Investigation On TORA Routing Protocol In Ad Hoc Networks And Its Improvement

Internet of things、Wireless Sensor Networks and Wireless Body Area Network are hot topics in communication field nowadays. One common characteristic of them is that they are all self-organized, which means they can be considered as the Ad Hoc networks.Routing mechanism is one of the main research directions. Ad Hoc network is mainly used in wireless mobile communication. Energy consumption is an important factor that restricts the performance of wireless network. Therefore, routing algorithm of energy-efficiency is required.Much energy-efficiency method is introduced to Ad Hoc network routing protocols. Among these protocols, there is a Temporally Ordered Routing Algorithm(TORA) which has better robustness and higher efficiency than many others, and it is widely applied to Ad Hoc network.When the topology of wireless network seldom changes, its routing mechanism will only transfer messages on a single path, which means energy of some intermediate nodes will run out quickly, which reduces the reliability of network and shortens the life time of network. In addition, TORA is usually used in the environment of large-scale Ad Hoc network for its better robustness, while it needs to establish routing path by periodic broadcasting to the entire network, which introduce great overhead, All in all, it is not a good way to extend the life time of network and reduce the energy consumption of the network.For the deficiencies of the TORA protocol mentioned above, we propose Multipoint Relay(MPR) to improve the TORA protocol in this paper.Comparing two TORA protocols in respect of network average delay and the ratio of packet delivery, we find that the improved TORA protocol(TORA-MPR) performs better than the original TORA protocol; In consideration of the fact that TORA protocol needs great network overhead to establish routing path in large-scale Ad Hoc networks, we use a cluster based algorithm to improve the TORA protocol, the simulation results prove that the improved Cluster-Based TORA protocol has a high network reliability and reduces the network overhead.