Key agreement for wireless networks in the presence of active adversaries

In this work we consider key agreement in a distributed wireless network in which adversarial nodes may exist in the network. Two practical scenarios are studied, i.e., path-key establishment and key pool bootstrapping. For both scenarios, previous work mainly focuses on preventing adversarial eavesdropping attacks. When the adversarial nodes can both eavesdrop and change the packets in the network, we show that an optimal scheme (in terms of error correction capability) can be obtained by using techniques from the literature of network error correction codes. In particular, for the path-key establishment problem, which has a particular topological structure, we propose a lightweight scheme with lower error probability and computational complexity than existing network error correction codes. For the key pool bootstrapping scenario, we show a connection with multisource network error correction coding, and show that network coding is necessary for optimal resilience against adversarial attacks.