Research On Ad Hoc QoS Routing

Mobile Ad Hoc Network(MANET)is a complex,temporary,distributed multi-hop autonomous network system,without using any fixed base station deployment.Due to characteristics of MANET such as lack of central coordination,mobility of hosts,self-organizing,rapid deployment,MANET network can be widely used in many aspects of social life,including military,natural disaster emergency response,scientific investigation,interactive lectures,emergency communications and other fields.In the existing research work,MANET network has proposed many kinds of routing protocols including FSR,OLSR,DSR,AODV and etc.However,under the influence of bandwidth limitation,link time-varying and dynamically varying network topology,it is still the main research hotspot to satisfy the QoS of the upper layer service.The content of this thesis is to analyze the standard OLSR protocol,and put forward a new multi-relay MPR selection algorithm to improve the stability,robustness and routing efficiency of the original OLSR routing protocol.In order to achieve the QoS guarantee in the routing protocol,this thesis implements the shortest path routing protocol with QoS guarantee by using the metrics of node link bandwidth measurement and delay measurement in the OLSR protocol.In addition,Multi-relay MPR is the key factor of OLSR protocol to reduce message flooding in node network.By optimizing the selection of multi-relay MPR set and controlling the size of the set,the message transmission overhead of network nodes can be reduced and the complexity of node routing can be reduced.However,the MPRs derived from the MPR set selection algorithm in the standard OLSR protocol do not consider the stability of the nodes.Therefore,this thesis proposes a new multi-relay node selection algorithm called QMPR selection algorithm.Based on the stability of the node,the multi-path routing algorithm was added into the original protocol,so as to implement the QoS-based multi-path routing protocol called MQ-OLSR.Finally,our simulation results show that the improved OLSR protocol MQ-OLSR is superior to the standard OLSR routing protocol in respect of delay,bandwidth and packet loss rate.