Enhancing the Security of MANETs using Hash Algorithms

Hash functions are used in information security applications for the generation and verification of digital signatures, key derivation, and pseudorandom bit generation. Hash algorithms are secure because, for a given algorithm, it is computationally infeasible to find a message that corresponds to a given message digest, or to find two different messages that produce the same message digest. Any change to a message will result in a different message digest with a very high probability. This will result in a verification failure when the secure hash algorithm is used with a digital signature algorithm or a keyed-hash message authentication algorithm. In our work, first we implemented the Zone Routing Protocol (ZRP), a hybrid MANET protocol is being implemented in Network Simulator 2 (NS2) and hashing algorithm, keyed-Hash Message Authentication Code - Secure Hashing Algorithm 512 (HMAC-SHA512) is implemented for the Authentication and Data Integrity of the information being sent. In addition to that a Trust-Based system is formulated for preventing the Denial-of-Services (DoS) Attacks. The first part of this paper introduces the HMAC-SHA512 for ensuring that the data packets are received by the destination only and in its original form but at the expense of the increased processing time at the source and the destination. The second part uses the Trust-Based system with those nodes that act maliciously being broadcasted in the network and isolated to render a higher throughput and packet delivery fraction but at the expense of the increased end to end delay.