The purpose of a hash function is to produce a “fingerprint” of a message or data for authentication. The strength of the Hash code against brute-force attacks depends on the length of the hash code produced by the algorithm. Constructing the Message Authentication Codes (MAC) from Cryptographic hash functions (SHA-256) gives faster execution in software than symmetric block ciphers like Data Encryption Standard (DES) and also the library code for cryptographic hash functions are widely available.
Here we implemented the HMAC-SHA 256 Algorithm for the message authentication and Data Integrity. This algorithm is introduced in hybrid routing protocol for Mobile network environment and the performance of the protocol is analyzed by calculating throughput, packet delivery ration and end-to-end delays of the network The simulation is carried out using Network Simulator 2 (NS2). We observed that there is an improvement in throughput and packet delivery ratio at the cost of more processing time.