Research And Implementation Of SDN Control System In WAN

With the rapid development of the Internet,the increasing traffic and the complicated applications has brought great pressures to traditional network facilities.The existing network is facing huge challenge in extensibility and flexibility.SDN provides a new idea for network management and resource scheduling.It separates control plane from data plane,and enhances the control logical and extendibility of network through centralized management and programmable interface.But till now SDN is still a paradigm confined within data center and LAN area.Because of the complexity of the network device and the diversity of the network structure,there are still many restrictions on using SDN in WAN.Based on the research achievements of SDN for WAN system by our project team[29][30],this paper implement and optimize a SDN control system in WAN.The system implements the agent,the controller and protocol as core technology,contains Policy Management Agent(PMA)and Policy Management Server(PMS).The PMA,as an agent,is used to collect infomation from network devices and control them with command.The PMS,as a controller,can manage and control network device through the protocol between PMS and PMA.PMS also provide the query interface of network,infomation or other interface,so we can build application upon the system to control the network programmablly.This paper focuses on its implementation and optimization details.The main work of this paper is as follows:firstly,researches related with SDN were introduced and analyzed;secondly,our project team's PMS-PMA architecture was introduced;thirdly,development and optimization of the PMS-PMA control system in WAN were introduced in detail.With PMA,the complicated network device now can be accessed and controlled through the existing network management methods such as SNMP,CLI and NETCONF.With PMS,which is the core component of the system,the system can control the legacy network flexibly.At the same time,users can develop corresponding applications to optimize or adjust network business through the data interface and the communication mechanism that PMS provided.Finally,this paper summaries the performance and characteristics of the system,and put forward the outlook on the future development.