Joint Synchronization, Routing and Energy Saving in Multi-hop Hybrid Networks

Multi-hop hybrid networks can help providing both high bandwidth and broad coverage for wireless data networks. We focus on CSMA/CA-based networks and take IEEE 802.11 as a concrete example. We show that the three fundamental operations of synchronization, routing and energy saving can be implemented in an integrated way. Our integrated solution is based on the periodic computation of a broadcast tree among the nodes reporting to the same Access Point, starting from the Access Point itself. We use the nodes that are tree vertices as relays for both data and control packets. We propose a distributed neighbor discovery protocol and a simple centralized algorithm for computing the broadcast tree. Our analysis and simulation results show that the proposed solution has low protocol overhead in terms of message passing and execution time, and performs well even if nodes are mobile.