LOCHA: A Light-weight One-way Cryptographic Hash Algorithm for Wireless Sensor Network

Cryptographic hash functions are used to protect the authenticity of information. Some of the most popular and commonly used cryptographic hash algorithms are MD5, SHA1, RIPEMD. These hash algorithms are used in a wide variety of security applications e.g. securing node/message in traditional networks. However, the commonly used hash algorithms require huge computational overhead which is not affordable by applications in energy-starved network e.g. wireless sensor network (WSN). In these applications the major constraints are communication, computation and storage overheads; out of which communication and computation overheads consume high energy. Keeping this fact in mind, in this paper, a light-weight, one-way, cryptographic hash algorithm is developed with a target to produce a hash-digest with fixed and relatively small length for such an energy-starved wireless network. The primary focus is making the algorithm light-weight so that upon using it in application of network like WSN, the nodes can successfully run the algorithm with low energy. We claim the algorithm fulfils all the basic properties such as preimage resistance, collision resistance of a one-way unkeyed hash function. Finally the comparative usability of the hash algorithm in the said application domain is worked out and that shows the dominance of our scheme over two of the state-of-the-art hashing schemes.