OSPF Over Multi-Hop AD HoC Wireless Communications

Abstract

Efficient OSPF (Open Shortest Path First) operation on multi-hop ad hoc wireless networks has become desirable, as wireless community mesh networks and vehicular networks emerge using OLSR (Optimized Link State Routing), a link state MANET routing protocol similar to OSPF in many aspects. OSPF is already extensively deployed and well known in wired IP networks, and could provide simple, seamless unification of wired and wireless IP networking routing-wise, if extended to operate efficiently on ad hoc networks. The IETF has thus proposed three different MANET extensions to the OSPF protocol, allowing heterogeneous networks encompassing both wired and wireless routers, which may self-organize as multi-hop wireless subnetworks, and be mobile. Two of these extensions are based on techniques derived from multi-point relaying (MPR). In the following, we compare and analyze these two extensions and we propose a unique, merged approach which out-performs the existing extensions.