threshold (minimum) SSEI can be obtained from a trade analysis to
determine the index required so as not to negatively impact the security goal (or have an impact of
an acceptable level). A general scale was developed for this study and used to illustrate the SSEI
concept.
1.9 ORGANIZATION AND OUTLINE
This document consists of nine sections: Introduction; Literature Review; Research Methodology;
Hospital Case Study; Data Analysis and Results; Conclusions; Recommendations for Future Work;
References; and Appendices. The Introduction details the research background, motivation,
hypotheses/questions, and the significance of the study. The Literature Review examines relevant
studies on critical infrastructure protection and resiliency, implementation of BBNs and HHMs for CI
analyses, and security effectiveness approaches. The Research Methodology describes the use of
survey research for studying existing CI interdependent patient-impact risk assessments performed
at hospitals, data collections, and sources and methods. The Hospital Case Study applies the
23
proposed methodology and implementation of the BASE m2d construct. The Data Analysis and
Results describe the statistical analysis of the data and results of the hypotheses testing. The
Conclusion section details the findings of this study from the perspective of the research questions
and hypotheses. The Recommendations for Future Work describes potential research directions
suggested to further this study. The References section contain a bibliography of the resources
used throughout this research. Finally, the Appendices provide supplemental material as a result of
this research.
24
CHAPTER 2 - LITERATURE REVIEW
The purpose of this chapter is to review, assess, synthesize, and critique existing literature with a
goal of furthering the body of knowledge in the field of evaluating and improving CIP/R security
effectiveness. To address the stated research problem in accordance with the established research
goals, existing tools (models, techniques, and approaches) developed for the purpose of
performing risk analysis of CI interdependencies were reviewed and compared against criteria
collected from current literature. This chapter evaluates how current approaches assess CIP/R
security effectiveness, given the complex, interdependent nature of CIs. Ultimately, models were
reviewed for their ability to assess multi-order (hidden) effects inherent in CI interdependencies
combined with the capability to insert mitigation, scenario-based modeling to potentially reduce
vulnerabilities. While compiling this literature review, it was necessary not only to express the gaps
noted in existing literature but to clearly articulate the distinctions of my research objectives, while
specifically stating how this study expands upon existing research. The hierarchical models chosen
for hybridization are stated up front, while justification for that selection is supported in subsequent
sections that detail the review of related works.
2.1 REVIEW OF RELATED WORKS
Review of literature from noted scholars (Ayyub, DiMase, Borum, Ryan, Di Giorgio, Pettigrew,
Bayuk, Haimes, Satumtira, Ghorbani, Rinaldi) identified relevant attributes/criteria to effectively
achieve the goal of generating a comprehensive framework, given complex adaptive systems, such
as CIs:
25
1. Align/trace to security goals
2. Strategic/systems engineering approach
3. Performance based metrics
4. Quantitative and qualitative assessment
5. Scenario or what-if analysis for decision making
6. Accommodates uncertainty
7. Allows for limited data
8. Assess security effectiveness of security measures
9. Extensible application
10. Assess indirect consequences/Interdependency analysis
Although these scholars have acknowledged the criteria above as imperative components to
model/provide/improve effective security - current models, methods, and techniques at most only
incorporate two or three components. Thus, the ability to assess the effectiveness of security
implementations on a holistic level has been limited.
2.2 OVERVIEW OF CIP/R ANALYSIS
Government agencies, private sectors and noted scholars have done a thorough job identifying the
importance of CIP (GAO, 2008-20014; PPD21; Zimmerman, 2001; Rinaldi, 2001, 2004; Moteff,
2005; Huang et.al.) Al., 2014; Cummings, 2014; Ezell, 2005; George, n.d.; Richard, 2008). Others
have gone further to note various ways to incorporate risk management in CIP analysis (Bensi,
2013; Haimes, 1995, Chittister, 2012; Kjølle, 2012). Some have emphasized that without
considering the interdependence of CIs, an analysis would be inadequate (Gheorghe 2005;
Haimes, 2004; Zimmerman, 2001; Santos, 2006; Zhang, 2011; Zio, 2013). Also noted is the fact
that more quantitative methods should be developed, implemented, and accompanied by
26
qualitative analysis (Kjølle, 2012; Ryan, 2005; Di Giorgio, 2012). It has been predominantly
discussed by those in academia and the government that modeling and simulation techniques are
effective in doing predictive, scenario-based analysis of CIP (Ouyang, 2014; P. Pederson, 2006; Di
Giorgio, 2012). Additionally, there has been a recent surge in adding resilience techniques based
on the realization that techniques or tools will never fully protect CIs or dependent resources
(Ouyang, 2012, 2014; Kahan, 2009; Vugrin, 2010, Little, 2013; PPD21, 2013; NIPP, 2012; Biringer,
2010).
Each of the aforementioned scholars acknowledge that more needs to be done to protect and
maintain our nation’s CIs; however, review of these related works primarily revealed that prevailing
methodologies do not provide a systematic, comprehensive approach towards assessing and
acquiring security effectiveness for CI protection and resiliency. In light of the heightened focus on
CIP and evidence of repeated penetrations, standards, protocols, and procedures have been
developed - only to provide a false sense of security. This study expands on
knowledge/experience and recommendations offered by previously documented research.
The following graphic depicts areas of existing research; while the area in grey denotes the
gaps that, if filled would constitute a comprehensive solution. This research targets the noted
gaps.
27
Figure 3. Research Focus Areas
Review of literature revealed both qualitative and quantitative methods are most effective when
combined to aid in reducing the likelihood of the undesired consequences of a successful attack on
a CI (Adar, 2005). Thus, the concept of combining HHM and BBN were explored; two hierarchical
models, one allowing for a qualitative analysis (HHM), while the other provides for a quantitative
assessment (BBN). The fundamental philosophy of HHM and the probabilistic backbone of BBN
were combined, with the “tuning” mechanism of a Systems Security Effectiveness Index (SSEI), in
an effort to develop a more comprehensive approach to ultimately evaluate and improve the
effectiveness of security measures. The BASE m2d conceptual framework is offered as a
contribution to the CIP/R crusade.
28
In this chapter we discuss the comparative analysis performed to select models chosen for this
research. Additionally, existing literature employing applications of HHM and BBN for CIP/R, and
other methods, their uses, and individual limitations are reviewed.
This literature review is organized as follows: Approaches to CI protection and resiliency;
Approaches to Measuring Security Effectiveness for CIs; Implementations of HHM for CIP/R;
Implementations of BBN for CIP/R; Literature Review Summary.
2.3 APPROACHES TO CI PROTECTION & RESILIENCY (CIP/R)
Successful attacks on CIs resulting in physical destruction have raised growing concerns regarding
the effectiveness of various techniques implemented for the purpose of providing protection. This
research examined existing methods, techniques, and strategies used to evaluate the
effectiveness of security measures for Critical Infrastructure Protection and Resiliency (CIP/R).
Specifically, this study sought to understand if and how these methods considered or extended
measures to protect dependent (2nd/3rd order) resources in a manner that is systematic, proactive,
and holistic, such that it assists in effective, efficient, and informed decision-making.
As noted by many scholars researching CI protection, there does not exist today a silver bullet
approach that completely protects and prevents the interruption or denial of CI services (Biringer
et. al., 2013). Instead, a more strategic and effective approach is needed, to include having the
ability to provide resiliency to maintain service in accordance with security metrics and stakeholder
goals. Biringer explains that security systems must be designed relative to the specific security
concerns of the infrastructure, the threat to the infrastructure, the security concerns of the
infrastructure, and the protection goals of the security system. They further elaborate that each
owner of the site, facility, or system must specify or describe the protection goals of its security
system to allocate sufficient financial resources and labor to meet goals with a clear understanding
29
of the level of consequences that are acceptable if the protection goals cannot be met (Biringer et.
al., 2013). Similarly, this study asserts that within the design, the CI owner/operator must consider
how a realized vulnerability of the infrastructure may affect the services provided by the
infrastructure, ultimately impacting dependent resources.
Over thirty-five models, techniques, and approaches were reviewed, with data sourced from
Ouyang (2014), Eusgeld (2010), Idaho National Labs (Pederson, 2006) and Satumtira (2010), and
Vugrin (2010), to assess how each technique synergized the multi-dimensional, multi-objective,
qualitative, stochastic, and hierarchical nature of CIs and dependent resources (CI/DR). Although
each model was in various stages of maturity (R&D, Internal-only, operational), they were each
designed for the purpose of analyzing CI interdependencies. Many were designed for a specific CI
(internal dependencies), others intended to manage cross-sector dependencies. It was unclear
which tools were designed to evaluate multi-order effects (indirect consequences of negative
events), which is of great interest to this study. In the models reviewed, resiliency was handled, at
most from the perspective of redundancy. Many of the tools had the ability to perform sensitivity
analysis and the ability to determine various “strength” of dependencies (i.e. which dependency
had the greatest impact on another CI). Various decision analysis techniques were built in to
determine or indicate priority and relative importance; however, very few of the models illustrated
the ability to assess dimensional interdependencies (legislative, societal, economic, stakeholder,
etc.). At most, a few models had the ability to incorporate temporal, spatial, and geographic data.
Five models were highly regarded by the DHS: Athena, CARVER, Critical Infrastructure Modeling
system (CIMS), Knowledge Display and Aggregation System (KDAS), and Maritime Security Risk
Analysis Model (MSRAM). Each of the five models are considered Model-Based Risk Analysis
(MBRA) tools, known for their ability to aid in risk-informed decisions (Lewis, 2012). CARVER,
30
Athena, KDAS and MSRAM were each designed specifically for military and government entities,
while CIMS targeted emergency planners and responders as end users. Of all the models
evaluated, no tool clearly articulated how or if effectiveness was assessed; and the extent to which
resiliency was addressed, it was limited to identifying redundant components/measures. No tool
addressed resiliency as it is defined by the NIPP (Ouyang, 2013). The ability to handle minimal
data and account for uncertainty was only managed by tools with a stochastic engine, however,
even those tools did not address effectiveness from the perspective of both protection and
resiliency, nor from various dimensions, as previously described.
Table 2. Literature Review CI Model Comparative Analysis
Although unable to physically manipulate the models evaluated for this research, the data available
served well in filtering various capabilities and limitations of each tool. While each tool appeared to
serve a valuable fit for its purpose, it did not appear evident that they lent themselves to trivial
modification for extensibility to incorporate additional/lacking features. A tool is most valuable and
effective when designed from its core to allow for modular growth that enhances or provides
Criteria/Features
B A S E m
2 d
B o
lo g
n a
N IP
P
P C
C IP
P P
D 6
3
B r ie
r e
R in
a ld
i
P e
e r e
n b
o o
m
H a
im e
s
Z im
m e
r m
a n
M e
n d
o n
c a
O s o
r io
B e
n s i
H a
im e
s
A IM
S
A t h
e n
a
C A
R V
E R
C I3
C IM
S
C IP
/D S
S
C IP
M A
C IS
IA
D E
W
E M
C A
S
F A
IT
F IN
S IM
F o
r t
F u
tu r e
IE IS
S
II M
K D
A S
K M
V
M IN
M S
R A
M
M U
N IC
IP A
L
N - A
B L
E
N E
M O
N e
t- C
e n
tr ic
G IS
N E
X U
S F
u s io
n
F r a
m e
w o
r k T
M
N g
to o
ls
N S
R A
M
P F
N A
M
T R
A G
IS
T R
A N
S IM
W IS
E
Conceptual Modeling and/or Simulation ToolsApplied
1 Align/trace to security goals x x x x x x
2 Strategic approach x x x x x x x x x
3 Performance-based metrics x x x x
4 Quantitative and qualitative x x x
5 Scenario or what-if analysis x x x
6 Accommodates uncertainty x x x x x
7 Allows for limited data x
8 Assess security effectiveness x x x x
9 Extensible application x x x
10 Interdependency Analysis x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x
11 Protection x x x x x x x
12 Resiliency x x x x x x
Hybrid
31
additional capability, vice adding on to a tool that was not built to be dynamically modified.
Consequently, I sought to establish the BASEm2d conceptual framework, a tool that asserts to
provide what existing tools lack, a comprehensive approach to assess security effectiveness of
measures proposed/implemented for CI protection and resiliency; while also providing modularity
for future improvements and/or additional functionality.
2.3.1 IMPLEMENTATIONS OF DECISION ANALYSIS TOOLS FOR CIP/R
HHM has been used extensively in assessing and identifying sources of risk, complex
interdependencies of water resource CIs (Chittister e.t al. 2012; Haimes 1995), and Supervisory
Control and Data Acquisition (SCADA) networks (Haimes 2005). However, this research will be the
first implementation of HHM to assist in the identification of strength or weakness weights/index,
coupled with using BBN analysis to assess and improve security effectiveness of CI protections
and resiliency.
Haimes originally designed HHM to identify sources of risk. Although modified in this study
from its original design, I maintain and leverage the integrity of the HHM philosophy and concept
for its ability to not only identify sources of risk, but to assist in the identification of relevant
variables hierarchically, in various categories, and from multiple dimensions. Approaches such as
Analytical Hierarchy Process (AHP), Multi-Attribute Utility Theory (MAUT), or Multi-Criteria Decision
Analysis were evaluated as comparable models; and although each of these methods also assist in
decision making and allow for a structured way of framing the problem, the need to assign relevant
weights to each criteria to show importance was not necessary to meet the objectives of this
conceptual study. Instead, to demonstrate the preliminary concept, variables were elicited from
existing research previously collected from experts at the DHS and documented in the NIPP. CI
experts determined that the variables identified within the NIPP held equal weight at the highest
32
level of evaluation. In an effort to scope individual components of this framework I leverage
(extend) vetted research to focus this research on demonstrating the comprehensive framework.
This research acknowledges that criterion weights are a reality (all variables may not be equally
important), hence they may vary depending on budget constraints and available resources.
Variables should be re-evaluated/weighted on a case by case basis, which would suggest the use
of the aforementioned decision analysis models such as AHP and others. This is recommended as
a future enhancement to the BASE m2d preliminary framework. The HHM component of this tool is
a modular component which can be modified or replaced as the user desires.
