Introduction:- Goals of Security, types of attacks, services and mechanism, different techniques. Mathematics involved – integer arithmetic, modular arithmetic, matrices, linear congruence, algebraic structures,GF(2n) fields. Symmetric key ciphers – Kerckhoff’s principle, substituition ciphers, transposition ciphers, stream and block ciphers,modern block ciphers, modern stream ciphers, DES structure and analysis, multiple DES, security, AES- transformations, key expansion, ciphers, analysis.

Asymetric key cryptography – RSA cryptosystem, RABIN cryptosystem, ELGAMAL cryptosystem, elliptic curve cryptosystem. Message integrity, Random oracle model, message authentication, hash functions, digital signature, entity authentication, Key management.

Network security: At application layer – Email, PGP, S/MIME. At transport layer – SSL architecture, handshake protocol, changecipherspec protocol, Alert protocol, Record protocol, SSL message format, Transport layer security. At network layer – modes, security protocols, security associations, security policy, Internet key exchange, ISAKMP.

1. Behrouz A. Forouzan, “Cryptography and Network Security”, Tata McGraw-Hill Publishing.
2. Manuel Mogollon, “Cryptography and Security Services – Mechanisms and Applications”, Cybertech Publishing.
3. William R. Cheswick, Steven M. Bellovin, Aviel D. Rubin, “Firewalls and Internet Security”, Addison-Wesley.