The Research On Routing Algorithm Optimizing Of AODV Based On AD HOC Network

Ad Hoc Network was firstly exploited for military use and, after 40 years' development, further applied in civil fields, such as local area network, personal wireless mobile communication, etc. It is predicted that it will be a core component of future mobile communication technology. The flexible movement of nodes in Ad Hoc Network leads to the instability of Topology, which means that the traditional routing protocol of the Internet is not applicable to Ad Hoc Network. Therefore, a suitable routing algorithm should be adopted to solve the routing problem in Ad Hoc Network. In this sense, optimization of routing protocol algorithm becomes the focus in Ad Hoc Network.This thesis firstly introduces the status quo and offers some prospects of Ad Hoc Network, and then briefly illustrates routing protocol in current networks, particularly the AODV routing protocol. Next it makes a brief introduction to improved AODV routing algorithm. ADOV (Ad Hoc On Demand Distance Vector) is a routing protocol on the basis of distance-vector, including routing discovery and maintenance. But it fails to take into consideration the stability of links and the state of mobile nodes. So any disconnection needs a new routine to be found, which leads to delay and higher expenses of the network.Aiming at these problems, this thesis puts forward FRR-AODV (Fast Response Reroute—AODV), which owns three advantages:To begin with, it proposes a link-state forecasting method, which effectively prevents links from disconnecting. Next, a spare routing algorithm is put forward. With it, the expenses on rerouting could be reduced once the routing disconnects. Lastly, a mechanism to recover the routing is presented. When the routing breaks while the spare routing unusable, routing link will reconnect from the previous hop, instead of the source node.In the end, by using NS2 network simulator, a comparative analysis is held between FRR-ADOV routing algorithm and AODV protocol on their properties. The result shows that FRR-ADOV routing algorithm reduces routing breaks, packet delivery fraction and the average end-to-end delay, and comes to the conclusion that FRR-ADOV is superior to AODV protocol.