2.3.2 IMPLEMENTATIONS OF PROBABILISTIC RISK MODELING FOR CIP/R
Graphical probabilistic models such as Markov Random Fields (Markov Networks) and Bayesian
Belief Networks were explored to address the uncertainty of complex system interdependencies
and the very real occurrence of limited data; specifically, a probabilistic model that allows for
scenario/what-if analysis, with a user-friendly interface, and one that does not require great
statistical knowledge. Markov Networks are known for their power and flexibility (undirected,
allowing cycles); BBNs are considered to be restricted by comparison (directed, acyclic). It was
discovered that both Markov Networks and BBNs would suffice for this study, however, BBN was
chosen simply based on its immediate capabilities, the researcher’s familiarity with the method,
and its ease of use.
A review of existing literature indicates BBNs have been implemented to model and analyze
the interdependencies of CI (Di Giorgio, 2011). BBNs have also been used to predict the likelihood
of terrorist attacks on CIs (Johan 2009; Haimes 2004). Kazak (2010) uses BBN with a security
ontology to assess the severity level of detected threats, while Faribault (2014) demonstrates the
utility of BBN to assess vulnerability in computer networks. Additionally, Queiroz (2013), et. al. use
33
BBN to evaluate information diversity within SCADA systems. There is also extensive research
available implementing BBNs to provide earthquake decision-support systems for seismic
infrastructure risk assessment, to include Bensi (2010), Bayraktarli (2005), and Kheun (2009). In
the medical field, BBNs are currently applied to assist in more accurate diagnoses (Forsberg
2011), to predict the occurrence of cancers (Burnside, n.d.), and to estimate patient survival given
the presence of certain cancer prognostic factors (Forsberg 2012).
Although it was determined through literature review that BBN is effective and most
appropriate to evaluate CI vulnerabilities and medical prognosis/diagnosis, gaps exist in its
implementation as a catalyst for stimulating decision analysis for the purpose of assessing and
quantifying security effectiveness toward improved CI protection and resiliency. Further, no
comprehensive approach that generates an effectiveness index based on existing implemented
security measures for the purpose of further improving security posture was found.
As previously discussed, various CI interdependency analyses/approaches have been
extensively explored by scholars such as Rinaldi, Haimes, Di Giorgio, Zhi-yan, Macaulay, and
others. However, this research extends upon that research with provisions for a holistic framework
to address relative security effectiveness, given CI interdependencies, to make informed decisions.
It is acknowledged that even the best efforts will not afford absolute protection, thus the
need to simultaneously prepare for resiliency (i.e., adaptability, recoverability, absorption, etc.) of a
cyber or physical attack. The BASE m2d framework is aimed at providing both proactive and
responsive measures toward better P/R. Subsequent sections of this paper detail the methodology
and the combined implementation of the associated models (HHM and BBN).
34
2.4 APPROACHES TO MEASURING SECURITY EFFECTIVENESS FOR CI
Methods used today to evaluate security effectiveness include variations on vulnerability analysis,
penetration testing, threat analysis, and/or risk analysis. It would be expected, at a minimum, for
organizations to perform some aspect of each of these activities before allocating resources to
improve their security effectiveness. Conversely, review of literature has revealed that those
employing any one of the aforementioned analyses, most often do not necessarily do so in a
systematic, holistic manner (Biringer, 2013; Pettigrew, 2009; Ryan, 2008.). For example, the
assessment of various threats/vulnerabilities from the perspective of various stakeholders
predicated on the organization’s security goals, using qualitative or quantitative performance-based
metrics to determine the effectiveness of the protection and/or resilience measures they have in
place. Additionally, until recently, those efforts that focused on vulnerabilities, penetration testing,
threats, and risk did so only as it related to protection. More recently, there has been an exertion
toward the realm of implementing practices to ensure resilience. Currently, the review of related
works primarily identifies that existing methodologies do not provide an approach toward assessing
and acquiring security effectiveness for CI protection and resiliency.
2.5 SUMMARY
In Chapter 2 the problem currently faced by the nation to protect and maintain CIs from successful
cyber or physical attacks was discussed. Several models were reviewed to evaluate their ability to
address the multi-dimensional, multi-objective, quantitative/qualitative, and hierarchical nature of
CIs and dependent resources. Of the models reviewed, no tool clearly articulated how or if
effectiveness was assessed; and the extent to which resiliency was addressed was limited to
identifying redundant components/measures. The ability to handle minimal data and account for
35
uncertainty was only managed by tools with a stochastic engine, however, even those tools did not
address effectiveness from the perspective of both protection and resiliency, nor from various
dimensions, as previously described. Consequently, this research implemented the integration
(hybrid) of two hierarchical techniques that encompass each of the ten (10) aforementioned
criteria. It was hypothesized that by combining multidimensional modeling such as HHM and BBN,
a conceptual framework could be developed to enable scenario-based analysis to assess the
effectiveness of implemented or proposed security measures.
Chapter 2 also discussed a detailed overview of existing techniques and models used today to
provide protection and resiliency to CIs and those that depend on its services. As previously
discussed, various CI interdependency analyses/approaches have been extensively explored by
scholars such as Bloomfield, Eusgeld, Haimes, Min, Ouyang, Kjolle, Liberati, Satumtira,
Zimmerman, Rinaldi, Haimes, Di Giorgio, Zhi-yan, Macaulay, and others. However, this research
extends upon that research with provisions for a methodology and framework to address relative
security effectiveness, given CI interdependencies, to make informed decisions.
CHAPTER 3 - RESEARCH METHODOLOGY
This chapter describes the research methodology chosen to investigate how two hierarchical
modeling techniques can be combined to provide a quantitative and qualitative conceptual
framework (BASE m2d) that can be used to assess and improve the relative security effectiveness
of CIs and dependent resources. Described herein, is the approach taken to develop, test, and
validate the holistic framework. The research method chosen consists of a survey designed to
elicit probability distributions from experts, which are subsequently employed to validate the BASE
36
m2d framework. To test the hypotheses, a hospital case study was designed to demonstrate the
frameworks’ utility, flexibility, and limitations.
3.1 RESEARCH DESIGN
This study utilized a focused cross-sectional survey to collect data from medical professionals
employed at 10 distinct hospitals. The survey was used to capture the knowledge and experience
of medical professionals regarding the use of metrics implemented by their respective hospital
facility to measure effectiveness and/or emergency preparedness. Data was also collected to
understand various impacts to a critically ill hospital patient (dependent resource) given a CI failure
or Denial of Service (DoS). Survey responses were collected via a web-based, electronic tool
(Survey Monkey). Using the expert elicitation method, the data was further used to validate the
BBN model and expected results. Elicitation of specific data from medical experts was limited due
to the acknowledged vulnerability of hospitals and potential insight it may provide to adversaries.
Thus, we use a combination of real and notional data and present this research as a proof of
concept.
A survey was used to evaluate various impacts to a hospital patient given a DoS to a CI and to
understand the knowledge of medical professionals regarding metrics implemented by their
employment facility (hospital). Surveys are often used to gather statistical data about
demographics, actions, techniques, perceived effectiveness, characteristics or attributes from a
selected or random community, or category of a specific population (Babbie, 2010; Creswell, 2009;
Salkind, 2009). Descriptive and inferential analysis was performed on the data collected using
Netica, SPSS, and Minitab.
The research survey process for this study maintained the strictest confidence of respondent
information and identities, as required by the GWU Institutional Review Board (IRB). No personally
37
identifiable information (PII) was acquired, and all metadata associated with each respondent was
securely discarded.
3.2 EXPERT ELICITATION
Expert elicitation (EE) is often used when it is not feasible to collect empirical data for statistical
analysis (Cooke 1991). According to Ryan, et. al., EE is designed to elicit, codify, and combine the
knowledge of people who have significant experience or expertise in a defined field in order to
assess unknown quantities or parameters (Ryan 2012). These scholars go on to state that the use
of “expert judgment is justified when quantitative data is missing, of dubious quality, or is
insufficient for obtaining reasonable statistical results.” Various methods are noted in scholarly
research of how to elicit, codify, and combine expert knowledge, as described by Cooke (1991).
For this research effort, methods detailed by Buede, Renooij (2001), and Pitchforth (2011) was
used based on its extensive application in Bayesian analysis. Bayesian Networks are often
created through the process of EE (Pitchforth 2012).
Studies have shown that experts tend to be overconfident about their judgments (Tversky
1974, Lin 2008, Flandoli 2011). Heuristics and biases are issues that often arise when eliciting
information from experts. To overcome these relevant concerns, scholars recommend a well-
structured elicitation process. According to Kahneman et. al., (1982) and Renooij (2001), bias is a
systematic tendency to take into account factors that are irrelevant to the task at hand, or to ignore
relevant facts, thereby failing to make an inference that any appropriate normative theory, for
example probability theory, would classify as necessary. There are two types of biases to
consider: motivational bias, which is caused by personal interest or circumstances experienced by
the expert; and cognitive bias which arise during the processing of expert information with the use
of heuristics (availability, anchoring, representativeness, and control) (Kahneman et. al., 1982).
38
Motivational bias can be mitigated by reassuring the respondents that their responses are for
information only and not a promise or commitment. Cognitive bias can be minimized by letting the
respondent know that they exist and by subjecting the experts to calibration (Hubbard, 2016). The
survey should consider these concerns in deciding upon the survey method used (Renooij 2001).
This research has taken specific steps to minimize bias, inconsistencies, potential errors, and
overconfidence. The following process was used to elicit relevant data from respondents:
Step 1: Expert Selection
Experts were selected by various representatives of each hospital solicited for data on this study
(Hospital Risk Assessment Office, Administrator of hospital, Chief Information Technology Officer,
etc.). Each respondent was selected based on their domain knowledge of hospital operations and
their ability to assess patient impacts. The respondents were advised that their individual
participation would remain anonymous and data provided would be voluntary, with no obligations
or retribution to their employment. They were also assured that the accuracy of their information
need only be based on their experience (Renooij 2001).
Step 2: Set Foundation for the Expert
During initial contact, the expert was advised of the purpose of the study, to include background
information, definitions, and scope. Expectations were detailed and the confidentiality of personal
information was emphasized. Special care was taken to ensure that the same contextual
information was provided to each participant in a common manner so as not to introduce bias in
judgment (Boring, 2005).
39
Step 3: Train the Expert
Participants were subjected to an electronic survey which included an introduction and described
the purpose of the study. The introduction described the basic process and flow of the survey, and
each section provided necessary instructions for completion. The goal of this activity was to
ensure the expert felt comfortable with the process and understood with clarity the objective of the
survey instrument. The multiple choice, five-point Likert scale questions eased the burden of the
respondents who may have not been comfortable with providing direct probability distributions.
Step 4: Elicitation of Judgments
Responses were collected via a web-based, electronic tool (Survey Monkey). Experts were asked
to provide minimal demographic information (i.e. years of experience, medical profession, and
experience in ICU or other emergency patient care). Expert responses were calibrated based on
absolute agreement in accordance with Intra-class Correlation Coefficient (ICC). Probability
distributions were indirectly elicited from each expert, capturing the likelihood CI service disruption
impacts to patients. The elicited data was used to validate the behavior of the BBN model.
Step 5: Aggregating the data for Consistency
Upon completion of the survey, verification consisted of checking whether the elicited probabilities
are coherent, obey the laws of probability, and are reliable (Fenton, 1998). According to Renooij,
an indication of the validity of the assessments can also be obtained by entering observations into
the belief network and computing the effect of the observations on the probabilities for certain
variables of interest. The outcomes for these variables can then be checked against available data
or presented to the expert (Renooij 2001).
40
3.3 SURVEY SCALE
The scale used for this survey instrument consisted of a five-point Likert scale. The questions
were rank ordered from lowest (very unlikely) to highest (very likely). As noted by Fowler, Hayes,
Nunnally, Punch, Weisberg, a graduated scale will maximize the degree of variability in the
responses and lend itself to an analysis of continuous variable data (Fowler, 1995; Hayes, 1998;
Nunnally, 1978; Punch, 2003; Weisberg, 1977). The chances of misclassifying the data due to
reverse coding will be significantly reduced with rank ordered responses (Punch, 2003; Weisberg,
1977). Each rank order corresponded/coded to a probability distribution as follows:
1 2 3 4 5
Very unlikely
Unlikely
Need More Info
Likely
Very Likely
(0-20%) (21-40%) (41-60%) (61-80%) (81-100%)
3.4 EXPERT ELICITATION CALIBRATION
Various methods exist on how to elicit, structure, combine, and calibrate an expert’s response to a
survey (Ryan 2012; Flandoli 2011; and Cooke 1991). Cooke’s Classical Method (1991) suggests
weighting expert’s opinions and experience with “seed questions,” to which the answers are
generally available and typically known by subject matter experts in the field to be studied. How
the experts respond are scored in accordance with the true answers and consequently weighted.
The weights are derived from a combination of the expert response to the seed questions and are
used to calibrate the “accuracy” of the experts’ opinion. Calibration measures the statistical
likelihood that a set of experimental results corresponds with the experts’ assessments (Cooke
2004). Alternatively, Hubbard (2016) discusses how he facilitates workshops to “calibrate the
expert” to improve one’s ability to subjectively assess odds. He teaches various methods to
41
reduce overconfidence and underconfidence in responses – known challenges to eliciting expert
judgment.
Expert responses used in this study were not calibrated as offered by Cooke, given no seed
questions were offered within the survey to calculate weights. To account for this, we attempted to
take extreme care during the expert training period, as preferred by Hubbard – calibrate the expert.
The probability distributions collected from experts were used to confirm BBN validation, i.e., does
the model behave as it should; are the simulated results as expected.
This overall elicitation approach was taken with caution and considered a sound way to
minimize biases and under/overconfidence. The following considerations were taken into account
to proceed with this method, when no other data exist (Johnson 2010):
• Detailed training of experts prior to the survey
• Clear, standardized instruction script
• Provided Likert scale with corresponding probability distributions
• Avoiding use of scenarios or anchoring data
• Allow for comments or feedback
3.5 SURVEY INSTRUMENT
This research leveraged the flexibility and convenience of a professional online tool (Survey
Monkey) used to collect data, extract, and compile the final results. Survey Monkey is a
convenient, web-based tool, available 24/7 to respondents during the data collection period.
