Rendezvous in Dynamic Spectrum Wireless Networks

Establishing communications in a dynamic spectrum access (DSA) network requires the communicating parties to “rendezvous” before transmitting their data packets. Frequency hopping (FH) provides an effective method for rendezvousing without relying on a predetermined control channel. Previous FH-based rendezvous designs do not account for fast primary user (PU) dynamics, which results in extremely long rendezvous delay. Furthermore, these designs mainly target pairwise rendezvous, and do not intrinsically support multicast rendezvous. Intrinsic multicast rendezvous is required to consistently update the secret information in a multicast group. In this paper, we first design a grid-quorum-based FH algorithm, called NGQFH, for pairwise rendezvous. NGQFH can achieve efficient rendezvous under fast PU dynamics. It is also robust against insider attacks, such as node compromise. Using the uniform k-arbiter and Chinese Remainder Theorem quorum systems, we then propose three multicast rendezvous algorithms, which provide different tradeoffs between the time-to-rendezvous and robustness to node compromise. Our rendezvous algorithms are tailored for asynchronous and heterogeneous DSA networks. To account for fast PU dynamics, we develop an algorithm for adapting the proposed FH designs on the fly. This adaptation is done through efficient mechanisms for channel sensing, assignment, and quorum selection. Our simulations validate the fast rendezvous capability of the proposed algorithms, their PU detection accuracy, and their robustness to insider attacks.