Cryptography and Network Security Essay
HISTORY & TYPES OF CRYPTOGRAPHY The history of cryptography is outstanding. Cryptography has …show more content…
• Data Encryption Standard (DES) – Most common SKC method used today. DES was originally designed by IBM in the 1970's. It was later adopted by the National Institute for Standards and Technology in 1977 for commercial and unclassified government applications.
• Advanced Encryption Standard (AES) – AES uses an SKC method using a block cipher designed by Belgian cryptographers. The algorithm uses a variable block length and key length. It allows any combination of keys lengths of 128, 192, or 256 bits and blocks of length 128, 192, or 256 bits.
• CAST-128/256 – Is a DES like substitution-permutation algorithm. It employs a 128-bit key operating on a 64-bit block. CAST-256 is an extension which uses a 128-bit block size and a variable length key. CAST-256 was one of the Round 1 algorithms in the AES process.
PUBLIC KEY CRYPTOGRAPH (PKC) – Uses one key for encryption and another for decryption
Public Key Cryptography has been claimed to be the most significant new cryptographic development. PKC depends on the existence of mathematical functions that are easy to compute but their inverse function required being more difficult to compute. PKC uses two keys that are mathematically related. However, the knowledge of one of the keys does not allow someone to easily determine