Although many researchers find several advantages to using the online survey tool, such as being
cost efficient and providing quick results. Survey Monkey also allows for various design methods
to present/display questions and collect responses, it has a global (electronic) reach to extend
beyond places a researcher could physically be present, and it also tends to have a higher
42
response rate than other popular methods. Detailed benefits are described below:
Benefits of Electronic/Online Survey: http://writing.colostate.edu/guides/page.cfm?pageid=1406&guideid=68
• Cost-savings: It is less expensive to send questionnaires online than to pay for postage
or for interviewers.
• Ease of Editing/Analysis: It is easier to make changes to questionnaire and to copy and
sort data.
• Faster Transmission Time: Questionnaires can be delivered to recipients in seconds,
rather than in days as with traditional mail.
• Easy Use of Preletters: You may send invitations and receive responses in a very short
time and thus receive participation level estimates.
• Higher Response Rate: Research shows that response rates on private networks are
higher with electronic surveys than with paper surveys or interviews.
• More Candid Responses: Research shows that respondents may answer more honestly
with electronic surveys than with paper surveys or interviews.
• Potentially Quicker Response Time with Wider Magnitude of Coverage: Due to the
speed of online networks, participants can answer in minutes or hours, and coverage can
be global.
• Same strength as written survey
• Ability to consistently track responses
• Automatic randomization of questions and answers choices to remove potential biases
Drawbacks to Electronic/Online Survey:
• Sample Demographic Limitations: Population and sample limited to those with access to
computer and online network.
• Additional Orientation/Instructions: More instruction and orientation to the computer
online systems may be necessary for respondents to complete the questionnaire.
• Potential Technical Problems with Hardware and Software: Computers have a much
greater likelihood of "glitches" than oral or written forms of communication.
• Potential for SPAM
43
• Potential for survey fatigue
The survey questions were designed to be simple, straight forward, and elicit an intuitively positive
response (Punch, 2003; Weisberg, 1977). The questions were also designed to be without
negative statements, which have been known to confuse respondents and lead to non-normal,
diverged, and skewed distributions and result in weaker statistical correlations (Hayes, 1998).
3.6 VALIDITY OF SURVEY INSTRUMENT
Purpose: To collect relevant data for the purpose of understanding how hospitals assess,
measure, and/or utilize the following:
• Hospitals utilization/implementation of metrics to trigger alternate critical systems for
water, power, and communications
• Likelihood of Impact to hospital and/or critically ill patients, given a limited or complete
service disruption of power, water, or communications to the areas of cardiac care,
dialysis, and oxygen/ventilator – services to which the critically ill patient is dependent.
Approach: The results of the survey were used to validate the findings of the conceptual
framework. To determine if the results of the survey instrument are valid and reliable, the
respondent data was evaluated against the data produced by the tool. If an instrument is
unreliable, it is also invalid, because accurate findings cannot be obtained with inconsistent data
(Carmines, 1979). A valid survey instrument serves the purpose it is intended to serve and
provides correct information (Fink, 2003). This survey instrument was evaluated based on the
following criteria/tests:
44
RELIABILITY ▪ INTERNAL CONSISTENCY or Homogeneity using a Cronbach coefficient (α >0.7)
o Measures the extent to which a technique, experiment, or measuring procedure
assess the same characteristic or quality.
▪ INTER- AND INTRARATER RELIABILITY
o Measures the extent to which multiple respondents agree in their ratings of given
items.
VALIDITY
▪ CONTENT VALIDITY o Measures the extent to which the question/items thoroughly and appropriately
assess the characteristics or qualities it purports to measures.
▪ FACE VALIDITY
o Measures the appearance of the metric/question on the surface.
3.7 VALIDITY OF CONCEPTUAL FRAMEWORK
Purpose: The objective of the conceptual framework is to provide relevant information for the
purposes of providing proactive protection and resilience to CIs and dependent resources. In
doing so, the validity and reliability of the conceptual framework was evaluated. Specifically, the
following approach was used to measure the tools’ effectiveness for its purpose, and its ability to
perform as a hybrid model to measure and assess security effectiveness of CIs and dependent
resources.
Approach: Previous research performed by the DHS identified relevant variables used to
measure effectiveness for CI protection and resiliency. This research was furthered by using those
variables within the conceptual framework (BASE m2d) to demonstrate the ability to quantitatively
45
and qualitatively measure and assess security effectiveness of CIs and dependent resources.
Further, the data collected from medical professionals was used to validate the results of the hybrid
conceptual model.
3.8 DATA COLLECTION
Data was collected and provided from various sources as described herein. Ten medical
professionals from 10 distinct hospitals provided data through expert elicitation, to validate the BBN
model and expected results. DHS and various sources discovered through research provided the
relevant variables used for the SSEI and HHM. The specific CI categories and hierarchical
relationships used in this study were extracted from the Department of Homeland Security (DHS)
National Infrastructure Protection Plan (NIPP) and their associated Sector Specific Plans (SSP).
Historical and relational data was used as prior probabilities for the BBN analysis from sources
such as the medical professionals, DHS, Verizon 2013, 2014, and 2015 Breach Reports, Symantec
Annual Security Threat Report, and Verisign. Specific data for each CI was collected from
government sources such as DHS in collaboration with the Department of Energy (DOE), Water
Waste and Sewage (Environmental Protection Agency), and the Communications sector (National
Communications Systems). Previous research performed by the DHS identified relevant variables
for CI protection and resiliency (CIP/R). Patient impact data was collected per the Institutional
Review Board (IRB) guidelines, ensuring no personally identifiable information was acquired,
attributed, or misused. Survey Monkey, a web based renowned vendor often used in academic
research, was employed during this study as the survey instrument to facilitate the collection of
patient impact data from medical professionals. Results of the survey were used to validate the
BBN model and overall conceptual framework.
46
CHAPTER 4 – HOSPITAL CASE STUDY
4.1 CASE STUDY BACKGROUND
Public trust depends upon the sustainability, resilience, integrity, and availability of national
Healthcare and Public Health (HPH) critical infrastructure [NACCHO 2014]. Continuity of
healthcare and public health services are critical to response and recovery following a disaster or
emergency [NACCHO 2016]. Results from this research reveal that hospital engineers have
performed due diligence to ensure if power is disrupted or water supplies have been tainted or
halted, backup generators and alternate water supplies are available to maintain critical services.
However, this research further revealed that most hospitals have not performed additional risk
assessments to evaluate implemented security measures to allow them to understand, evaluate,
and reduce the potential impact of a CI DoS (e.g., water, power) to a patient or medical device.
Understanding how and where to properly address and allocate security measures in a
budget-constrained environment will prove invaluable to ensure these critical resources/services
are uninterrupted (or have minimal or acceptable impact). This case study models a critically ill
patient in ICU who depends on medical equipment (dialysis, defibrillator, etc.) for survival. Given a
DoS to a CI (power, water, etc.), the hospital could be subsequently impacted if the proper back-up
resources are not engaged or available in a timely manner
Multi-order, cascading effects are important to understand given they can occur as a result
of a direct or indirect attack or occurrence. A CI failure or DoS (resulting in a partial shutdown or
complete shutdown) can be due to a successful attack, whether virtual or physical, intentional or
unintentional, potentially having a 2nd, 3rd, or 4th order effect [Figure 2]. The case study modeled in
this study examines the 4th order effect to a patient that is depending on CI services to sustain life.
47
Figure 2. CI Interdependency Multi-Order Effects
4.2 CASE STUDY APPLICATION
The Bayesian Approach to Security Effectiveness with metrics, modeling and decision-support
(BASE m2d) framework uses a hospital case study to demonstrate the overall methodology.
Described herein are the steps to perform a risk-assessment using the CI/DR-HHM, calculate the
SSEI, and perform “what-if” analyses to determine the potential impact to a dependent resource
(hospital or patient) given a successful DoS to one or more CIs (water, power, communications).
Figure 4 represents the general flow of the BASE m2d framework.
48
Figure 4. General Flow of BASE m2d Framework
The following sections describe the ten-step methodology of the BASE m2d framework. The first
three steps define the problem-solution space; Steps 4-7 assess the current security posture using
metrics, the operational environment from multiple stakeholder perspectives using HHM, the
overall relative effectiveness using SSEI, and the likelihood of impact using BBN; while Steps 8-10
estimate the relative risk, and describe the iterative decision analysis process.
49
4.2.1 STEP 1 AND 2: DEFINE OPERATIONAL ENVIRONMENT AND SECURITY GOALS
The strategic implementation of this framework begins by establishing security goals within the
operational environment. The Department of Homeland Security National Infrastructure Protection
Plan (NIPP) has developed value propositions and/or security goals for each CI identified in the
plan. Establishing security goals includes documenting what is important to the organization and
considers perspectives of all stakeholders, to include CI owners/operators, dependent CI
owners/operators, vendors, consumers/customers, etc. Many decision-makers focus resources in
areas that have little to no impact on what they value, and without the full consideration of the
operational impact; thus, leading to security compliance with little security effectiveness. Once
goals are established within the operational environment, measures can be directly implemented to
monitor progress toward achieving those goals in accordance with the value proposition.
HPH Security Goal: For the HPH sector or hospitals, it is crucial that they maintain
(resilience) a certain level of business continuity to preserve human life and to protect
the confidentiality of information for their patients and personnel.
The HPH security goal identified above can be divided into two separate targets to protect: human
life and patient information. This case study focuses on preserving human life to demonstrate the
capabilities of the model; however, the model is extensible to include an analysis of the impact of a
successful attack on patients’ personal information, as well. That case is excluded here based on
the threat (DoS) in question, which is often employed for purposes other than to exploit personal
data.
50
4.2.2 STEP 3: IDENTIFY DEPENDENCIES
Internal and external dependencies (also known as potential attack paths) to the protection target
or security goal (hospital, patient), within the operational environment can indicate vulnerabilities.
Specifically, if there is a penetrable entry or exit point (link) to or from the target, strategic
consideration should be given to apply appropriate measures of protection or resiliency to prevent
undesired effects in the event of an attack or natural disaster. Links/dependencies may be
identified as having virtual and/or physical access and should be prioritized, especially in a budget
constrained environment. Identifying dependencies between CIs (water, power, communications)
and dependent resources (hospital, medical devices, patient) provides the topology to construct the
general Bayesian Belief Network.
THE METRICS
4.2.3 STEP 4: ASSESS/MEASURE THE SECURITY POSTURE
Relevant metrics should be identified and implemented to assess the current security posture of
the organization, particularly metrics that acknowledge and indicate internal/external degradation of
the infrastructure. Metrics chosen should pass the “so-what” test and should be selected in relation
to the security goal within its operational environment. They should be identified and defined
around the problem space. Without metrics, organizations will find it difficult to accurately gauge
effectiveness and articulate improvement. When metrics can be quantified as a number or
percentage, are contextually relevant, and measured consistently, they confer credibility to the
overall assessment (Jaquith, 2007). Jaquith goes on to state that good metrics should facilitate
discussion, insight, and analysis.
51
Security metrics are the servants of risk management, and risk management is about making
decisions. Therefore, the only security metrics we are interested in are those that support
decision making about risk for the purpose of managing that risk (Jaquith, 2007)
Getting the right metrics requires asking the right questions. Cyber-attacks may cause a temporary
disruption (minutes to hours), while natural disasters such as tornadoes or hurricanes may cause
long-term outages (weeks to months). A question such as “are failover settings for the backup
generator sufficient to not have a negative effect on the patient, in the event that power is disrupted
at the hospital’s main plant,” should lead to identifying the appropriate metrics that ensure the
ability to proactively monitor status and plan accordingly. Medical devices dependent on CI
services would benefit from metrics such as mean time between failure (MTBF) for monitoring or
alarm if a failover system (power, water) exceeds a certain value. Asking how long a backup
generator can support a critically ill patient surviving on a ventilator before asphyxiation or brain
damage occurs should also result in relevant metrics. Although the answer to this question may
depend on the severity of the patient’s illness, the reliability and sustainability of the medical
equipment should be measured, understood, and baselined accordingly, to assist in proper
planning.
Penetration testing should also be performed and results included in the overall
assessment to continuously monitor and capture anomalies due to unsolicited or unintentional
physical or cyber access. These combined techniques provide an understanding of the current
security posture and insight into the strength or weakness of the enterprise.
The BBN model developed for this research is structured such that if current measures
indicate an unacceptable impact to the patient, additional or alternative security measures should
be implemented and assessed. Threshold and objective parameters should be considered for
52
each metric (there may be cases where threshold parameters may be sufficient). Identifying these
parameters and monitoring for trends or outliers will allow emergency personnel to take appropriate
actions prior to an undesirable event. Such metrics would be useful to ensure resiliency. Step 4
results in the identification and assessment of relevant performance metrics by stakeholders that
further assist in understanding and monitoring the health of the enterprise.
Below, we provide an example set of performance metrics to be used for the protection
and resilience of CIs or dependent resources is provided in Tables 3 and 4.
Table 3. Reference Metrics for Critical Infrastructure/Dependent Resource Protection
53
Table 4. Reference Metrics for Critical Infrastructure/Dependent Resource Resilience
4.2.4 STEP 5: ASSESS MULTIPLE DIMENSIONS/PERSPECTIVES [CI-HHM]
[Steps 5 and 6 are closely linked. Step 5 details the risk-assessment process using HHM which is
required to calculate the Systems Security Effectiveness Index (SSEI), discussed in Step 6.]
This extensible CI/DR-HHM is provided with hierarchical and dimensional categories to
allow the CI/DR owner/operator to perform a risk-assessment of his/her infrastructure. Each
category (threats, vulnerability, protection, resiliency, and interdependency) is used by the
stakeholders to assess the security measures currently in place or proposed. Each stakeholder
responds to a series of the same questions from the perspective of their own discipline (e.g.
engineer, IT specialist, doctor/nurse, hospital administrator, etc.). This includes a combined
stakeholder threat and vulnerability analyses, for example, to determine the extent to which each
discipline effectively implements measures to reduce vulnerabilities, employs threat modeling,
plans for protection and resiliency, and considers interdependencies of other CIs and relevant
resources. The strength (or weakness) of security measures employed by an organization is
54
calculated based on a combined stakeholder risk-assessment of each CI/DR-HMM category. The
quantified results identify areas of deficiency, thus implying areas where improvements can be
made. The CI owner or dependent resource facilitator should evaluate (weight and priority) each
CI/DR-HHM category per their risk tolerance and goals.
