Research On POTN Application In Railway Carrying Network

As the foundation of the ground network, large amounts of service needs to be transmitted by Railway Communication Carrying Network. With the development of railway communication network, the carrying network is required to provide higher traffic and more complicated transmission network structure. According to the High-speed Train Future Service Requirements Analysis Report investigated by International Union of Railways (UIC) information, there will be more than 200 kinds of information service to be transmitted through the optical transport network to meet the demand of the high security of the train operation. So a network should be built which has high stability, easy maintenance and management to bear the burden of railway communication.At present, Optical Transport Network (OTN) and Packet Transport Network (PTN) have been used in railway communication. But there are some problems and deficiency in their application, such as OTN has large capacity, but it can’t transfer small particles service directly, also consumes a lot of power and occupies room; PTN can meet the demand of IP, improve the utilization rate of bandwidth, enhance the OAM, and provide QoS and protection for service, but its system capacity is limited. In order to solve these problems it is urgent to combine OTN and PTN.There are several advantages of Packet Optical Transport Network (POTN) as follows:POTN has larger exchange capacity, it can provide a better transmission platform for large capacity service; POTN can provide uniform carrying platform for different types of service, such as SDH, IP, OTN, FC, ATM, etc., it realizes that almost all service shares a net, which greatly saves resources and reduces the space; Moreover, it has the packet switching function of PTN, thus it realizes the load and scheduling of the service. Therefore POTN is raised to apply in railway in this thesis.The main works in this thesis are as follows:(1) The technology of OTN and PTN, analyzes the basic principle, structure, protection technology of them and the joint network model of OTN technology and PTN technology, analyzes the advantages and disadvantages of the various model.(2) The technology of POTN, analyze the basic principle, protection technology, network survivability of POTN technology and POTN application scenarios in operator network.(3) Analyze the development situation of Railway Carrying Network, and analyzes situation of the OTN and PTN technology application in railway communication network, summary the problems and deficiencies in Railway Carrying Network, then point out the technology needs and service requirements of POTN technology applying in Railway Carrying Network, and finally establish the networking models of POTN in Railway Carrying Network, research on the most suitable model in Railway Carrying Network deeply and analyze the traffic flow, bandwidth, which is the main focus of the thesis.