Secure Hash Algorithm (SHA) was designed by the National Security Agency (NSA) and published by National Institute of Standards and Technology (NIST) as the Federal Information Processing Standard (FIPS 180) in 1993, SHA-1 is the update to the SHA on the basis of which the remaining SHA series of SHA-224, SHA-256, SHA-384 and SHA-512 are designed, numbers in the algorithm denotes the hash value they generate.

The basic principle for designing of SHA is based on MD4 hash function which closely relates to MD4. Five models of SHA are designed  known as SHA-1, SHA-224, SHA-256, SHA-384 and SHA-512 the basic model of SHA-1 generates a message digest of 160 bits where as newer versions generates higher hash values using the same arithmetic calculations.

Hashed Message Authentication Code (HMAC)

            This is similar to Cryptographic hash function, but due to the insufficient security provided by the cryptographic hash functions and Mac’s, the process of hashing the secret key along with the message provides the authentication along with the integrity without chance of eavesdropping on secret key. In the modern network communication, the above proposed hashing algorithms are found to be insufficient to the cryptographers for the different kinds of private and confidential data and software’s that are been transferred using networks.

This Project Paper is written & submitted by Deepak V.