Figure 2 illustrates the third order (hierarchical) graphical representation of the CI/DR-HHM,
with general weights uniformly distributed among its five categories. Adjacent to each sub-
category is the max weight a CI/DR owner/operator would self-assess the effectiveness of the
security measures they have in place. The decision-maker combines the results of the risk-
assessment completed by multiple stakeholders (internal and external), such as risk managers,
engineering, IT, and medical professionals to calculate the SSEI, described in Step 6.
Figure 2. HHM for Critical Infrastructure or Dependent Resources (CI/DR-HHM)
55
Using the CI/DR-HHM categories provided in Figure 2, relevant questions should be devised by
the organization and each question should have a measurable component for monitoring and
improvement. Qualitative responses to questions such as “do we have measures in place to
protect (blank)” (yes/no); “if so, what are they and are they sufficient?” Table 5 provides a general
CI/DR-HHM scale to score the risk-assessments for each category. A general SSEI scale was
developed for this study to illustrate the concept. [Table 5 and 6].
Table 5. CI/DR-HHM SSEI Scoring Scale (by Category)
Categories are identified as the main variables within the CI-HHM (threats, vulnerabilities, protections, resilience, and
interdependencies). Each of the five CI subset categories can have a maximum value of 20 percent (0.20).
A CI or enterprise can have a strength/weakness value per category in the range from 0 – 20
percent (0 – 0.20) as shown in Table 5. This weight or value implies that the enterprise has
implemented security measures (for that category) to a certain level of effectiveness in accordance
with their value proposition or goals. The results from the CI/DR-HHM category assessment
ultimately contribute to the overall SSEI “score” [Table 6] or level of the strength/weakness of an
organization’s security posture. Subsequently, the SSEI is used within the BBN analysis to
estimate impact. This step results in an understanding of specific areas of strength and weakness
of the enterprise and facilitates the ability to better allocate resources to security measures
identified as deficient so as to reduce negative consequences.
56
4.2.5 STEP 6: ASSESS STRENGTH/WEAKNESS [CALCULATE THE SSEI]
The SSEI is a calculated value that indicates/quantifies the risk management steps taken to reduce
the probability of a successful attack. Emergency management personnel or decision-makers are
to assess their effectiveness index based on the degree to which they implement measures and
reduce risk identified in the CI/DR-HHM categories [Figure 3]. Security measures should include
people, process, technology, e.g., “what, if any, security measures do we have in place, in the form
of people, processes, and technology, to detect, deter, neutralize, and reduce cyber/physical
attacks?”
Table 6. CI/DR-HHM SSEI Scoring Scale (Total)
The individual scores of the five categories are calculated from Figure 3 and Table 5, then combined for the overall CI-
HHM score. This total will be used to select the current effectiveness level of the SSEI in Table 6.
Table 7 illustrates scores elicited from a Department of Energy (power) engineering expert.
The CI/DR-HHM risk-assessment scores resulted in an overall SSEI score of 0.745 (75%) out of a
total possible score of 1.0 (100%). This particular CI owner, with appropriate stakeholders,
assessed their category relative effectiveness scores as follows: Threat (0.155 of max possible
0.20), Vulnerability (0.120 of max 0.20), Protection (0.178 of max 0.20), Resilience (0.156 of max
0.20) and Interdependency (0.136 of max 0.20). Table 4 denotes that a score of 0.745 falls in the
range of “good security posture.”
57
Table 7. Area of Improvement/Deficiency (Calculated SSEI)
Table 7 also identifies a difference score (column 3), which denotes area or room for
improvement. Given the overall score of 0.745, there is a total area of improvement of 0.255.
Specific areas can be identified to improve as the results are incorporated into the BBN model,
e.g., the Vulnerability category risk-assessment resulted in a difference score of 0.080 (having the
highest difference score). With an overall SSEI of 0.745, the BBN evaluation infers a “degraded”
impact to the patient. To improve this potentially unacceptable impact, the CI operator would use
the difference scores to take appropriate measures to increase overall security effectiveness,
58
ultimately improving their protection and resiliency. Further explanation is provided in BBN section
to follow (Step 7).
The examination of dimensional (category) elements of the CI/DR-HHM is critical to the overall
comprehensive security effectiveness evaluation. This research reveals that societal,
environmental, legislative, and stakeholder perspectives and actions contribute to either
strengthening or weakening protection and/or resiliency measures. An example to assess security
measures from a dimensional (stakeholder) perspective follows.
Example: HHM-Stakeholder Dimension: The questions in Table 8 should be asked from the
perspective of each stakeholder (engineer, IT professional, CI owner/operator, Physical security,
etc.).
Table 8. Exemplar Stakeholder Question Categories
A complete risk-assessment would follow the same logic and questioning from the perspective of
other dimensions, e.g., for the legislation/governance/policy dimension, “are there
laws/standards/policies in place (in the form of people, processes, or technology) that enable or
prevent our ability to detect, deter, neutralize, or reduce cyber/physical threats?” If so, what are
they and are they strategically employed to protect our security goal(s)? This step exits with an
SSEI score to be incorporated next into the BBN analysis.
59
THE MODEL
4.2.6 STEP 7: ASSESS IMPACT LIKELIHOOD [CONSTRUCT THE BBN]
In this study, a Bayesian Belief Networks (BBN) are generated illustrating the dependencies and
potential impacts of successful penetrations targeting CIs. The BBN is used here for its ability to
account for uncertainty and limited available data of CI probability of attacks and
interdependency/impact data. In general, BBNs can be used as visual representations of physical
and/or logical access into and within an enterprise, information system network, CI, or dependent
resource.
A BBN attack graph is provided at its highest level of nodal hierarchy, mapping the CI
interdependencies of an Healthcare and Public Health (HPH) CI sector element (e.g., hospital).
Figure 5 is offered as a simplified example to help understand and elucidate this research’s use of
BBN. The fundamental question for analysis is “what is the probability of a hospital patient’s
degraded health (with the possibility of death) given an attack on the power plant and/or the water
facility on which the patient ultimately depends?” This is determined by identifying through expert
judgment or historical data the marginal probability of an attack on nodes B, C, and D; and
subsequently calculating the joint probability to determine the potential impact to node E (using
Bayes Theorem). Upon calculating the probability of an attack on the hospital, that assessment is
propagated toward computing the probability of its associated links (F and G). The joint probability
of nodes F and G is then calculated to assess the vulnerability of H, the hospital patient’s degraded
health or death. Netica BBN software uses the Joint Tree algorithm to make inferences that
propagate calculated probabilites to adjoining nodes.
The assessment of each node is iteratively improved given updated data/knowledge for
that node, thus continuously reducing the uncertainty and adding more information fidelity for
60
decision making. Although this study considers each CI as a black box, it should be noted that one
will increase the fidelity of a node by examining the hierarchy within each node. Internal to each
node one would consider an aggregate of factors such as security measures currently in place,
historical attack data that may be available for that node, etc. – ultimately providing additional
insight into the “strength” weight or security effectiveness level for that node – assessing it to be
less/more vulnerable to penetration.
Figure 5. Simplified BBN
For this study, the proof of concept is demonstrated by using historical and relative notional data
(prior probabilities), while the unknown values are calculated through the Bayesian software
simulation tool Netica v5.15 to infer the CI interdependency impacts to dependent resources.
The case is considered where essential interdependent CIs to the hospital have performed
their risk-assessment of security effectiveness per the CI-HHM provided and have scored
61
themselves accordingly. The model structure and preliminary results were vetted by medical
professionals to confirm the model and various scenarios correctly represented their expectations.
The Conditional Probability Tables (CPT) and prior probabilities used in the hospital patient
healthcare BBN model were generated using data obtained from combined sources: medical
professionals, NIPP, DoE, DHS, Verisign, SSP, Verizon Breach Reports, Symantec, and EPA
along with best estimates and theoretical data from scenario analysis. Illustrated in the Figure 7
BBN, are various security effectiveness states of the CIs, given a successful DoS Attack or
No_Attack (on Power CI), resulting in either No_Effect, Partial_Shutdown, or Complete_Shutdown.
The following definitions provide further understanding of the “what-if” scenario analysis model:
No_Effect is defined as an event/attack having no significant impact/disruption, while a
Partial_Shutdown indicates that the main source has been impacted and services are only being
provided by the backup or a temporary alternate source. A Complete_Shutdown indicates that
both the main source and the backup are no longer providing service.
In Figure 7, the basic structure of the BBN with links is illustrated from the interdependent CIs
and their association to the hospital, subsequently noting the links from the hospital to the medical
devices on which a patient may be dependent to sustain life. Also noted, the network with nodes
that indicate a successful Attack or No_Attack on a CI, highlighted in red.
62
Figure 6. Representation of BASE m2d Model of DoS attack on CIs (w/o SSEI)
The CI_DoS Attack nodes in in Figure 6 are shown in red. Upon compilation, the dependent
nodes are then calculated to assess the potential impact to the hospital and subsequently to the
patient. The patient is assumed to be in the ICU and totally dependent on the medical device
(dialysis, ventilator, etc.). This model structure allows one to assess the impact to either the
hospital or patient target node of interest. Additional nodes can be added, ultimately adding to the
complexity of the interdependent nature of the CI, enterprise or organization.
The estimated risk-assessment from each CI is now folded into the SSEI nodes indicating the
CI strength or weakness. Until the SSEI rating/score is entered, the BBN model assumes a
uniform distribution, essentially stating that the score is unknown at the time of compilation. Upon
knowing/evaluating the respective CI SSEI or posture, that value is inserted as a Finding or as
Evidence in the model. However, the other CIs will be estimated or varied to perform an
appropriate “what-if” scenario analysis. As more evidence or data is known or observed, the
Water
No_Effect Partial_Shutdown Complete_Shutdown
100 0 0
Power
No_Effect Partial_Shutdown Complete_Shutdown
100 0 0
Communications
No_Effect Partial_Shutdown Complete_Shutdown
100 0 0
Hospital
None Limited_Service No_Service
100 0 0
DoS_Attack_Power
No_Attack Attack
100 0
DoS_Attack_Water
No_Attack Attack
100 0
Ventilator
None Degraded Out_of_Service
100 0 0
Dialysis_Machine
None Degraded Out_of_Service
100 0 0
DoS_Attack_Comm
No_Attack Attack
100 0
Ventilator_Patient
None Degraded Critical
100 0 0
Dialysis_Patient
None Degraded Critical
100 0 0
63
results of the model are improved. Performing this step results in estimating the likelihood of
impact to a patient given a cascading failure from a DoS attack on a CI.
Figure 7. Representation of SSEI Analysis given DoS Attack on Power CI
BASE m2d allows the decision-maker to assess from CI or dependent resource, i.e. “illustrate how
the CI’s SSEI strength/weakness potentially impacts the hospital or the patient.” An operator could
go further to assess or determine “what is the minimum SSEI one could have so as to not have a
critical impact?” The scenarios to be evaluated are numerous, each potentially enabling the
decision-maker to make more informed and proactive improvements for better protections.
Water
No_Effect Partial_Shutdown Complete_Shutdown
15.9 40.9 43.2
Power
No_Effect Partial_Shutdown Complete_Shutdown
47.9 31.3 20.8
SSEI_Water
Excellent Good Fair Poor
0 0 0
100
SSEI_Power
Excellent Good Fair Poor
16.7 25.0 50.0 8.33
SSEI_Communications
Excellent Good Fair Poor
0 0 0
100
Communications
No_Effect Partial_Shutdown Complete_Shutdown
39.8 28.9 31.3
Hospital
None Limited_Service No_Service
31.8 22.7 45.5
DoS_Attack_Power
No_Attack Attack
0 100
DoS_Attack_Water
No_Attack Attack
50.0 50.0
Ventilator
None
Degraded
Out_of_Service
17.3
23.2
59.5
Dialysis_Machine
None
Degraded
Out_of_Service
37.6
19.2
43.2
DoS_Attack_Comm
No_Attack Attack
50.0 50.0
Ventilator_Patient
None
Degraded
Critical
17.3
23.2
59.5
Dialysis_Patient
None
Degraded
Critical
37.6
19.2
43.2
64
Figure 7 illustrates how the use of SSEI HHM (blue nodes) assessments can be used to make
decisions to ultimately improve a CI element’s security posture. Upon determining the SSEI score
from the risk-assessment, the CI-HHM BBN model was used to evaluate impacts to a CI facility,
dependent hospital, or patient given a successful DoS. Figure 7 also illustrates how the Water CI
and Communication CI have experienced a successful penetration, which yields a “Poor” relative
effectiveness index. The model indicates that given a “Poor” index, the probability of
Complete_Shutdown on Water and Communications is 43.2% and 31.3%, respectively, given a
successful DoS attack on Power (due to their interdependence). Additionally, the impact to the
hospital is noted as having a 45.5% probability of providing “No_Service” to dependent resources
given the CI vulnerabilities. Subsequent actions by the hospital to improve the index should result
in a lower likelihood of providing “No_Services” to the hospital.
Further analysis revealed a 43% probability of potential “critical” impact to the patient. A
“critical” impact score to the patient indicates a life-threatening result due to the grave nature of the
patient’s condition and their total dependence on the medical device that is providing services.
Given an unsatisfactory potential patient impact score, the SSEI risk-assessment (difference
scores) that was previously performed is re-assessed. This re-assessment specifically seeks to
target/improve security measures that would strengthen or reduce the impact to the target goal
(patient). This evaluation is an iterative process with the goal of continual, targeted, security
effectiveness improvement.
Decisions can be made given various trades from the scenario analysis, taking into account
the security goal, risk priorities, and budget constraints. The “difference scores” indicated in the
SSEI table allow the CI operator to strategically target specific areas of improvement for better
protections.
65
4.2.7 STEPS 8-10: DECISION ANALYSIS
The decision-maker has now examined, based on his security goals, “What can go wrong and its
impact?” (steps 1-6), “How likely is it to go wrong?” (step 7), and “What are the possible
outcomes?” (Steps 1-7). From Step 7, we have learned the likelihood of impact to the patient in
the event of a CI DoS attack. Step 8 -10 uses this information to make strategic decisions based
on relevant goals. Upon estimating the risk to the patient, as categorized in the model (Step 8), the
decision-maker proceeds to Step 9 to determine if the risk is acceptable to sustain life until
alternative protective or resilient measures take effect. Step 10 responds to the respective answer:
If “yes,” re-assess periodically for new threats or assessments; If “No,” implement new/additional
measures based on self-assessment risk analysis (difference scores).
