Using Fuzzy Logic in Hybrid Multihop Wireless Networks

In order to extend the use of Mobile ad hoc networks (MANET) to commercial applications, it is necessary to provide a mechanism to integrate this kind of networks into the Internet. In this way, MANETs could be utilized in visiting theme parks, commercial centers and military scenarios. The interconnection of MANETs and the Internet is supported by a Gateway. The gateway is responsible for informing about some configuration parameters as well as for enabling the creation of the routes to the Internet in the MANET nodes. For these tasks, several control messages are generated. The method in which these messages are originated defines the existing Integration Supports for MANETs. In particular, under the hybrid Global Connectivity support, the Gateway generates periodic Modified Router Advertisements (MRA) which are broadcast in an area close to the Gateway. The optimum values to define the periodicity of these messages and the diameter (number of hops) of the area in which they are propagated depend on the network conditions. Therefore, an automatic and dynamic algorithm is recommended to be implemented in the Gateway to adjust these two parameters. In this sense, this paper presents a technique by which the interval of emission of the MRA messages is controlled by a fuzzy system. The fuzzy system captures several network conditions such as the link stability or the number of sources. The simulation results show that the proposed scheme outperforms other adaptive approaches for the gateway discovery in MANETs.