A computationally efficient HMAC-based authentication scheme for network coding

One of the major security threats that plague network coding are pollution attacks. Therefore, the ability to authenticate the contents of received packets is a vital requirement of all network coding authentication schemes. One of the most famous cryptographic approaches used to mitigate data and tag pollution in network coding are homomorphic message authentication codes (HMACS). In this approach, authentication is achieved by appending one or more HMAC tag vectors and in some cases a homomorphic cryptographic signature to the packet payload. Two major concerns arise when designing authentication schemes for network coding. These are the costs associated with the communication and computational overheads. These two factors determine the efficiency and practicality of the scheme. Unfortunately, in most cases, lowering one of the costs results in an increase in the other. In this paper we propose an efficient data and tag pollution immune authentication scheme based on HMACs and a homomorphic cryptographic signature. In our evaluation of the performance of the proposed scheme we compared it with three other similar state of the art schemes. The result of our evaluation showed that the proposed scheme incurs a computational overhead that is up to 64–97% lower at the source and non-source nodes. The proposed scheme also fairs well with respect to communication overhead where it is only outperformed by one of the three schemes. This difference however is minute (one symbol) and is greatly outweighed by the proposed schemes lower computational overhead.