Improvement And Implementation Of Olsr Routing Protocol In Ad-hoc Networks

Ad-hoc network is a new and developing network technology in current wireless communication domain. Its outstanding characteristic is that it can provide flexible and convenient communication without the presence or use of a fixed infrastructure. Therefore, ad hoc network extends the application region of mobile communication and it is just rapidly penetrating from military communication to relevant common communications.Ad-hoc network, also called multi-hop network, operates in distributed mode. Each node, which is not only a host, but also a router, can enter into or leave from the network freely. At present routing protocol is one of the main problems about Ad-hoc network.stand or fall of routing protocol will affect the quality of communication service directly as well as the efficiency of system resource utilization. So routing protocol is the majority of building Ad hoc network and also the primary hotpot and difficulty.After a survey of the classic ad hoc routing protocols and the characteristics of ad hoc networks, an OLSR-based routing protocol, AH-OLSR, which is self-adaptive and hazy-sighted, is presented. The protocol is self-adaptive in the sense that it adaptively adjusts TC message dissemination according to different node speed. The protocol is hazy-sighted in the sense that it employs different frequencies of TC message dissemination for nodes with different distance from the computing node. In addition, the number of hazy levels is automatically set. This hazy-sighted algorithm effectively reduces the control overhead, and when accompanied with the self-adaptive module, makes the protocol focus on fast-moving nodes as well as nearby nodes, meanwhile improves network scalability and survivability, reduces convergence time, and consequently enhances network performance.An AH-OLSR routing protocol development platform is then constructed based on Vxworks and the TCP/IP protocol suite, using PowerPC processor MPC8260. Eventually some simple routing functions are realized based on this platform.In the end, a further research perspective is put forward based on the work of this dissertation.