Data Dependent Keying for Wireless Networks

The failure of the 802.11 WEP security specifications to provide any reasonable level of security has come under sharp criticism recently. In this paper we propose a novel scheme for providing security in both a base station based, as well as an ad hoc network environment. Our proposed scheme uses data exchanged between communicating peers to evolve per-packet keys. In addition to the concept of data dependent keying (DDK), we include other well-known security primitives such as SHA-1 based HMAC and RC4 encryption to provide a complete security solution for wireless networks. We argue that our scheme provides an adequate security/overhead tradeoff, and can be easily implemented on current hardware platforms. In addition, the low overhead characteristic as well as the use of symmetric cryptographic functions makes the scheme an attractive option for sensor networks, where energy efficiency is a primary objective.