Discussion 8
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Week10Lecture.pptxFundamentals of Cryptography Week 10
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Week 10 Agenda
Week 10 Overview
Reading
Discussion Question
Quiz
Public Key Infrastructure (PKI)
Week 11 Pre-view
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Discussion Question 8
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Peer Response(s): Peer Response(s) are due by Sunday, November 5th (11:59:59pm ET)
Primary Task Response:
Primary Task Response:
Primary Response: Primary Discussion Response is due by Wednesday, November 1st (11:59:59pm Eastern Time Zone (ET))
Public Key Infrastructure
Public Key Infrastructure (PKI) is a combination of software, hardware, and policies used to secure communications over an insecure medium. PKI can also provide a system that allows validation of credentials, known as digital signatures, that are the cornerstone of the system.
Please explain the PKI process and identify the PKI structure to include the major roles.
As it relates to certificates in the real world, what is X.509 and why is it important?
What are some issues that we should be aware of when building and using PKI Infrastructure?
Discussion Question 7
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- Read the responses from your peers and offer a constructive critique or additional information that adds substantively to the discussions.
Peer Response
- Remember, a response that simply states that their post was good or that you liked it is not considered substantive and will not earn credit.
- You should contribute to the learning via your posts and responses.
- Be sure to acknowledge any outside sources you use.
Week 10 Overview
Reading – Chapter 7 in our text
Discussion Question 7 – Public Key Infrastructure
Quiz 6
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What is PKI?
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Key Management
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Usage Control
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Storage
Recovery
Escrow
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Zeroization
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Creation
Change and Expiry
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Distribution
Creation
Automated key generation
Truly random
Suitable length
Key encrypting keys
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Key Usage Control
Management has a vested interest in what activities or content may be hidden in cryptographically protected communications or files
They may create a policy that allows management to audit or decrypt encrypted data at their discretion
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Key Change and Expiry
In any environment, plans should be made to update keys periodically
Generating symmetric keys is easy, but delivering them is expensive since you will be delivering [N*(N-1)]/2 keys to N users
Expiry
Expiry ensures that a key is never overused
Expiry based upon:
Amount of traffic
Amount of traffic over time
Time-in-use
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Distribution
Out of band
Public key encryption
Secret key construction
Secret key delivery
Key Distribution Centers (KDC)
Certificates
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Storage
Trusted hardware
Smartcards
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Recovery
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Split knowledge
Multi-party key recovery (MPR)
Escrow
A process, mechanism, or entity that can recover a lost or destroyed cryptographic key
Key escrow systems are typically made up of three components:
A user component that handles the generation and use of cryptographic keys
An escrow component that saves the keys
A recovery component that provides the restoration services
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Law Enforcement Issues
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Commonly available commercial and open source encryption can hinder law enforcement in executing investigations
Many countries have laws concerning the import, export, and use of encryption (Wassenaar Arrangement)
Key Zeroization
Erasure of keys to prevent disclosure — especially when equipment is to be discarded or if stolen
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Public Key Infrastructure (PKI)
Public Key Infrastructure binds a people/entities to their public keys
Public keys are published and certified by digital signatures
Cross-Certification (Xcert)
Certificate Revocation Lists (CRLs)
X.509 standard
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Public Key Infrastructure (PKI)
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Certification
Trust and Trust Models
Certification establishes trustworthiness of public keys
Certification Authority (CA)
Certificate Policy (CP)
Certificate Practice Statement (CPS)
Registration Authority (RA)
Validate Certification Path
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Applications and Encryption Issues
Third-party CAs:
Allow business partners to trust (to some level) your public key certificates
Have a mutual trust in the CA (e.g., VeriSign)
If we choose to run our own CA, will anyone trust us?
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Week 11 Overview
Residency Weekend!!!!
Nov 10 – 12
Northern Kentucky Campus
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Questions?
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