Farzaneh Vosoughi Rahbari - Young Researchers and Elite Club, Sirjan Branch, Islamic Azad University, Sirjan, Iran
Hamid Mirvazir - Assistant Professor of computer Engineering Department of computer Engineering, Shahid BahounarUniversity of Kerman, Kerman, Iran

Given the growing demand for digital data security, the most importantmatter for specialists is the way of protection and data encryption.Encrypting the hashed message authentication code (HMAC) includedhash function and an encryption secured key that is one of the mostuseful and important tools in credit issues, cryptographic and use ofhash functions that can be used to verify the data and messageauthentication simultaneously. Due to the attacks on hash functionssuch as MD5 and SHA-1, nowadays the functions are not secure todesign HMAC. This article deals with the implementation of HMAC byusing the new hash functions Keccak, Blake and Grostl in the 256-bitversion. The Implementation of HMAC, Keccak function comparedwith other hash functions show that there is a relative improvement intesting the avalanche effect, balance and distortion parameters andResistance to collision attacks. Likewise, this implementation needs lesstime so that the function would be more suitable for implementation ofHMAC.

hash functions, authentication code, the hashed message authentication code (HMAC), distortion parameters