Research Of Signaling Network Based On DIAMETER Protocol

With the rapid development of mobile communication,4G has arrived,core network has developed to the EPC network and IMS network.The traditional AAA protocol for charging is Radius protocol,which is difficult to satisfy the security,reliability and functional requirements etc.of the core network.And it also has been difficult to apply to today’s rapid development of the communication network.Then Diameter protocol which is based on IP protocol is used in the EPC network,IMS network and PCC network as the new AAA protocol.LTE introduces several interfaces of Diameter signaling,such as S6a,Gx,Rx,Cx,Sh,Zh,SLg,SLh and so on,which demands Diameter signaling addressing.If the whole network takes the way of connecting with each other,it will increase the complexity and inefficiency of the comunication network,and it is difficult to manage.Therefore,like the traditional signaling network,Diameter signaling network also has some demands of simplifying the data configuration,converging the signaling links and hiding the network topology.Diameter signaling network uses the way of the relay route,which uses DRA to transfer Diameter signaling and build Diameter signaling network.In this paper,the main contents and innovative points are as follows.(1)Investigating the development of Diameter signaling network,analyzing the interface and architecture of Diameter signaling network systematically,and sumarizing the function of DRA(Diameter Routing Agent)in the Diameter signaling network.(2)Through the research of Diameter signaling network,we know that the routing scheme of the signaling network is the static routing scheme,which can satisfy the routing function of the signaling network.However,when equipment or link failure occurs,the efficiency of network will decrease dramatically,and in some cases will finally come to signaling storm.On the basis of this,I put forward a new routing scheme of the signaling network,dynamic routing scheme,which can significantly reduce the times of congestion control and rerouting(the more times,the more delay and network overhead),effectively improve the processing efficiency of the global network.In the end,I make a detailed comparison between the dynamic routing scheme and the static routing scheme,from the end to end delay and network processing overhead.It is concluded that the dynamic routing scheme can effectively reduce the end-to-end delay and network processing overhead.(3)In order to meet the requirement of the long-term evolution of low signaling transmission delay and the requirement of core network virtualization,Diameter signaling network virtualization is proposed in this paper.Signaling network virtualization includes DRA virtualization and signaling nodes(EPC,IMS,PCC network element)virtualization.This thesis focuses on the DRA virtualization architecture,and compares the DRA.virtualization architecture with the traditional DRA architecture,then analyzes its advantages.Finally,the test of the signaling network virtualization scheme is carried out to verify that the virtual architecture can achieve the basic functions of EPS/IMSI joint attachment and IMS initial registration,which can describe the feasibility of signaling network virtualization architecture.