Research On Routing Technology For Heterogeneous Wireless Mesh Networks

With the development of wireless communication technology and Internet of Things technology,wireless mesh networks are gradually showing a trend of heterogeneity.Compared with homogeneous wireless mesh networks,heterogeneous wireless mesh networks integrate various networks with different network architectures,transmission rates,transmission distances and spectrum resources into a whole,which can effectively improve network coverage and quality of service(QoS),so it has attracted the attention of academia and industry in recent years.Due to the heterogeneous characteristics of architecture and links,heterogeneous wireless mesh networks are more suitable for solving the QoS requirements of various types of services.Although there are many mature routing technologies in homogeneous wireless mesh networks,these routing technologies do not consider the heterogeneity of network architecture and links in the route discovery process.Therefore,this thesis has carried out the following research on the routing technology under the heterogeneous wireless mesh network:Aiming at the problem of broadcast storm caused by simultaneous broadcasting of multiple interfaces during the process of heterogeneous wireless mesh network routing discovery and the heterogeneity of the network,this thesis implements a bandwidth guaranteed routing protocol named BRPS(Bandwidth guaranteed Routing Protocol based on Selective broadcast mechanism)based on selective broadcast mechanism.Considering the heterogeneity of network architecture,spectrum resources,bandwidth and transmission distance,First,BRPS proposes the measurement mechanism of interface forwarding capability,link remaining bandwidth,path remaining bandwidth.Besides,in the process of route discovery,a selective broadcast strategy is proposed based on the measurement of interface forwarding capability.Finally,the optimal path selection algorithm is proposed with the maximum remaining path bandwidth as the optimization objective and the cost and delay as constraints.Through NS3 simulation and comparison with existing technologies,with the increase of packet transmission rate,the throughput of BRPS can be increased by about 30%;with the increase of the number of data streams,BRPS has advantages in end-to-end average delay and throughput.Aiming at the diversified characteristics of various terminal service requirements in heterogeneous wireless mesh networks,this paper implements a QoS guaranteed routing protocol named QRPDSR(QoS guaranteed Routing Protocol with Diverse Service Requirements)for diversified service requirements.In QRPDSR,on the basis of considering the heterogeneity of the network architecture,the end-to-end delay,delay jitter and node cache occupancy rate of the path are evaluated in detail.Accounting that the different levels of node cache occupancy,link delay or link delay jitter have different effects on the entire path,the fuzzy logic algorithm is introduced in the evaluation process.The core idea of the algorithm is to divide the node cache occupancy,link delay and link delay jitter into fuzzy sets according to the levels,and divide each set into different weights.On the basis of determining the membership function of each set,the membership values of the measures are weighted to get a new measure.On the basis of the above metrics,by adding the QoS field in the routing request packet,the optimal path between the source and destination nodes can be found according to the service requirements.Through NS3 simulation and comparison with existing technologies,it can be found that QRPDSR has certain advantages in throughput and end-to-end delay performance for services with low delay jitter requirements;for services with low throughput requirements,QRPDSR has certain improvement in delay and delay jitter performance.Finally,the thesis summarizes the full text and puts forward a prospect for the next research work.