A multi-hop pointer forwarding scheme for efficient location update in low-rate wireless mesh networks.

Recently, a pointer forwarding scheme (PFS) was proposed to reduce location update overhead in wireless mesh networks. Using PFS, a location update is replaced with a simple forwarding pointer setup between two neighboring mesh routers (MRs). However, in PFS, if the two MRs are not one hop neighbors, PFS fails to set up a forwarding pointer, thus increasing location update overhead. To improve PFS, we present a multi-hop pointer forwarding scheme (MPFS). MPFS allows forwarding pointers to be constructed over multi-hop at once even if MRs are not one hop neighbor by using logical tree distance constructed during network formation. The tree distance is used to relay forwarding pointer packets over multi-hop links without additional control overhead during forwarding pointer setup and to estimate hop distance between two MRs. By doing so, MPFS improves the probability of success in forwarding pointer setup while ensuring k≤km, resulting in lowering the location update overhead. Also, we analyze pointer forwarding success probability and average chain length and discuss why MPFS is suitable for resource-constrained LRWMNs. Using ns-2, we show that MPFS significantly reduces the number of location update events, location update delay and signaling overhead, and packet losses during location updates. With real-world implementation, we also confirm feasibility of MPFS.