The BASE m2d methodology seeks to empower emergency management personnel with
the ability to make risk-informed decisions given the realities of the world we live in today –
uncertainty; sophisticated adversaries; limited data; and adaptive, complex, and interdependent
infrastructure. With the insight gained from using the multi-dimensional approach, we have
potentially uncovered otherwise hidden areas of risk. Coupled with BBN, the user can
operationalize the stakeholder information to make strategic decisions.
CHAPTER 5 - DATA ANALYSIS AND RESULTS
5.1 ANALYSIS OBJECTIVES
This section describes the analysis of data gathered and presented by this research. Data analysis
consisted of analyzing demographic, descriptive data, inferential data, response data, and reliability
data (i.e., Cronbach alpha). Statistical software (i.e., Minitab, SPSS and Netica) was employed to
66
perform the necessary analysis. There were two main objectives identified for the analyses
performed in this research: 1.) Reliability and Validity of Survey Instrument; 2.) Validity of
Conceptual Framework. Ten (10) respondents/representatives from ten distinct hospitals
participated in the online survey. The analysis revealed internal reliability and validity of the survey
instrument and the framework. The findings of each are detailed in the following sections.
5.2 DEMOGRAPHIC DATA
Demographic data were collected on respondents on specific job function in the medical
profession, with options of physician, nurse practitioner, or administrator. Research revealed that
any of these professions would provide relevant data regarding the objectives of this study. Years
of experience and experience in ICU data were also collected.
Thirteen hospitals were solicited for expert knowledge on risk management, metrics,
procedures, and policies regarding CI service interruption impacts to patients. Ten hospitals
responded by completing a 60-question electronic survey, to include comment sections of
voluntary information allowing for elaboration of selected answers or to provide additional details.
A majority (7 of 10) of the survey respondents were tenured medical professionals (10 years or
more experience in a medical field). All respondents were identified as personnel experienced and
qualified to speak on behalf of their hospital.
67
Figure 8. Survey: Years of Experience in Medical Field
Figure 9. Survey: Medical Field Profession
Figure 10. Survey: Experience in Intensive Care Unit (ICU)
68
In this research, experts are loosely defined as a nurse, physician, or administrator knowledgeable
in the hospital’s risk management practices, and having a clinical understanding of patient impact
given specific service interruptions. Respondents experience in ICU was relevant to understand
their appreciation of emergency equipment operations and significance to patient’s survival.
Although ten experts were surveyed, five experts are usually sufficient for most elicitation efforts.
Clemen and Winkler (1985) discussed that data saturation can occur and that diminishing returns
have been observed when including additional experts.
5.3 METRICS
Basic and publicly available metric data was elicited from respondents for two purposes: 1)
understand knowledge of medical professional staff of hospital protocols and procedures regarding
measures used to trigger alternate systems, and 2) Calibration of expert judgment information, if
desired. Questions and responses are summarized below.
What metric is used to trigger backup POWER generator?
69
What metric is used to trigger backup WATER supply?
What metric is used to trigger alternate COMMUNICATIONS?
In summary, it is interesting to note elicited responses regarding knowledge of metrics used: 50%
were not aware of metrics used to trigger alternate power sources or generators; a disparity in
knowledge existed for metrics used for water; and more than 70% indicated they had no
knowledge of alternate measures or metrics for communications given a service outage.
70
As indicated in this research, metrics are imperative to demonstrate emergency preparedness
for the public healthcare community; just as important is assessing those measures periodically
and ensuring that the staff is aware and trained to respond accordingly in the event alternate
comms are needed.
5.4 DESCRIPTIVE DATA
Data were collected from experts on likelihood of CI service disruption impacts to patients
depending on the following medical devices: cardiac equipment, dialysis systems, and
oxygen/ventilators. Ten medical professional respondents from different hospitals provided expert
judgment on likelihood of impact (critical, degraded, no impact) given a CI (power, water, comms)
service disruption.
A summary of analysis was performed on data collected from the respondents. The data was
grouped by CI service disruption (power, water, comms) against likelihood of impact (critical,
degraded, no impact) to patients depending on various medical equipment (cardiac care, dialysis,
ventilator). The results were used to validate the behavior of the BBN model.
The data was collected from the respondents used a 5 point Likert scale that correlated to
probability distributions as follows:
1 2 3 4 5
Very unlikely Unlikely Need More Info Likely Very Likely
(0-20%) (21-40%) (41-60%) (61-80%) (81-100%)
Power Disruption Impact: Respondents were mostly consistent in their responses regarding
the likelihood of “critical” impact of disrupted power to medical devices. Respondents tended to
agree (between likely and very likely) that any disruption of service to power (limited or complete
shutdown) would have a higher likelihood of having a “critical” impact on a patient depending on
71
dialysis, cardiac care, and/or ventilator. More variance was noted among respondents in regards
to assessing “degraded” impact to patients given a service disruption. Respondent ability to
assess “degraded” impact to patient given power disruption exhibited a large variance, indicating
responses in this category to be inconclusive. Nevertheless, it was noted that fifty percent of the
respondents selected “need more info” to determine the likelihood of impact to a cardiac care
patient given limited power. Respondents tended to agree that “no impact” to a patient would be
less likely (between very unlikely and unlikely) given service disruption in power to any of the
medical devices. This was consistent with the BBN model results.
Water Disruption Impact: Respondents were mostly consistent in their responses regarding
the likelihood of “critical” impact of disrupted or contaminated water supply. Respondents tended to
agree (between likely and very likely) that any disruption of service to water (limited or complete
shutdown) would have a higher likelihood of having a “critical” impact to a patient depending on
dialysis, cardiac care, and/or ventilator. Respondents had a general agreement and a tendency
toward unlikely “degraded” impact to patients given water disruption, although a variance spread
was dually noted in this category. A stronger agreement among respondents (between very
unlikely and unlikely) was noted in assessing likelihood of “no impact” to patients given a water
disruption/contamination. This was consistent with the BBN model results.
Communication Disruption Impact: Respondents were generally consistent in their
responses regarding the likelihood of “critical” impact of disrupted comms unlikely to very likely.
Meaning, each respondent was consistently explicit that disrupted comms would have some
measure of impact to patient care. This category may have been less intuitive to respondents
which is indicated by the disparity in their response. Comms is represented here as the electronic
72
response system used to communicate with emergency staff to provide the status of patients
connected to a medical device, such as an alarm to notify service has been disrupted. If
communication systems are down, medical professionals may be unaware that help is needed and
services are no longer being provided or have been degraded. Respondents tended to agree
(between unlikely and very unlikely) that any disruption of service to comms (limited or complete
shutdown) would have a higher likelihood of having a “degraded” impact to a patient depending on
dialysis, cardiac care, and/or ventilator. More variance was noted among respondents in regards
to assessing “no impact” to patients given a comms service disruption, indicating more info would
be needed to determine increase or decrease in “no impact” likelihood. This was consistent with
the BBN model results.
5.5 RELIABILITY AND VALIDITY OF SURVEY INSTRUMENT
To determine if the results of the survey instrument are reliable and valid, respondent data is
evaluated against the data produced by the tool (instrument). Specifically, did the survey measure
what it was intended to measure. In review, the instrument was evaluated as follows:
RELIABILITY ▪ INTERNAL CONSISTENCY or Homogeneity using a Cronbach coefficient (α >0.7)
o Measures the extent to which a technique, experiment, or measuring procedure
assess the same characteristic or quality
▪ INTRARATER RELIABILITY
o Measures the extent to which multiple respondents agree in their ratings of given
items.
73
Results revealed that the survey instrument tested reliable in its ability to assess the impact to a
patient given a service disruption in power, water, and communications. Each category
demonstrated a Cronbach alpha as follows:
➢ Critical α = 0.936
➢ Degraded α = 0.924
➢ No impact α = 0.931
These results indicate the strong internal consistency of the tools’ ability to measure the
aforementioned attributes.
To determine the intrarater reliability, the Intra-class Correlation Coefficient (ICC) was used.
This statistical measure the proportion of variance of an observation due to between-subject
variability in the true score (Fink 2003).
➢ Critical ICC = 0.932
➢ Degraded ICC =0 .929
➢ No impact ICC = 0.925
The results indicate consistent responses between the respondents.
VALIDITY
▪ CONTENT VALIDITY o Measures the extent to which the question/items thoroughly and appropriately
assess the characteristics or qualities it purports to measures.
▪ FACE VALIDITY
o Measures the appearance of the metric/question on the surface.
74
Content validity is a subjective measure of how appropriate items or scales seem to a set of
reviewers identified as Subject Matter Experts (SMEs) (Litwin 2003). It typically involves an
evaluation of the survey’s content to ensure it includes relevant information or questions. Content
validity is not quantified with statistics (Litwin 2003). Instead it is an opinion from subjective
experts. The survey was reviewed by administrators of each hospital for relevance before
appointing an appropriate Respondent. The survey was deemed relevant and appropriate for its
purpose.
Face Validity is determined by an observer with an untrained eye and is considered a casual
assessment of the appropriateness of the survey instrument (Litwin 2003).
5.6 VALIDITY OF CONCEPTUAL FRAMEWORK
A major goal of this study was to develop a model that is valid in assessing the ultimate purpose of
evaluating system security effectiveness of CIs and dependent resources, given noted
interdependencies. Events and actions that occur from a dependent or linked CI have the ability to
influence the likelihood of occurrence and impact on an adjoining dependent resource. It is
demonstrated here that this phenomena can be modeled using BBN nodes with various alternating
states. The direction of influence is identified with parent-child or CI-hospital and/or hospital-
medical device references as required by one of the rules of BBN using Directed Acyclic Graphs
(DAG). Although the direction of influence and dependence often flows from parent to child,
inferences can be made in the opposite direction. The model learns from this data and can
generate Conditional Probability Tables (CPTs) that are often used to evaluate the model
performance. The CPTs used in this research were generated from historical and relational data.
As mentioned previously, this conceptual framework is validated with the use of data identified in
the Data Collection section and correlated with data provided by experts.
75
5.7 THREATS TO INTERNAL VALIDITY
Threats to validity for this research include the following:
• Internal validity demonstrates a causal relationship between variables. Medical
professionals are influenced (bias and overconfidence) by many factors, and this is often
reflected in their responses. The approach used to mitigate this threat to internal validity
was to take care in training or calibrating the expert with the use of mixed method
techniques (as described in the Research Methodology section). Respondents were also
allowed to provide open comments to elaborate or ask questions, if needed. Clear
instructions and training are imperative to mitigating this threat.
• Reliability of the measurements can threaten validity. The data collection instruments
included: knowledge questions to establish the credibility of the respondent, consistent
measurement scales, clear and unambiguous questions, concise and efficient
questionnaire design, and sufficient time to fill-out the questionnaire (Babbie, 1990,
Sudman and Bradburn, 2004; Valerdi, 2005).
5.8 THREATS TO EXTERNAL VALIDITY
External validity refers to the ability to apply the research results to other contexts or domains.
The external validity of this study extends beyond CIs and hospitals. Another application within the
space community is to evaluate potential impacts to satellites given a successful attack to
interdependent ground stations. The general concept has extensibility to assess and evaluate how
a successful threat to a third party’s vulnerability can impact a primary or secondary source and
vice versa.
76
CHAPTER 6 – CONCLUSION
This research establishes a systematic, multi-dimensional, quantitative, metric-based framework
required to effectively assess, measure, and ultimately improve an organization’s security posture.
The utility of multi-dimensional models such as HHM and BBN and applying them to CI cyber-
physical security protection and resiliency is examined.
To achieve greater security effectiveness for CIs, a systematic approach, using Systems
Engineering principles, within the operational environment by first identifying security goals and
objectives based on what is to be protected was suggested. Second, identify all paths that lead to
the CIs that need protecting, including internal and external access and dependencies (via people,
processes, technology, infrastructure, i.e., the entire enterprise). Third, articulate what security
means are implemented from the perspective of all stakeholders. In the absence of this type of
systematic approach, organizations, enterprises, and infrastructures will remain vulnerable. This
research postulated that the understanding and influence of the strengths/weaknesses of the
enterprise are enhanced with the use of inferential statistics coupled with multi-dimensional,
metrics-based analysis. It also is important to position security professionals and other key decision
makers to measure the effectiveness of implemented security controls. Further, this framework
and methodology empowers leaders to make more informed decisions as to where resources
should be focused for more effective security.
The methodology used to address this complex problem of improving cyber-physical
security protection of the enterprise, or specifically in this case the nation’s CIs, must expand
beyond traditional approaches used today. Further, organizations, CI owners, and operators must
have the ability to assess the effectiveness of the security program they put in place. Measures of
effectiveness (MOE) identified in the proper context (based upon security goals and the operational
77
environment), using relevant performance metrics for proactive monitoring and vulnerability
assessment, can be used to not only understand security posture but also to highlight deficiencies
that would otherwise prevent the making of informed decisions toward the implementation of more
cost-effective solutions.
6.1 CONCLUSION WITH RESPECT TO STUDY HYPOTHESES
In review, the following hypotheses were asserted:
Hypothesis 1a: Probabilistic reasoning and a systems-thinking based framework can be combined to assist in the overall evaluation (strength or weakness) of CI and/or dependent resources security effectiveness. Hypothesis 1b: Probabilistic reasoning and a systems-thinking based framework can be combined to quantifiably evaluate security effectiveness of Protection and Resiliency (P/R) for CIs and their dependent elements.
It was shown that HHM (systems-thinking based framework) and BBN (probabilistic reasoning)
could be combined to demonstrate the strength or weakness of CI security effectiveness by
implementing the HHM qualitative component to evaluate various elements of the CI from multiple
dimensions, and using the BBN module of the framework to dynamically assess the potential
impact of a threat in accordance with available data and identified dependencies. It was further
determined that the hybrid model demonstrated the ability to quantify the effectiveness of
protection and resiliency for CIs with the use of metrics, the SSEI, and the inherent nature of BBNs.
6.2 CONCLUSION WITH RESPECT TO STUDY QUESTIONS
In review, the following questions were asserted for this research:
Question #1: How can the assessment of security effectiveness of CI interdependencies and
vulnerabilities be modeled proactively (before occurrence or penetration) for improved decision-
making?
