Research On The QoS Routing Algorithm In MANET Based On Ant Algorithm

Mobile Ad hoc network(MANET) is a kind of mobile multi-hop and self-organized wireless network, it is getting more and more attractive and can be used in military fields, emergency rescue, disaster recovery, sensor network,scientific exploration and video conference.the growing demand of the real-time multimedia applications requirements the MANET network providing quality of service (QoS) .Different with the traditional fixed network and mobile communication network, besides satisfying the requirement of the QoS ,many characters of MANET should be considered, such as limited bandwidth, dynamic topology, the inaccurate link state information, non-centralized control and limited resources, These features make how to provide QoS guarantee in the MANET become research focus, as well as a difficult issues.In this article, some typical routing protocols in MANET and QoS model were analyzed completely, in succession characteristic ant algorithm was studied, and recent researches about ant algorithm were discussed. In order to improve the slow constringency and preference to stagnancy of ant algorithm, an original routing algorithm-- Ant-based Mulit-constrained QoS Routing Algorithm, AMQRA in brief was developed. In this algorithm the founded path marked by path grade which, along with the load of nodes, was used to update the pheromone. In reverse the pheromone directs the algorithm to converge to the path which has the best QoS. On the other hand the AMQRA also achieves load-balancing. Therefore this algorithm has the properties of high packet delivery ratio ,adaptive, scalable.The simulation results show that the AMQRA has higher packet delivery ratio and less average end-to-end delay in sacrifice of the routing overhead. Moreover the routing overhead of AMQRA is a little more than ARA. Compare with QAODV and ARA, the AMQRA improved by 9%-22% on the packet delivery ratio, and it reduced by 14%-16.7% on average end-to-end delay. Especially in the case of the rapidly changing network topology, AMQRA has shown good performance.