Why?
Cryptography underpins secure communication, authentication and data protection. Knowing how the algorithms work, and where software breaks, lets you reason about real security rather than treat it as a black box.
What?
A technical follow-up to Data Security: security concepts, block ciphers and DES, 3DES and block cipher modes, AES, public-key cryptography and RSA, hash functions, MACs and digital signatures, secure communication protocols, buffer overflow, and penetration testing.
Curriculum:
Computer and Network Security Concepts
Security goals, attacks, services and mechanisms, and the overall security landscape.
Block Ciphers and DES
Symmetric encryption, the structure of block ciphers and the steps of the Data Encryption Standard.
AES
The Advanced Encryption Standard: structure, rounds, S-boxes and a worked implementation example.
3DES and Block Cipher Modes
Triple DES and modes of operation such as ECB, CBC, CFB, OFB and CTR.
Public-Key Cryptography and RSA
Asymmetric cryptography, key exchange, and the RSA algorithm with its number theory.
Hash Functions, MACs and Digital Signatures
Cryptographic hash functions, message authentication codes, digital signatures and the Digital Signature Standard (DSS).
Protocols for Secure Communications
How cryptographic tools combine into protocols such as TLS/SSL, IPsec and secure email.
Software Security and Buffer Overflow
How buffer overflow attacks work and how code and systems defend against them.
Penetration Testing
Methodology and tools for ethical hacking and testing a system's defences.
Notes
Math heavy, with worked algorithm examples (DES, AES tables) and exercise sets for most chapters. Practice the exercises.