Motion vector routing protocol: A position based routing protocol for mobile ad hoc networks.

摘要

A Mobile Ad Hoc Network (MANET) consists of mobile nodes, equipped with wireless communications devices, which form a communications network without fixed network infrastructure or topology. The MANET is typically characterized by: limited bandwidth; limited radio range; high mobility; and susceptibility to impairments that degrade the signal to noise ratio and bit error rates. These characteristics pose challenges to the MANET routing protocols. In addition to these characteristics, we have found that the mobility pattern of the nodes also has significant impact on the MANET routing protocols. In order to achieve improved efficiency for these networks, we propose the Motion Vector Routing (MoVeR) protocol. MoVeR is a position based routing protocol for MANET communications that uses the motion information of mobile nodes to determine how to route the packets. MoVeR predicts the future positions of mobile nodes, based on motion vectors containing current and previous position, and velocity information. The protocol is designed for applications in which we expect that nodes will have access to a position service. We also assume the availability of a location service by which the sender can obtain an initial estimate of the location of the destination. Nodes using the MoVeR protocol distribute the routing information to neighbors in one-hop transmission range. Given the position information, MoVeR can potentially employ one of several forwarding strategies. The implementation used for this research employs a greedy algorithm forwarding the packet to the neighbor such that the neighbor is closer to the destination in the near future. Since the forwarding strategy could be subject to local minima problems, the algorithm also includes a recovery mode which is activated when this problem has occurred. In the recovery mode, the protocol traverses the planarized graph to the destination. MoVeR is a localized routing protocol and therefore exhibits reduced control overhead compared to protocols which maintain a global topology. The mobility prediction capability of MoVeR improves routing performance in several types of sophisticated mobility scenarios. We describe the MoVeR protocol algorithm, implementation, and simulation results show that MoVeR gives improved performance compared to Greedy Perimeter Stateless Routing and Dynamic Source Routing.