The Research & Realization Of VOD Simulation Server Based On IP Network In The Test Of Triple Play Operation

Along with the incessant progress of the communication technologies and the durative expansion, the development of the telecom services is tending to diversification and individuation. In the communication industry which is more competitive, each telecom operator is trying to combine multiple operations to supply various intergrated information services to users. At present, the Triple Play service based on IP network, which combines the voice, video and data services together, has been got much attention. It can provide kinds of services including telephone conference, VoIP, IPTV and VOD to users. Delivering these complex services over current converged network presents a number of technical challenges to the deploying process by operators, however. The operation of the Triple Play service is faced with a lot of difficulties. So it's much important to reliably test the Triple Play service.The Triple Play service test mainly includes testing the network traffic, network devices and operation scenarios. Spirent TestCenter^TM (a product of Spirent Communications, Inc) can be used to simulate a range of real servers such as Web servers, FTP servers, Telnet servers and streaming servers, aiming at the test requirement mentioned above to fully test the Triple Play simulation scenarios. And in the whole Triple Play test system, the VOD (Video on Demand) service test and its simulation server are the important portions and components.So realizeing the application-level VOD video simulation server can not only meet the requirement of the video service test in the Triple Play test system, but also has the advantage of fast deploying test devices. The VOD simulation server can generate and handle thousands of concurrent streaming requests, enabling you to assess the perforamance and capacity of large streaming media farms and streamingaware devices using QuickTime, Real Networks, and Windows Media streaming media players.This paper consults the structure of the VOD system, adopts corresponding video transmission protocols and coding standards, utilizes the technologies such as the format conversion, data encapsulation, session control and so on, designs the voice/video coding and test modules in the VOD system, and integrated these modules to develop an IP-based VOD video simulation server. The project can code demanded video files by H.261/H.263/MPEG-4 (etc.) for the video part and G.711/G.723/G.729 (etc.) for the voice part, to resolve the problem that the decode capability is different between the clients. And it can support more coding formats, simplify the network hardware devices and system structure, decrease the test cost compared with existing streaming media servers. So it effectively simulates a real VOD server to enhance the reliability of Triple Play system test, and has significant application foreground.