Date Added: Mar 2012
Cryptographic Hash functions are used to achieve a number of security objectives. In this paper, the authors bring out the importance of hash functions, its various structures, design techniques, attacks and the progressive recent development in this field. Cryptographic techniques mainly encryption & decryptions have been used for centuries to protect military and political secrets and D.Kahn in has given comprehensive study of this history. Throughout this history of cryptology, confidentiality has taken the primary seat and it was believed that if the secrecy is maintained (using symmetric encryption and secret key) then the authentication will automatically be achieved.