Abstract:
Multi-hop wireless connectivity, frequently changing network topology and limited bandwidth are main characteristics of mobile ad hoc networks, which pose lots of challenges to routing protocols of such networks. If multi-hop route fails, the routing protocol should maintain it. The previous route repair mechanism causes high control overhead and long packet delay. The problem worsens when mobility is high and many real-time applications do not tolerate such long delays. In broken route, only nodes near the broken links may need to be substituted and the rest of nodes can be retained on the route. In this paper, a new idea about local route repair which limits the repair vicinity of the broken links is proposed to decrease the reaction time of route breakage and the overhead of route maintenance. This is desirable to solve the problem with the least cost in terms of both bandwidth and time. Furthermore, the approach can repair failure links without taking into account of their relative position on the whole path. It improves obviously the ability of dealing with failure links and scalability properties of ad hoc networks. Simulations show that the improved routing protocol results in significant performance improvement, such as packet delivery ratio and end-to-end packet delay.