Key Generation for Wireless Sensor Networks Using Symmetric Balanced Incomplete Block Design

Abstract

Wireless sensor networks consist of many tiny sensor nodes deployed at a high density over region, requiring surveillance and monitoring. The sensor nodes typically consist of one or more sensing elements, battery, low powered radio transmitter/receiver, microprocessor, and limited memory. Sensor networks deployed in a hostile environment are prone to malicious attacks like eavesdropping, masquerading, traffic analysis, et cetera. Hence, security is more important in sensor networks than in traditional networks. An important challenge in sensor network security is the design of effective bootstrapping protocols for the nodes, which are pre-initialized with some secret information and have had no prior direct contact with each other. Each node has a set of keys, called a key chain, rather than a single shared key. The keys in the key chain are picked randomly from a key pool. Two neighboring nodes either share a common key or should be able to establish a key path such that every pair in the path shares a key. One problem in such a solution is to select a proper key chain so that the network remains connected with a high probability.