Efficient Role Assignment Scheme for Multichannel Wireless Mesh Networks

a wireless mesh network (WMN) is cost-effective access network architecture. The performance of multi-hop communication quickly reduces as the number of hops becomes larger. Nassiri et al. proposed a Molecular MAC protocol for autonomic assignment and use of multiple channels to improve network performance. In the Molecular MAC protocol, each node forms a shortest path-spanning tree to a gateway node linked to a wired Internet. After a tree is formed, the nodes with an even-numbered depth and an odd-numbered depth are assigned with the roles of a nucleus and an electron, respectively. After such roles are assigned, each nucleus selects an idle channel. However, this protocol has the following drawback; since the nodes with an even-numbered depth are assigned with the role of a nucleus, there are many nuclei in the topology. The number of assigned channels tends to increase, since each nucleus selects an idle channel that is not currently being occupied by its neighboring nuclei. In wireless communications networks, channels are very important resources. Thus, it is necessary to assign the minimum number of channels as little as possible. To do so, this paper proposes an efficient role assignment scheme, which can reduce the number of assigned channels by reducing the number of nodes assigned as nuclei and preventing nodes within the transmission range of each other from becoming nuclei. Based on various simulation results, the proposed scheme was verified.