Hyper-mutation Based Genetic Algorithms for Dynamic Multicast Routing Problem in Mobile Ad Hoc Networks

In this paper, the problem of dynamic multicast routing in mobile ad hoc networks is investigated. Lots of interesting works have been done on multicast routing since it is proved to be a NP-hard problem. However, most of them consider the static network scenarios only and the multicast tree cannot adapt to the topological changes. In a mobile ad hoc network (MANET), the network topology keeps changing due to its inherent characteristics such as node mobility and energy conservation. Therefore, an effective multicast algorithm should adapt the best multicast tree to the changes accordingly. In this paper, we propose to use two types of hyper-mutation genetic algorithms (GAs) to solve the dynamic multicast routing problem in MANETs. The two GAs are named as high low hyper-mutation GA (hlHMGA) and gradual hyper-mutation GA (grHMGA), respectively. The experimental results show that the first type of hyper-mutation GA (i.e., hlHMGA) can quickly adapt to the environmental changes (i.e., the network topology changes) and produce high quality solutions following each change.