The Research Of Topology Management On FCCN-based MANET

In Mobile Ad hoc Network (MANET) all nodes are equal, without central control node. They not only play the role of common mobile terminators, but also have the ability of packet forwarding. Therefore, the route between two arbitrary nodes in MANET is multi-hop. Compared to other virtual topology structures applicable to MANET, Fully Connected Cubic Network (FCCN) has outstanding characteristics of expansibility, short delay, simple routing algorithm and balanced load.The basic composition of FCCN is a hypercube of 8 nodes. Since each node of FCCN has a constant node degree, the newly-entered node will be located in higher layer automatically and make no effect to the former structure. The load borne by every node of the same layer is balanced, for example the 8 Unconnected Gate Nodes (UGN) link two layers jointly and averagely. Once FCCN is built up, there is no need of a central control node to maintain the topology structure. The routing algorithm of FCCN is simple and has an excellent performance since only based on the source node (Source) and the destination node (Destination) could the route be determined. Therefore, a shorter delay is achieved when data transmitted between two arbitrary nodes of FCCN.In this master thesis a distributed algorithm of setting up, maintaining and rebuilding FCCN in MANET is presented. As the basic composition of FCCN, the hypercube of 8 nodes is a construction element of building FCCN. According to the tree structure, the hypercube is formed hierarchically. To make the process of building hierarchical FCCN topology converge fast, some types of specific nodes are abstracted to optimize the cubes' expanding order. The virtual topology is forward through the route determined by the special nodes until the expanding process gets back to the cube launching the process. The inherent constraint relations between nodes of the topology structure are also dealt with in the process to make every node enter the existing structure smoothly.The building algorithm is accomplished in the simulator OPNET according to its modeling mode. The correctness of the algorithm is validated. The algorithms of maintaining and rebuilding FCCN are also simulated. The statistic analysis to the building algorithm's converging time andoverhead shows that the algorithm meets the basic design requirement.