The Mechanism And Application Of Circuit Emulation Service In PSN

For many years, SDH has set the benchmark for reliability and performance. However, with the change in service mix favoring increasingly packet-centric technologies, Packet Switching Network will replace SDH with a converged network for all service in the future. This replacement has to go through a transitional phase because of the large scale of installed legacy TDM equipment and the services rely on TDM equipment. During this transitional phase, there is a need for a technology allowing seamless transmission of TDM services across the packet switch networks.Circuit Emulation Service (CES) can complete this transmission by emulating the TDM circuit across a packet network using virtual IP tunnel or path, enables synchronous service such as T1/E1over asynchronous PBN or MPLS-TP infrastructure. Through choosing a PTN device that provides Circuit Emulation Service, the operators can converge the TDM traffic into the IP networks without compromising with the revenue streams and service performance or compromising existing infrastructure investment.The author provides an introduction and analysis to Circuit Emulation Service (CES) based on the PTN device SPO1400, including the mechanism, architecture, encapsulation, jitter buffer and synchronization of Circuit Emulation Service. And the author will also introduce the implementation of CES based on the TDM over IP prototype system-SPO1400Multiservice Platform in detail,In addition to the introduction of CES mechanism and implementation, this thesis will also introduce the design of extended function of CES--Circuit Emulation Service Card Protection IP (CES-CCP) based on the Ericsson SPO1400platform. CES-CCP combines the switch protection of internet and devices to provide redundancy protection of Circuit Emulation Service. CES-CCP can ensure the traffic lost time is limited in50ms, so that the customer will not notice the malfunction of the internet or device.Moreover, in the Chapter5, the author put forward a CES-CCP test scheme mainly based on the key technique of CES, application scenarios and the mechanism of CES-CCP. The test scheme aims at verify the performance of Circuit Emulation Service Card Protection IP in different internet infrastructure when carrying different forms of TDM signals. The test includes manual test and automatic test. Through implementing the scheme on SPO1400platform and analyzing the results of the test, the author verified the feasibility of the test scheme and the performance of the CES-CCP.