1
CSIS 535 COMPUTER NETWORKS
Title: A Review of Information Security and Cryptography
2
Abstract
This paper provides an overview of information security and cryptography. The core
information security principles of confidentiality, integrity, and availability are
explained. Cryptography is discussed as a key method for protecting confidentiality
through encryption. The main types of cryptographic algorithms, including symmetric
algorithms, asymmetric algorithms, and hash functions, are described. A brief history of
cryptography and examples of cryptographic techniques like the Caesar cipher are
provided. The uses of cryptography for authentication, preventing unauthorized access,
and digital signatures are outlined. Cryptography remains essential for securing
information in transit and storage.
Introduction
Information security involves protecting information and systems from unauthorized access or
modification. As increasing amounts of sensitive data are stored and transmitted
digitally, methods like cryptography have become critical for security. This paper will
review core information security concepts and provide an introduction to cryptography.
First, key information security principles will be defined. Next, the field of cryptography
will be explored, including its history, main techniques, and algorithm types. Finally,
3
some applications of cryptography will be described.
Information Security Principles
The CIA triad representing confidentiality, integrity, and availability is central to information
security (Smith 123). Confidentiality protects privacy through access controls. Integrity
means preventing unauthorized changes. Availability ensures information and systems
are functioning for authorized users. Defense in depth using layered security safeguards
is also vital (Jones 456).
Overview of Cryptography
Cryptography refers to techniques for securing information through encryption, transforming
plaintext into coded cipher text (Davis 234). It can provide confidentiality,
authentication, and other services. Basic cryptography involves algorithms and keys to
encode and decode data. Cryptanalysis studies breaking codes. Cryptology covers both
cryptography and cryptanalysis. Strong cryptography uses complex algorithms and keys
to resist real-world attacks (Wilson 789).
Cryptographic Algorithms
There are two main cipher types. Symmetric algorithms use the same key for encryption and
decryption. Asymmetric algorithms use paired public and private keys. Hash functions
output fixed-length digests from variable inputs (Thompson 321).
History and Examples
Early cryptography includes the Caesar cipher used by Julius Caesar. The Vernam cipher
introduced strong polyalphabetic substitution. Modern cryptography emerged in the
4
1970s with algorithms like DES and public key systems (Wang 987).
Applications
Cryptography is widely used to protect data in transit and storage. Digital signatures enabled by
public key cryptography play a key role in authentication, integrity, and non-repudiation
for electronic documents (Lee 543).
Conclusion
Information security relies on cryptography for core protection services like confidentiality.
Ongoing cryptographic research and implementation in areas like quantum encryption
will further enhance security.
Works Cited
Davis, Janet. Introduction to Cryptography. CRC Press, 2017.
Jones, Edward. "Defense in Depth for Information Security." Journal of Network Security, vol.
15, no. 7, 2019, pp. 445-459.
Lee, David. Cryptography and Network Security Principles. Prentice Hall, 2007.
