In conventional Wireless Mesh Networks (WMNs), multihop relays are performed in the backbone comprising of interconnected Mesh Routers (MRs) and this causes capacity degradation.
We propose hybrid WMN architecture that the backbone is able to utilize random connections to Access Points (APs) of Wireless Local Area Network (WLAN). In such a proposed hierarchal architecture, capacity enhancement can be achieved by letting the traffic take advantage of the wired connections through APs.
Theoretical analysis has been conducted for the asymptotic capacity of three-tier hybrid WMN, where per-MR capacity in the backbone is first derived and per-MC capacity is then obtained. Besides related to the number of R cells as a conventional WMN, the analytical results reveal that the asymptotic capacity of a hybrid WMN is also strongly affected by the number of cells having AP connections, the ratio of access link bandwidth to backbone link bandwidth, etc.
MR configuration of the network can drastically improve the network capacity in our proposed network architecture. It also shows that the traffic balance among the MRs with AP access is very important to have a tighter asymptotic capacity bound. The results and conclusions justify the perspective of having such a hybrid WMN utilizing widely deployed WLANs. Capacity of Hybrid Wireless Mesh Networks with Random APs
The Mesh routers (MRs) play an essential role in a WMN, which provides service for MCs on one hand; forward data packets via wireless link to neighboring MRs on the other hand. Interconnected MRs form the backbone of a WMN, where several special MRs connecting to the
Internet with wired cables are called Internet Gateways (IGWs). By taking disadvantage of wireless Multihop forwarding deployment of MRs poses much less constraints as they can be deployed on electric poles or house rooftop. Such deployment feasibility enables a WMN to provide low cost metro-scale coverage for MCs’ access. The major challenge in a WMN is the capacity degradation problem caused by the interference on a single or multiple routing paths during Multihop transmission. Although the network architecture of any WMN is different from an ad hoc network, the asymptotic capacity bound derived by the analytical work in [3] is still valid for a WMN backbone
The designed to have information about the complete network topology so as to perform routing functions without involving the IGW capacity is constrained by the IGWs and the capacity may be worse than that of ad hoc routing in the backbone. Having the whole network information at the MRs may lead to excessive overhead and may not facilitate easy management of the clustering approach. The backbone of a WMN consists of MRs and IGWs, where the MRs and the IGWs are wireless interconnected to each other and provide service to the MCs. Multiple IGWs divide a WMN into several clusters such that each one is led by an IGW.
We investigate such an IGW cluster. MRs in the cluster is homogeneous that have the same backbone and access link transmission region. Due to interference among neighboring MRs, they have to share wireless resources in the frequency domain and/or time domain. The network is modeled as shown in Fig. 4, where grid deployed MRs are indicated by blue circles, the IGW is indicated by red rectangles, randomly distributed MCs are indicated by green dots, and APs are indicated by dark triangles. The three tiers of a hybrid WMN are: MCs in the first tier connect to the MRs in the second tier.