78
The use of BBNs allowed for the most appropriate assessment of indirect consequences of a direct
attack. The very nature of BBN development is to establish hierarchical dependencies, often to
multiple orders (3rd, 4th order, etc.). It was demonstrated through scenario analysis within the
framework and a hospital case study that a successful DoS attack on a CI (power, etc.) could be
modeled proactively (before occurrence or penetration) for improved decision-making
Question #2: How can combining HHM and BBN facilitate the assessment of relative
effectiveness of CI security measures?
The BASE m2d framework integrated both qualitative (HHM) and quantitative (BBN)
modules/components to exercise the SSEI concept, allowing a CI owner/operator the ability to self-
assess the current security posture of their infrastructure based on their security goals and
tolerance. This self-assessment with the conceptual framework enables the CI to ultimately make
improvements to prevent or mitigate (direct and indirect) negative impacts.
Question #3: What metrics are used by hospitals to trigger auxiliary systems in the event of a
shutdown (partial or complete)? What metrics, if any are used to warn, prevent, or absorb CI
service interruptions?
As a result of the Respondents survey, it was surprisingly noted that many medical professionals
were unaware of any metrics used to trigger auxiliary systems in their respective hospitals.
6.3 DISCUSSION
In this research, the question “how secure am I?” is not asked. Although a relevant question, a
more realistically attainable and measurable question is posed– “how effective are the security
79
measures I have put in place?” More specifically, “what systematic construct or metrics have we
employed to assess that effectiveness in accordance with our value proposition or security goals?”
For example, if you have removed unnecessary accesses (via physical hardware or personnel
(root access)), you have essentially reduced your attack surface; in turn, you can measure the
effectiveness of that security implementation. Although many organizations work diligently to
ensure they are in compliance with the latest standards, it has been proven by our adversaries that
being in compliance does not guarantee security.
To effectively achieve the stated research goals, this research proposed the integration of
two hierarchical techniques to enable a qualitative and quantitative assessment of security
measures. This framework provides a risk assessment via scenario or what-if analysis to inform
the decision-maker on where best to allocate proper resources that maintain a specific and
appropriate level of service to preserve human life in the event of a CI failure due to an attack
vector (partial shutdown or complete shutdown). In addition, it is asserted that metrics should be in
place to account for minimum mean time between failures to ensure resiliency measures are
effective. For example, a back-up generator must be triggered within a certain timeframe to ensure
a ventilator patient does not asphyxiate due to oxygen deprivation.
Additionally, the significance of attack graphs and understanding attack paths to protect an
enterprise security goal is a strategic and important step in effective and efficient use of resources.
Attack paths/graphs are to be produced from various scenarios within the CIs’ operational
environment, to include interdependencies with other CIs. BBNs are then generated from each
attack graph to identify potential areas of vulnerability. HHM has been used to identify dimensional
variables (temporal, geo-spatial, legislative, societal, stakeholders’ perspective) from which
strengths and weaknesses of each CI node are to be evaluated. Finally, a simplified BBN threat
scenario is provided that is used to demonstrate and evaluate the CI security effectiveness per the
80
identified metrics. The overall methodology is iterative to incorporate new data or knowledge (via
BBN), to produce results with greater accuracy and fidelity; this construct is scalable and extensible
in that this method can be used for the largest CI to the smallest architectural element (network or
enterprise) and various CI domains; and a general process is provided for repeatability.
This study expands on knowledge, experience, and recommendations offered by previously
documented research. The hybrid methodology assesses the potential impacts to patients,
medical devices and the emergency preparedness of a healthcare facility given a CI service
disruption. Additionally, it provides a holistic, strategic, quantitative, and measurable approach that
permits one to perform relative security effectiveness analysis in the face of uncertainty and where
limited data prevents necessary measures from being executed to ensure proper protection and
resiliency of the enterprise.
I bound and strategically target the problem-solution space by defining the operational
environment and identifying the security goals that are to be protected. This research
postulates that the understanding and influence of the strengths/weaknesses of the enterprise are
enhanced with the use of inferential statistics coupled with multi-dimensional, metrics-based
analysis. Standardized use of the SSEI would allow CIs and/or key resources to maintain and
communicate a certain “acceptable” index that merits or ensures an agreed-to level of service to its
dependent resources.
It is acknowledged that current methodologies used to address the complex problem of
improving cyber/physical security protection of the enterprise, or specifically in this case the
nation’s CIs, must expand beyond existing traditional approaches. Most security methods used
today are considered from a single-dimension. This is normally accomplished by protecting
architectural elements or components (network of routers, switches, servers) from cyber-attacks,
i.e., by configuring firewalls, implementing policies, and training users. Although these techniques
81
demonstrate a noble effort, they have proved to be neither sufficient nor effective. Further,
organizations, CI owners, and operators must have the ability to assess the effectiveness of the
security program they put in place. Measures of effectiveness (MOE) identified in the proper
context (based upon security goals and the operational environment), using relevant performance
metrics for proactive monitoring and vulnerability assessment, can be used to not only understand
security posture but also to highlight deficiencies that would otherwise prevent the making of
informed decisions toward the implementation of more cost-effective solutions. Finally, this
approach allows organizations, CI owners, and operators the ability to assess and reduce
vulnerabilities within and across the security domain to which they interface and are responsible.
CHAPTER 7 - FUTURE RESEARCH
The SSEI scale proposed in this research could be improved, verified, and validated by CI
owners/operators and further assessed against previous cases of enterprises or CIs that have
experienced DoS attacks to test predictability and reliability. This research also recommends that
for a complex, interdependent system of CIs to effectively provide critical services to dependent
resources, more effective and efficient standards need to be implemented. Standards that
mandate CIs communicate (share information) across CIs and to those that depend on their
services, in accordance with a security effectiveness taxonomy understood by the impacted
community of stakeholders. The SSEI concept introduced in this research, if further developed,
would allow CIs to communicate in a common language at a confidential or sensitive information
level, if necessary. This would allow appropriate security measures to be considered from the
82
perspective of their own internal security effectiveness evaluation, as well as the external
interdependent sources security effectiveness levels/evaluation.
This research has laid the ground work for future studies in the area of understanding,
assessing, and improving system security effectiveness for CIP/R. The following
recommendations are offered as potential areas of research:
• The Systems Security Effectiveness Index can be furthered developed by generating a
more relevant scale of measurement. This research provided a general scale to
demonstrate the concept of the hybrid framework by equally dividing each category. For
example, further research can determine if a scoring range of .95 – 100 percent should be
considered ‘Excellent’, or a range of 0 - 0.50 should be considered ‘Poor’ security
effectiveness.
• The CI-HHM provided in this research established an equal scale for the variables
identified from the NIPP. Additional research could establish priorities for a specific CI
function (Water, Power, etc.) or specific enterprise in question and place relevant weights
using models such as AHP or MAUT.
• This conceptual framework was demonstrated using a hospital case study however, the
researcher believes the concept is extensible to other disciplines with varying threats
• Establish an SSEI ontology that can be generalized to a relevant community and
mandated to be shared.
83
REFERENCES
Adar, E., & Wuchner, A. (2005). Risk management for critical infrastructure protection (CIP)
challenges, best practices, & tools. Paper presented at the 8 pp.
doi:10.1109/IWCIP.2005.18
Alden, J. (2006) Measuring the “unmeasurable.” Perf. Improv., 45: 7–11.
Alqahtani, Abdulrahman, (2015) "Towards a Framework for the Potential Cyber-Terrorist Threat to
Critical National Infrastructure." Information and Computer Security 23 (5): 532-569
Annex, A., (2010) Infrastructure, N., & Plan, P. Healthcare and Public Health Sector-Specific Plan
Amass F. S., Bhunia, A. K, Chaturvedi, A. L., Dolk, D. R., Peeta, S., and Atallah, M. J. Advances in
Homeland Security Series: The Science of Homeland Security (Volume 1), West Lafayette, IN:
Perdue University Press, 2006 227 pp, introduction, notes, bibliography, index (hardcover)
Assessment of Key Risks for Hospitals and Healthcare Systems – Spring 2010,
<http://www.kpmg.com/US/en/IssuesAndInsights/ArticlesPublications/Documents/heal
thcare--‐risk--‐assessment--‐spring--‐2010.pdf>
Ayyub, B. M. (2001). Elicitation of expert opinions for uncertainty and risks, CRC Press.
Babbie, E. (2010). The basics of social research (5th ed.). Belmont, CA: Wadsworth Publishing.
Bayraktarli, Y. Y., J. Ulfkjaer, et. al.. (2005) On the application of Bayesian probabilistic networks
for earthquake
Bayuk , Jennifer and Ali Mostashari. (2013) "Measuring systems security." Systems Engineering: 1-
14.
Bensi, Michelle Terese. (2010) A Bayesian Network Methodology for Infrastructure Seismic Risk
Assessment and Decision Support
84
Biringer, B., E. Vugrin, et. al.. (2013). Critical infrastructure system security and resiliency, CRC
Press.
Bloomfield R , Chozos N , Nobles P . (2009) Infrastructure interdependency analysis: introductory
research review. Adelard LLP;
Boring, R., Gertman, D., Joe, J., Marble, J., Galyean, W., Blackwood, L., & Blackman, H. (2005).
Simplified Expert Elicitation Guidelines For Risk Assessment Of Operating Events.
(INL/EXT-05-00433). Idaho Falls, Idaho: Department of Energy, U.S. Nuclear Regulatory
Commission, Office of Nuclear Regulatory Research, Division of Risk Analysis &
Applications.
Burnside ES, Rubin DL, Shachter RD. (2004) Using a Bayesian Network to Predict the Probability
and Type of Breast Cancer Represented by Microcalcifications on Mammography” in:
Fieschi, M., Coiera, E., and Li, Y.J., Eds., Medinfo 2004, Proceedings of the 11th World
Congress on Medical Informatics, Sept. 7-11, 2004, IOS Press, 13-18.
Carmines, E. and R. Zeller, Reliability and Validity Assessment. Quantitative Applications in the
Social Sciences, ed. M.S. Lewis-Beck. 1979, Thousand Oaks, California: SAGE
Publications.
Chittister, Clyde C., and Yacov Y. Haimes. (2012) "Risk to cyberinfrastructure systems served by
cloud computing technology as systems of systems." Systems Engineering 15: 213-224.
Clemen, R. T. and R. L. Winkler (1985). "Limits for the Precision and Value of Information from
Dependent Sources." Operations Research 33(2): 427-442.
Cooke, R.M. 1991. Experts in Uncertainty: Opinion and Subjective Probability in Science
Cooke, R. M., & Goossens, L. H. (2004). Expert judgement elicitation for risk assessments of
critical infrastructures. Journal of risk research, 7(6), 643-656.
85
Cronbach L. J. (1971) "Test Validation," R.L. Thorndike (ed.) Educational Measurement
Washington, DC: American Council on Education
Department of Homeland Security, http://www.dhs.gov/healthcare-and-public-health-sector
Di Giorgio, Alessandro, and Francesco Liberati. (2011) "Interdependency modeling and analysis of
critical infrastructures based on Dynamic Bayesian Networks." In Control & Automation
(MED), 2011 19th Mediterranean Conference on, pp. 791-797. IEEE.
Dimase, D., Collier, Z. A., Heffner, K., & Linkov, I. (2015). Systems engineering framework for
cyber physical security and resilience. Environment Systems & Decisions, 35(2), 291-300.
Druzdzel, MJ and Van der Gaag, LC, 1995 “Elicitation of probabilities for belief networks:
combining qualitative and quantitative information,” Proceedings of the Eleventh Conference
on Uncertainty in Artificial Intelligence 141–148
Eusgeld, I., C. Nan, S. Dietz, (2011) ‘‘System-of-systems” approach for interdependent critical
infrastructures, Reliability Eng. Syst. Saf. 96 679–686.v
Eusgeld, I., D. Henzi, et. al.. (2008). "Comparative evaluation of modeling and simulation
techniques for interdependent critical infrastructures." Scientific Report, Laboratory for Safety
Analysis, ETH Zurich.
Executive Order 13636 (2013) Improving Critical Infrastructure Cybersecurity, President Barack
Obama
Executive Order 13010 (1996). Critical Infrastructure Protection. Federal Register. Vol. 61. No.
138.
Executive Order 13130 (1999). National Infrastructure Assurance Council, Federal Register, Vol.
64.
86
Executive Order 13231(2001) Critical Infrastructure Protection in the Information Age. Federal
Register. Vol.66.
Ezell, B. C. (2007). Infrastructure Vulnerability Assessment Model (I‐VAM). Risk Analysis, 27(3),
571-583.
Fink, A. (2003). The survey handbook, Sage.
Fink, A. (2003). The Survey kit:How to manage, analyze and interpret survey data. Thousand
Oaks, CA: SAGE Publications Ltd doi: 10.4135/9781412984454
Fink, A. (2003). The survey kit: How to manage, analyze, and interpret survey data, Thousand
Oaks, CA: Sage Publications, Inc.
Flandoli, F., E. Giorgi, et. al. (2011). "Comparison of a new expert elicitation model with the
Classical Model, equal weights, and single experts, using a cross-validation technique."
Reliability Engineering & System Safety 96(10): 1292-1310.
Forsberg JA, Eberhardt J, Boland PJ, Wedin R, Healey JH. (2011) Estimating Survival in Patients
with Operable Skeletal Metastases: An Application of a Bayesian Belief Network. PLoS
ONE 6(5): e19956.
Forsberg, J. A., Healey, J. H., & Brennan, M. F. (2012) A probabilistic analysis of completely
excised high-grade soft tissue sarcomas of the extremity: an application of a Bayesian
belief network. Annals of Surgical Oncology, 19(9), 2992–3001.
Fowler, F. J. (1995). Improving survey questions: Design and evaluation. Thousand Oaks, CA:
Sage Publications.
Fowler, F. J. (2009). Survey research methods (4th ed.) Thousand Oaks, CA: Sage Publications.
87
Frigault, Marcel. (2010) Measuring network security using Bayesian network-based attack graphs.
Ph.D. diss., Concordia University (Canada),
http://search.proquest.com/docview/794810164?accountid=11243
Gass, Saul I. 2005. Model world: The great debate-MAUT versus AHP. Interfaces 35, (4) (Jul):
308-312, http://search.proquest.com/docview/217112431?accountid=11243 (accessed
February 27, 2015).
