Distributed channel assignment in Wireless Mesh Networks with guaranteed connectivity

Using multiple radios/channels in wireless mesh networks (WMNs) can significantly boost the throughput of the network and brings broadband wireless access to more users with reduced cost. However, this requires careful assignment of channels to each radio so that interference due to parallel communications can be minimized and the network is not partitioned. We propose a distributed channel assignment protocol for WMNs to maximize the total number of non-interfering concurrent active links and guarantee the network connectivity. The motivation for maximizing the number of links is to give as much leeway to the routing subsystem as possible. The problem is modeled as a list coloring problem where each channel corresponds to a color. The main idea is to determine the minimum degree spanning tree (MDST) of the network for providing more parallel transmissions and guaranteeing connectivity. The links that are not part of the MDST are assigned channels based on a 5-way handshake protocol to resolve arising conflicting requests in the distributed approach. We validate the performance by comparing our approach to a greedy channel assignment that does not guarantee connectivity.