Research And Deployment On Quality Of Service In Packet Transport Network

Packet Transport Network(PTN) has been widely used to carry access traffic of 2G/3G/4G mobile cell networks and full-service traffic. PTN has high reliability and powerful control and management capabilities. Furthermore, based on the packet switching technique, PTN aso has high transmission efficiency. With the large-scale deployment of 4G mobile cell networks, traffic volume will increase explosively, and it is challenging to carry 4G access traffic on PTN. In oder to guarantee the Qo S ruequirments of different traffic, it is very important to deploy Qo S schemes in PTNs. To this end, we have to first study the key technologes and the Qo S gurantee mechanisms of PTN, and then based on the practical situation of network provider’s PTN and traffic requirements, we customize the Qo S gurantee schemes for the network provider.Firstly, we briefly introduce the key technologies uesed in PTN, including modularized system architecture, physical and logical layer model,packet forwarding mechanisms, OAM fuction, and protection mechanisms. We study the Diff Serv model and the process of Qo S schemes, and analyse the traffic classification schemes, traffic policing schemes, congestion control and management schemes, and traffic shaping schemes. Moreover, we analyse the process of Qo S gurantee schemes for ethernet traffic and CES traffic.Secondly, we make a detailed analysis for a network provider’s PTN, including traffic model,protection mechanisms,bandwidth requirments, forwarding priorities and queue scheduling strategies. Based on the analysis, we designed Qo S gurantee schemes, including traffic classification schemes, traffic policing schemes, priority mapping schemes, queue scheduling schemes and congestion control schemes, for the PTN.At last, extensive tests are conducted to verify the efficitiveness of deployed Qo S schemes on a commercial PTN. We test the forwarding performance of traffic demands with different priorities, verify the effect of traffic policing in different action point, and compare the quality of all services of the PTN under the deployed Qo S schemes. The results demonstrate that the deployed Qo S schemes fulfill the requirments of the current network and realize the differentiated service.