Ghorbani AA, BagheriE. (2013)The state of the art in critical infrastructure protection : a framework
for convergence. International Journal of Critical Infrastructures 2008;4:215–44.
Grover, Jeff. (2013) Strategic economic decision-making using Bayesian belief networks to solve
complex problems. New York, NY: Springer
Haimes, Yacov Y. (1981) "Hierarchical Holographic Modeling." IEEE Transactions On Systems,
Man, and Cybernetics: 606-617.
Haimes, Yacov Y. and Chittester, Clyde G. (2005) "A Roadmap for Quantifying the Efficacy of Risk
Management of Information Security and Interdependent SCADA Systems," Journal of
Homeland Security and Emergency Management: Vol. 2: Iss. 2, Article 12.
Haimes, Yacov Y. (2004) “Risk modeling, assessment, and management”. Hoboken, N.J.: Wiley-
Interscience
Haimes YY,Horowitz BM, Lambert JH, Santos JR,Crowther KG, and Lian C. Inoperability input–
output model for interdependent infrastructure sectors. II: ase studies. Journal of
Infrastructure Systems,11;80–92.
Haimes, Y.Y., J. Lambert, Duan Li Duan Li, R. Schooff, and V. Tulsiani. (1995) “Hierarchical
holographic modeling for risk identification in complex systems. 1995 IEEE International
Conference on Systems, Man, and Cybernetics”. Intelligent Systems for the 21st Century.
88
Harrison, Keith and White, Gregory B. (2010) "An Empirical Study on the Effectiveness of Common
Security Measures." Lecture, 2010 43rd Hawaii International Conference on System
Sciences, Koloa, Kauai, Hawaii
Hayes, N. (Ed.) (1998). Doing qualitative analysis in psychology. Hove: Psychology Press.
Hokstad, P., I.B. Utne, J. Vatn,( 2012) Risk and Interdependencies in Critical Infrastructures: A
Guideline for Analysis, Springer.
Hubbard, D. W. (2009). The failure of risk management: Why it's broken and how to fix it. John
Wiley & Sons.
Hubbard, Douglas W. (2010) How to measure anything finding the value of "intangibles" in
business. 2nd ed. Hoboken, N.J.: Wiley.
Hubbard, Douglas W. (2016) How to measure anything in cybersecurity risk. Hoboken, N.J.: Wiley.
http://ics-cert.us- cert.gov/sites/default/files/Monitors/ICS-CERT_Monitor_Oct-Dec2012.pdf
http://www.dhs.gov/xlibrary/assets/NIPP_Overview.pdf
HTTP://WWW.DHS.GOV/NEWS/2013/07/18/WRITTEN- testimony-nppd-house-homeland-security-
subcommittee-cybersecurity
https://www.washingtonpost.com/world/national-security/russia-has-developed-a-cyber-weapon-
that-can-disrupt-power-grids-according-to-new-research/2017/06/11/b91b773e-4eed-11e7-
91eb-9611861a988f_story.html?utm_term=.89e606950738 (2017)
https://www.whitehouse.gov/the-press-office/2017/05/11/presidential-executive-order-
strengthening-cybersecurity-federal (2017)
https://www.healthcare-informatics.com/article/cybersecurity/exclusive-report-what-can-us-
healthcare-it-leaders-learn-wake-wanna-cry (2017)
https://www.cnet.com/news/petya-goldeneye-wannacry-ransomware-global-epidemic-just-started/
(2017)
89
Jha, Manoj K.(2009) "Dynamic Bayesian network for predicting the likelihood of a terrorist attack at
critical transportation infrastructure facilities." Journal of Infrastructure Systems 15, no. 1:
31-39.
Jaquith, Andrew. (2007) Security metrics: replacing fear, uncertainty, and doubt. Upper Saddle
River, NJ: Addison-Wesley.
Kahan, Jerome H.; Allen, Andrew C.; and George, Justin K. (2009) "An Operational Framework
for Resilience," Journal of Homeland Security and Emergency Management: Vol. 6: Iss. 1,
Article 83.
Kjølle, G. H., I. B. Utne, et. al.. (2012). "Risk analysis of critical infrastructures emphasizing
electricity supply and interdependencies." Reliability Engineering & System Safety 105:
80- 89.
Kohavi, R. (1995). A study of cross-validation and bootstrap for accuracy estimation and model
selection.
Kozik, Rafał, Michał Choraś, and Witold Hołubowicz. (2010) "Fusion of Bayesian and Ontology
Approach Applied to Decision Support System for Critical Infrastructures Protection." In
Mobile Lightweight Wireless Systems. : Springer Berlin Heidelberg.
Kuehn, N. M., Riggelsen, C., and Scherbaum, F. (2009). ―Facilitating Probabilistic Seismic
Hazard Analysis Using Bayesian Networks.‖ Seventh Annual Workshop on Bayes
Applications (in conjunction with UAI/COLT/ICML 2009).
Laconte, P., Y. Y. Haimes, et. al.. (1982). Water resources and land-use planning : a systems
approach: Proceedings of the NATO Advanced Study Institute on: "Water Resources and
Land-Use Planning," Louvain-la-Neuve, Belgium, July 3-14, 1978. The Hague ; Boston
Hingham, MA, USA, M. Nijhoff ; Distributors for the U.S. and Canada, Kluwer Boston.
90
Laskey, K. B., & Mahoney, S. M. (2000). Network Engineering for Agile Belief Network Models,
12(4), 487–498.
Lewis, T. G. (2006). Critical infrastructure protection in homeland security: defending a networked
nation, John Wiley & Sons.
Liberati, A. D. G. a. F. "<Bayesian Network-Based Approach to the Critical Infrastructure
Interdependencies Analysis.pdf>." IEEE SYSTEMS JOURNAL VOL. 6, (NO. 3): 510-519.
Little, Richard G. (2003) "Toward More Robust Infrastructure: Observations on Improving the
Resilience and Reliability of Critical Systems." Lecture, System Sciences. Proceedings of
the 36th Annual Hawaii International Conference on, Big Island, Hawaii.
Litwin, M. S. and Fink, A. (2003). How to assess and interpret survey psychometrics, Sage.
Mahoney, SM and Laskey, KB, 1996, “Representing and combining partially specified CPTs”
Proceedings of the Fifteenth Conference on Uncertainty in Artificial Intelligence 391–400.
Marcot, B. G., Steventon, J. D., Sutherland, G. D., & Mccann, R. K. (2006). Guidelines for
developing and updating Bayesian belief networks applied to ecological modeling and
conservation
McGee, Sibel, Jaime Frittman, Seongjin James Ahn, and Susan Murray. 2016. Implications of
cascading effects for the hyogo framework. International Journal of Disaster Resilience in
the Built Environment 7, (2): 144-157
Min, H.-S. J., W. Beyeler, et. al.. (2007). "Toward modeling and simulation of critical national
infrastructure interdependencies." Iie Transactions 39(1): 57-71.
Netica v5.15, http://www.norsys.com/index.html
91
National Association of County and City Health Officials (NACCHO), (2014) Cyber Attack on U.S.
Hospital Group Highlights Vulnerability of Critical Infrastructure
http://nacchopreparedness.org/
National Association of County and City Health Officials (NACCHO), (2015) The Role of Local
Public Health in Healthcare Critical Infrastructure Protection
http://nacchopreparedness.org/
National Institute of Standards and Technologies (NIST), (2014) ) Framework for Improving Critical
Infrastructure Cybersecurity
National Infrastructure Protection Plan (2013) http://www.dhs.gov/publication/nipp-2013-partnering-
critical-infrastructure-security-and-resilience
Nunnally, J. C. (1978). Psychometric theory (2nd ed.). New York, NY: McGraw-Hill.
Ouedraogo, Moussa; Savola, Reijo M.; Mouratidis, Haralambos; Preston, David; Khadraoui,
Djamel and Dubois, Eric. (2013) "Taxonomy of quality metrics for assessing assurance of
security correctness." Software Quality Journal: 67-97.
Ouyang, M. (2014). "Review on modeling and simulation of interdependent critical infrastructure
systems." Reliability Engineering & System Safety 121: 43-60.
Ouyang, M., Dueñas-Osorio, L. (2012). “A three-stage framework resilience analysis framework for
urban infrastructure systems.” Structural Safety 2012; 36: 23–31.
Pearl, Judea. (1988) Probabilistic reasoning in intelligent systems: networks of plausible inference.
San Mateo, Calif.: Morgan Kaufmann Publishers.
Pederson, P., D. Dudenhoeffer, et. al.. (2006). "Critical infrastructure interdependency modeling: a
survey of US and international research."
92
Pettigrew, J., Ryan, J., Salous, K., Mazzuchi, T., & Dc, W. (2009). Decision-Making by Effective
Information Security Managers.
Pfleeger, Shari Lawrence and Cunningham, Robert K., (2010) "Why Measuring Security Is Hard."
IEEE Security & Privacy Magazine: 46-54.
PPD-21 (2013) Critical Infrastructure Security and Resilience, President Barack Obama
Punch, K. F. (2003). Survey research: The basics. London, England: Sage Publications.
Queiroz, C.; Mahmood, A.; Tari, Z., (2013) "A Probabilistic Model to Predict the Survivability of
SCADA Systems," Industrial Informatics, IEEE Transactions on , vol.9, no.4, pp.1975,1985
Radvanovsky, R. S. and A. McDougall (2013). Critical infrastructure: homeland security and
emergency preparedness, CRC Press.
Renooij, S. (2001). "Probability elicitation for belief networks: issues to consider." The
Knowledge Engineering Review 16(03): 255-269.
Riegel, C., Risk Assessment and Critical Infrastructure Protection in Health Care Facilities:
Reducing Social Vulnerability, Retrieved March 10, 2013 From
<http://www.ehs.unu.edu/file/get/3796>
Rinaldi , S. m., Peerenboom J. p. and Kelly, T.k. (2001) "Identifying, understanding, and analyzing
critical infrastructure interdependencies." IEEE Control Systems Magazine: 11-25.
Robert, Benoit (2008). Modelling interdependencies among critical infrastructures. International
journal of critical infrastructures. , 4 (4), p. 392. (ISSN: 1475-3219)
Roberts, Steven (2004) "Tips and Trends for Homeland Security and Critical Infrastructure
Protection," Journal of Homeland Security and Emergency Management: Vol. 1: Iss. 4,
Article 405
93
Ryan, J.J.C.; Ryan, D.J., (2008) "Performance Metrics for Information Security Risk
Management," Security & Privacy, IEEE , vol.6, no.5, pp.38,44.
Ryan, Julie J.c.h., Thomas A. Mazzuchi, Daniel J. Ryan, Juliana Lopez De La Cruz, and & Cooke,
Roger. (2012) "Quantifying information security risks using expert judgment elicitation."
Computers & Operations Research: 774-784.
Ryan, J.j.c.h. (2004) "Information security tools and practices: what works?." IEEE Transactions on
Computers: 1060-1063.
Salkind, N. J. (2009). Exploring research (7th ed.). Upper Saddle River, NJ: Pearson Education.
Sanders, W, (2014). “Quantitative Security Metrics: Unattainable Holy Grail or a Vital
Breakthrough Within Our Reach”, Security & Privacy, IEEE,vol 12 no.2, pp 67-69
Santos, Joost R., Haimes, Yacov Y. and Lian, Chenyang. (2007) "A Framework for Linking
Cybersecurity Metrics to the Modeling of Macroeconomic Interdependencies." Risk
Analysis: 1283-1297.
Santos JR (2006). Inoperability input–output modeling of disruptions to interdependent economic
systems. Systems Engineering pp20–34.
Satumtira G, Dueñas-Osorio L. (2010) Synthesis of modeling and simulation methods on critical
infrastructure interdependencies research. In: Gopalakrishnan K, Peeta S, editors.
Sustainable infrastructure systems: simulation, imaging, and intelligent engineering. New
York: Springer-Verlag.
Sikula, Nicole R., James W. Mancillas, Igor Linkov, and John A. McDonagh. "Risk management is
not enough: a conceptual model for resilience and adaptation-based vulnerability
assessments." Environment Systems & Decisions 35, no. 2 (2015): 219.
SPSS. (2007). SPSS survey tips guide. Retrieved from: http://www.spss.com
94
Symantec 2010 Critical Infrastructure Protection Study Global Results. (2010), (October).
The White House. (2013) "Executive Order -- Improving Critical Infrastructure Cybersecurity."
http://www.whitehouse.gov/the-press-office/2013/02/12/executive-order-improving-critical-
infrastructure-cybersecurity .
Tversky, A., D. Kahneman. 1974. Judgment under uncertainty: Heuristics and biases. Science
185(4157): 1124-1131.
U.S. Government Accountability Office. (2011) "Cybersecurity: Continued Attention Needed to
Protect Our Nation's Critical Infrastructure and Federal Information Systems." GAO-11-
463T
U.S. Government Accountability Office. (2012) "Critical Infrastructure Protection: Cybersecurity
Guidance Is Available, but More Can Be Done to Promote Its Use." GAO-12-92
U.S. Government Accountability Office. (2015) "Critical Infrastructure Protection: Measures Needed
to Assess Agencies’ Promotion of the Cybersecurity Framework. GAO-16-152
U.S. Government Accountability Office. (2017) "Critical Infrastructure Protection: Needs to Better
Measure Cybersecurity Progress.” GAO-16-79
U.S. Government Accountability Office. (2017) "Information Security: DHS Needs to Continue to
Advance Initiatives to Protect Federal Systems." GAO-17-518T
U.S. Government Accountability Office. (2017) "Critical Infrastructure Protection: DHS Risk
Assessments Inform Owner and Operator Protection Efforts and Departmental Strategic
Planning.” GAO-18-62
Vira, C. and Y. Y. Haimes (1983). Multiobjective decision making : theory and methodology. New
York, North Holland.
95
Vugrin, E., D. Warren, et. al.. (2010). A Framework for Assessing the Resilience of Infrastructure
and Economic Systems. Sustainable and Resilient Critical Infrastructure Systems. K.
Gopalakrishnan and S. Peeta, Springer Berlin Heidelberg: 77-116.
Weisberg, H. F. (1977). An introduction to survey research and data analysis. San Francisco, CA:
Freeman & Co.
