Handoff And Routing Strategies In 802.11s Based Wireless Mesh Network

With the proliferation of Internet,Wireless Mesh Networks(WMNs)have become a practical wireless solution for providing ubiquitous broadband Internet access services.WMNs inherit various useful characteristics including low-cost deployment,robustness and flexibility from both the ad-hoc networking paradigm and the traditional wired infrastructure paradigm.Besides,compared to the envisioned single-hop access methodology of traditional wireless networks,WMNs can significantly improve the network coverage through multi-hop relaying.Hence,they are undergoing rapid progress and inspiring numerous applications.To guarantee the proper operation of such network,it is imperative to design an efficient handoff scheme.Handoff is seen as a necessary component of mobility management,which provides service continuity whenever users cross the coverage boarder of their serving access points.However,existing handoff strategy does not take into account the nontrivial multi-hop transmission of signaling message.Such overhead inevitably results in low network throughput.To this end,we resort to the clustering concept to explicitly model the network handoff procedure.A novel analytical model is proposed to measure the signaling overhead induced by both the inter-cluster and intra-cluster handoff process.Based on this,we investigate the overhead minimization cluster formation problem and find its optimal solution.On the other hand,routing lays the foundation for multi-hop relaying in WMNs.It mainly takes charge of end-to-end transmission path selection from the source to the destination.Nevertheless,existing sustainable routing schemes for energy harvesting WMNs suffer significantly from low spectral efficiency(SE)performance,either because the selected path goes through links with poor quality or the route stretches too long so as to bypass nodes with low residual energy.This will inevitably lead to low SE(i.e.,end-to-end attainable rate),and consequently underutilization of the scarce bandwidth resource.To cope with the above issue,we take SE into consideration and formulate the sustainable routing problem with stringent SE guarantee as an integer nonlinear programming problem.In order to obtain its optimal solution,we utilize the divide-and-conquer strategy to decompose the problem.In addition,an optimal shortest path based sustainable routing(SPSR)algorithm is proposed to solve the problem with polynomial-time complexity.