Providing datagram multicasting service to mobile ad-hoc network systems.

摘要

Current wireless internetworking systems are capable of providing uninterrupted data communication services to mobile users. Mobile Ad-hoc Network (MANET) is a special type of wireless network. In MANET mobile nodes are equipped with wireless communication interfaces and capable of moving at will. Subject to communication parameters, network links are established as nodes move close to each other and broken when nodes move far apart. In MANET there is no need for any fixed communication infrastructure such as towers and cables.; The dynamic nature of MANET topologies, paired with all special characteristics of wireless communication, poses MANET routing as a special challenge for the research community. The goal of this dissertation research is to address the problem of providing datagram multicasting service in middle to large size MANETs. Our research focus is to develop a rather general multicasting solution for conventional IP-based mobile computing devices such as laptops and Personal Digital Assistants (PDAs). The solution needs to be scalable, adaptive, and bandwidth efficient. At the same time, the solution can be easily deployed and integrated into the existing Internet.; Two approaches are proposed from the research. The first approach views MANETs as isolated and self-sufficient network entities, and attempts to solve the multicasting problem within the boundaries of the MANETs. A vertically coupled protocol stack structure for MANET multicast routing protocol implementation is also proposed. The second approach adopts a hierarchical structure. It assumes the existence of a separate backbone network as well as a small number of access points attached to this backbone, in addition to a large number of MANET nodes, and thus organizes the whole network as a Wireless Extension Network (WEN) of the backbone network. WEN may contain large mobile node population while the diameter (or depth) of any MANET cloud is kept limited. The WEN approach is able to provide scalable and efficient multicasting service to middle to large MANET systems.