| With the development of science and technology, people are more readily to communicate in a wireless way instead of a traditional wired one. In the next generation wireless communication system, it is a base requirement that mobile equipments can be organized by themselves into connected networks. Without any aid of infrastructure, an efficient and dynamical communication system can provide convenient communication services freely. In past several years, researchers around the world keep on developing a new networks infrastructure, named MANET (Mobile Ad hoc Network). Because of its incomparable merits in construction and economy, a MANET works force was set up by IETF for evaluation and standardization of key technologies in Mobile Ad hoc networks.It is different from single hop wireless network, Mobile Ad hoc network nodes intercommunicate according to multi-hops data store-forward, which need the support of routing protocols. The regular change of bandwidth and node motivation, pass in and out will result in change topology. The routing protocols will monitor the changing topology, exchange routing information, locate the nodes' position, select and maintain routing. Then they store-forward data for network nodes according to routing. Routing protocol is the hot problem because of it is the base in self-organized network.Nowadays the development of network makes people wish to enjoy the multimedia services in all kinds of networks. It can't be avoid such demand in the practical process of MANET. So QoS routing in MANET is more important than in present IP networks. In this paper, works on multi-path routing load balance, multi-media multi-path routing algorithm, multi-path flow distribution algorithm and multi-media packet scheduler algorithm are represented. The paper is organized as follow:1) In Chapter I we discussed the development of mobile Ad hoc network technologies, analyzed the characteristic of Mobile Ad hoc network, its prospect in the future and research hotspot of Mobile Ad hoc network. Chapter II represent the concept of multi-path routing in Mobile Ad hoc network, as well as it's characteristic and problems it has. After that is a summary of research works represented in this paper.2) Based on the theory that in wired network proper multi-path routing can significantly increase the throughput of network and balance the network load, Chapter III bring forward a new analysis model which can evaluate the performance of multi-path algorithms in Mobile Ad hoc network. By using this model, results shows that regular multi-path routing algorithms can not balance the network load well.3) Concerning the special QoS requirement of video stream, Chapter IV represents a novel multi-path routing protocol and its flow distribution algorithm MRRAA which is developed for multi-media flows in Mobile Ad hoc network. In MRRAA transmitting delay of a route is considered as the most important part in route selecting, and the band-width requirement of the source is considered as well. Since video streams require small delay and the BER of wireless link is relatively high, MRRAA use FEC for error finding and get the best coding speed, so it can make best use of the link resource.4) Not like original multi-path transmitting, the multi-path packet schedule algorithm MPPA represented in Chapter V separated the video stream into fragments and delivers them to different routes using the polling algorithm. This algorithm treats packets in the video stream individually, chooses its route separately. As a result MPPA can greatly reduce the occurrence of packet disorder at the receiver end. Also the starting delay and buffer at the receiver can be minimized since there is no need to rearrange the packets.
|
PDF Full Text Request