Wright, P. D., M. J. Liberatore, et. al.. (2006). "A Survey of Operations Research Models and
Applications in Homeland Security." Interfaces 36(6): 514-529.
Written testimony of NPPD Executive Order 13636 and Presidential Policy Directive 21
Integrated Task Force Director Robert Kolasky for a House Committee on Homeland
Security, Subcommittee on Cybersecurity, Infrastructure Protection, and Security
Technologies hearing titled “Oversight of Executive Order 13636 and Development of the
Cybersecurity Framework” (2013)
Zimmerman, R. (2004). Decision-making and the vulnerability of interdependent critical
infrastructure. Systems, Man and Cybernetics, 2004 IEEE International Conference on, IEEE.
Zio E, FerrarioE. (2013) A framework for the system-of-systems analysis of the risk for a safety-
critical plant exposed to external events. Reliability Engineering and System
Safety;114:114–25.
Zio, Enrico (2016) Challenges in the vulnerability and risk analysis of critical infrastructures, In
Reliability Engineering & System Safety, Volume 152, , Pages 137-150, ISSN 0951-8320,
https://doi.org/10.1016/j.ress.2016.02.009.
96
APPENDIX A
Survey on Critical Infrastructure Protection and Resiliency Vulnerability
Impact to Hospital/Patient
A successful Denial of Service (DoS) attack on a Critical Infrastructure (CI) can indirectly have
devastating and irreversible effects to those that depend on its services. Healthcare and public
health facilities rely on various CIs in order to maintain daily operations. A cyber or physical attack
on any interdependent CI (water, power, communications, etc.) can indirectly have a detrimental
and irreversible effect on a patient’s health.
This survey is constructed to identify metrics used by hospitals to protect and/or maintain patient
healthcare and to assess the impact to a patient given a DoS or interruption to power, water or
communications to a hospital. The following questions should be answered from the expert
knowledge of a physician/nurse or administrator caring for a critically/gravely ill patient in Intensive
Care Unit (ICU) totally dependent on a device serviced by power, water or communications. Thank
you in advance for sharing your knowledge/expertise. No personal information will be elicited
or shared in this survey.
Background Information (Anonymous)
1. What is your medical profession? a. Nurse b. Physician c. Administrator
2. How long have you practiced in the medical field? a. Less than 1 year b. 1-5 years c. 6-10 years d. 11-15years e. 16 or more years
3. Do you have experience in the Intensive Care Unit (ICU)? a. Yes b. No
Hospital Metrics
4. What metric is used to trigger backup POWER generator? a. Main source off for greater than 5 minutes b. Main source off for less than 5 minutes c. Unknown
97
d. No metric used 5. What metric is used to trigger backup WATER supply?
a. Main source off or contamination detected in greater than 5 minutes b. Main source off or contamination detected in less than 5 minutes c. Unknown d. No metric used
6. What metric is used to trigger alternate COMMUNICATIONS? a. Main source off for greater than 5 minutes b. Main source off for less than 5 minutes c. Unknown d. No metric used
INSTRUCTIONS: Assessing Impact to Patient
Answers to each of the following questions should add/total to 100%. Answers may be provided in the form of a
check mark or percentages. An example is provided below.
Example: Given a denial of service of POWER to a hospital, resulting in a complete shutdown (No power generator
or main source power), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Very unlikely
(0-20%) Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical ✓
Degraded ✓
No Impact
This answer is interpreted as “given a complete shutdown to power, the likelihood of impact to a patient’s health is very
likely to have a critical impact and 0-20% likely to have a degraded impact”. The likelihood of no impact is
assumed zero, unless answers are provided in percentages. The answer must total 100%.
98
Denial of Service (DoS) - POWER
1. Given a DoS/interruption of POWER to a hospital, resulting in limited power (power generator only), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
2. Given a DoS/interruption of POWER to a hospital, resulting in complete shutdown (No power generator or main source power), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
3. Given a DoS/interruption of POWER to a hospital, resulting in limited power (power generator only and no main source power), what is the likelihood of impact to a patient depending on dialysis (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
4. Given a DoS/interruption of POWER to a hospital, resulting in a complete shutdown (No power generator or main source power), what is the likelihood of impact to a patient depending on dialysis (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
5. Given a DoS/interruption of POWER to a hospital, resulting in limited services (power generator only and no main source power), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
99
6. Given a DoS/interruption of POWER to a hospital, resulting in a complete shutdown (No power generator or main source power), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
Denial of Service (DoS) - WATER
7. Given a DoS/interruption of WATER to a hospital, resulting in limited water supply (backup water supply only), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
8. Given a DoS/interruption of WATER to a hospital, resulting in a complete shutdown (No filtered/uncontaminated water or water from main source), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
9. Given a DoS/interruption of WATER to a hospital, resulting in limited water supply (backup water supply only), what is the likelihood of impact to a patient depending on dialysis (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
10. Given a DoS/interruption of WATER to a hospital, resulting in a complete shutdown ( No filtered/uncontaminated water or water from main source), what is the likelihood of impact to a patient depending on dialysis (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
100
11. Given a DoS/interruption of WATER to a hospital, resulting in limited water supply (backup water supply only), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
12. Given a DoS/interruption of WATER to a hospital, resulting in a complete shutdown ( No filtered/uncontaminated water or water from main source), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
Denial of Service (DoS) - COMMUNICATIONS
13. Given a DoS/interruption of COMMS to a hospital, resulting in limited emergency communications (i.e. ambulance to hospital, patient to nurse/doctor, pharmacy to vendor), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
14. Given a DoS/interruption of COMMS to a hospital, resulting in a complete shutdown of COMMS (No emergency communications (i.e. ambulance to hospital, patient to nurse/doctor, pharmacy to vendor), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
15. Given a DoS/interruption of COMMS to a hospital, resulting in limited emergency communications (i.e. ambulance to hospital, patient to nurse/doctor, pharmacy to vendor), what is the likelihood of impact to a patient depending on dialysis (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
101
Degraded
No Impact
16. Given a DoS/interruption of COMMS to a hospital, resulting in a complete shutdown of COMMS (No emergency communications (i.e. ambulance to hospital, patient to nurse/doctor, pharmacy to vendor), what is the likelihood of impact to a patient depending on dialysis (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
17. Given a DoS/interruption of COMMS to a hospital, resulting in limited emergency communications (i.e. ambulance to hospital, patient to nurse/doctor, pharmacy to vendor), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
18. Given a DoS/interruption of COMMS to a hospital, resulting in a complete shutdown of COMMS (No emergency communications (i.e. ambulance to hospital, patient to nurse/doctor, pharmacy to vendor), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)
Very unlikely (0-20%)
Unlikely (21-40%)
Need more info (41-60%)
Likely (61-80%)
Very Likely (81-100%)
Critical
Degraded
No Impact
102
APPENDIX B
Survey on Patient Impact due to Critical Infrastructure Service Interruption/Denial
1. Which of the following best describe your job function?
Answer Options
Response Percent Response Count
Physician 10.0% 1 Nurse 80.0% 8 Administrator 10.0% 1 answered question 10 skipped question 0
2. How long have you practiced in the medical field?
Answer Options
Response Percent Response Count
Less than 1 year
0.0% 0
1-5 years 20.0% 2 6-10 years 10.0% 1 11-15 years 20.0% 2 16 or more
years 50.0% 5
answered question 10 skipped question 0
3. Do you have experience in the Intensive Care Unit (ICU)?
Answer Options
Response Percent Response Count
Yes 66.7% 6 No 33.3% 3 Other (please specify) 2 answered question 9 skipped question 1
103
4. What metric is used to trigger backup POWER generator?
Answer Options
Response Percent Response Count
Main source off for greater than 5 minutes
0.0% 0
Main source off for less than 5 minutes
50.0% 5
Unknown 50.0% 5 No metric
used 0.0% 0
answered question 10 skipped question 0
5. What metric is used to trigger backup WATER supply?
Answer Options
Response Percent Response Count
Main source off or contamination detected in greater than 5 minutes
10.0% 1
Main source off or contamination detected in less than 5 minutes
20.0% 2
Unknown 70.0% 7 No metric
used 0.0% 0
answered question 10 skipped question 0
104
6. What metric is used to trigger alternate COMMUNICATIONS?
Answer Options
Response Percent Response Count
Main source off for greater than 5 minutes
30.0% 3
Main source off for less than 5 minutes
30.0% 3
Unknown 40.0% 4 No metric
used 0.0% 0
answered question 10 skipped question 0
7. Given a DoS/interruption of POWER to a hospital, resulting in limited power (power generator only), what is the likelihood of impact to a patient depending on cardiac care (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 1 1 2 2 3 9
Degraded 1 2 4 1 0 8
No Impact 3 0 1 0 0 4
answered question 10 skipped question 0
8. Given a DoS/interruption of POWER to a hospital, resulting in complete shutdown (no power generator or main source power), what is the likelihood of impact to a patient depending on cardiac care (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 0 0 3 7 10
Degraded 2 0 1 1 1 5
No Impact 4 0 0 0 0 4
answered question 10 skipped question 0
105
9. Given a DoS/interruption of POWER to a hospital, resulting in limited power (power generator only), what is the likelihood of impact to a patient depending on dialysis (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 2 2 5 1 10
Degraded 1 2 2 1 0 6
No Impact 2 1 2 0 0 5
answered question 10 skipped question 0
10. Given a DoS/interruption of POWER to a hospital, resulting in complete shutdown (no power generator or main source power), what is the likelihood of impact to a patient depending on dialysis (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 0 0 5 5 10
Degraded 1 2 1 1 1 6
No Impact 2 2 0 0 0 4
answered question 10 skipped question 0
11. Given a DoS/interruption of POWER to a hospital, resulting in limited power (power generator only), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 2 2 4 2 10
Degraded 1 1 4 1 0 7
No Impact 2 1 1 0 0 4
answered question 10 skipped question 0
106
12. Given a DoS/interruption of POWER to a hospital, resulting in complete shutdown (no power generator or main source power), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 0 0 2 7 9
Degraded 2 0 2 2 1 7
No Impact 2 1 1 0 0 4
answered question 10 skipped question 0
13. Given a DoS/interruption of WATER to a hospital, resulting in limited water supply (backup water supply only), what is the likelihood of impact to a patient depending on cardiac care (ICU)?
Answer Options
Very Unlikely Unlikely Need More Info
Likely Very
Likely Response
Count
Critical 0 2 1 4 2 9
Degraded 1 3 1 3 0 7
No Impact 2 1 0 1 0 4
answered question 10 skipped question 0
14. Given a DoS/interruption of WATER to a hospital, resulting in a complete shutdown (No filtered/uncontaminated water or water from main source), what is the likelihood of impact to a patient depending on cardiac care (ICU)
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 2 1 2 5 10
Degraded 2 3 0 1 1 7
No Impact 2 0 0 2 0 4
answered question 10 skipped question 0
107
15. Given a DoS/interruption of WATER to a hospital, resulting in limited water supply (backup water supply only), what is the likelihood of impact to a patient depending on dialysis (ICU)?
Answer Options
Very Unlikely Unlikely Need More Info
Likely Very
Likely Response
Count
Critical 0 2 1 4 3 10
Degraded 0 4 1 1 1 7
No Impact 1 1 1 1 0 4
answered question 10 skipped question 0
16. Given a DoS/interruption of WATER to a hospital, resulting in a complete shutdown (No filtered/uncontaminated water or water from main source), what is the likelihood of impact to a patient depending on dialysis (ICU)?
Answer Options
Very Unlikely Unlikely Need More Info
Likely Very
Likely Response
Count
Critical 0 2 0 2 6 10
Degraded 2 2 0 1 1 6
No Impact 2 1 1 1 0 5
answered question 10 skipped question 0
17. Given a DoS/interruption of WATER to a hospital, resulting in limited water supply (backup water supply only), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)?
Answer Options
Very Unlikely Unlikely Need More Info
Likely Very
Likely Response
Count
Critical 0 2 3 3 2 10
Degraded 1 4 1 0 1 7
No Impact 1 1 2 0 0 4
answered question 10 skipped question 0
18. Given a DoS/interruption of WATER to a hospital, resulting in a complete shutdown (No filtered/uncontaminated water or water from main source), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)?
Answer Options
Very Unlikely Unlikely Need More Info
Likely Very
Likely Response
Count
Critical 0 2 0 2 6 10
Degraded 3 3 0 0 1 7
No Impact 1 2 1 0 0 4
answered question 10 skipped question 0
108
19. Given a DoS/interruption of COMMS to a hospital, resulting in limited power (power generator only), what is the likelihood of impact to a patient depending on cardiac care (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 2 1 5 2 10
Degraded 1 4 2 0 0 7
No Impact 0 2 1 1 0 4
answered question 10 skipped question 0
20. Given a DoS/interruption of COMMS to a hospital, resulting in complete shutdown (no power generator or main source power), what is the likelihood of impact to a patient depending on cardiac care (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 1 1 2 6 10
Degraded 2 1 3 0 0 6
No Impact 0 1 4 0 0 5
answered question 10 skipped question 0
21. Given a DoS/interruption of COMMS to a hospital, resulting in limited power (power generator only), what is the likelihood of impact to a patient depending on dialysis (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 3 2 2 3 10
Degraded 1 5 1 0 0 7
No Impact 0 2 1 1 0 4
answered question 10 skipped question 0
109
22. Given a DoS/interruption of COMMS to a hospital, resulting in complete shutdown (no power generator or main source power), what is the likelihood of impact to a patient depending on dialysis (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 3 0 2 5 10
Degraded 2 4 1 0 0 7
No Impact 0 2 1 1 0 4
answered question 10 skipped question 0
23. Given a DoS/interruption of COMMS to a hospital, resulting in limited power (power generator only), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 2 2 3 3 10
Degraded 1 5 0 0 1 7
No Impact 1 2 0 1 0 4
answered question 10 skipped question 0
24. Given a DoS/interruption of COMMS to a hospital, resulting in complete shutdown (no power generator or main source power), what is the likelihood of impact to a patient depending on oxygen/ventilator (ICU)?
Answer Options
Very Unlikely (0- 20%)
Unlikely (21-40%)
Need More Info (41- 60%)
Likely (61- 80%)
Very Likely (81-
100%)
Response Count
Critical 0 1 1 2 6 10
Degraded 2 3 1 0 1 7
No Impact 1 2 1 0 0 4
answered question 10
110
skipped question 0