Unit - I : Introduction Security trends - Legal, Ethical and Professional Aspects of Security, Need for Security at Multiple levels, Security Policies - Model of network security - Security attacks, services and mechanisms - OSI security architecture - Classical encryption techniques : substitution techniques, transposition techniques, steganography - Foundations of modern cryptography : perfect security - information theory - product cryptosystem - cryptanalysis. (Chapter - 1) UNIT - II : Symmetric Key Cryptography Mathematics of Symmetric Key Cryptography : Algebraic structures - Modular arithmetic - arithmetic – Euclid’s algorithm - Congruence and matrices - Groups, Rings, Fields - Finite fields - Symmetric Key Ciphers : SDES . Block cipher Principles of DES - Strength of DES - Differential and linear cryptanalysis - Block cipher design principles - Block cipher mode of operation - Evaluation criteria for AES - Advanced Encryption Standard - RC4, Key distribution. (Chapter - 2) UNIT - III : Public Key Cryptography Mathematics of Symmetric Key Cryptography : Primes - Primality Testing - Factorization - Euler’s totient function, Fermat‘s and Euler‘s Theorem - Chinese Remainder Theorem - Exponentiation and logarithm - Asymmetric Key Ciphers : RSA cryptosystem - Key distribution - Key management - Diffie Hellman key exchange - ElGamal cryptosystem - Elliptic curve arithmetic - Elliptic curve cryptography. (Chapter - 3) UNIT - IV : Message Authentication and Integrity Authentication requirement - Authentication function - MAC - Hash function - Security of hash function and MAC - SHA - Digital signature and authentication protocols - DSS - Entity Authentication : Biometrics, Passwords, Challenge Response protocols - Authentication applications - Kerberos, X.509. (Chapter - 4) UNIT – V : Security Practice and System Security Electronic Mail security - PGP, S/MIME - IP security - Web Security - System Security : Intruders - Malicious software - viruses - Firewalls. (Chapter - 5)
