A class of key-node indexed hash chains based key predistribution (KPS): Signed weighted graphs

Abstract

Key management solutions are cornerstone requirements for any security service. Due to resource limitations, public key cryptographic (PKC) solutions are unsuitable for IoT devices like sensors of WSN. Consequently we opt for key predistribution schemes (KPS) to preload lightweight symmetric cryptographic keys and later establish them. KPS are designed over random and/or combinatorial graphs and requires several devices to share individual keys (conventionally r many). This causes a dip in the resultant system’s resilience. Cichoń et al. [10] introduces a technique that involve recursive use of a one-way function to distinguish each key’s cycle and improve the given system’s resilience. Bechkit et al. [2,3] considers a cryptographic hash function to form their hash chains (KPS), i.e., HC(x) for a given KPS x. They construct hash chains according to node identifiers (ids) and consider modulo n,(n∈Z+) to reduce hash chains. This paper uses signed weighted graph (SWG) to conceal node ids in the key sharing graph of the underlying KPS x during short-lived key establishment phase (KEP). The concealment of information permits distinct indexing of each sensor according their position in the cycles of preloaded keys. Resultant system remains distributed with improved resilience and is independent of other parameters. In this way, a new class of KPS, named as key-node indexed hash chains (KPS), i.e., KNIHC(x) for the selected KPS x is proposed. It eliminates smart attack (SA). Moreover being fully connected (due to choice of underlying KPS), the proposed system supports mobility.