Network Access Control for Mobile Ad-Hoc Networks

摘要

In this paper, we propose to enforce network access control in Mobile Ad Hoc Networks (MANETs) using cryptographic techniques. In the proposed approach, packets are authenticated by means of a network-wide symmetric (session) key. Because nodes are mobile and communication paths may change rapidly, timely distribution of new session keys is challenging (particularly if keys change frequently). Nodes wishing to communicate may therefore hold different session keys, which must somehow be synchronized. We present a fully distributed key synchronization method based on stateless group key distribution, and localized packet retransmission. If nodes A and B wish to communicate securely over a path P, all nodes on this path must synchronize keys with their immediately adjacent neighbors in the path. Any node which is unable to synchronize keys will not be allowed to forward packets. Simulations and a functioning prototype demonstrate the proposed system is practical and effective.