| Next Generation Network (NGN) is a service-focused, integrated and opening network architecture which can provide various services including voice, data and multimedia. Softswitch is the core technology of NGN that provides Real-time Services'call and connection control. SIP and H.248 are the most important signaling protocols of Softswitch signaling protocol system. Calling Generator software (Call-tester) based on H.248 and SIP signaling protocols is designed in the subject.At first, the background, current application and developing trend in the future of Next Generation Network (NGN) is introduced in the paper. Then, Softswitch technology is discussed in detail, including its background, function definition, characteristics, function model, networks architecture and application models. We also give a particular description of the application models of SIP and H.248 protocol in Softswitch architecture. At the same time, the correlative protocol stacks involved in the subject is discussed amply, such as SIP and H.248 protocol stacks. On this basis we construct a platform of software system architecture model of the Call-tester and describe detailedly the function of each module, the principle of the realization, algorithms, data structures, function interface and flow charts. We also realize the Call-tester system by Software programming.At last, we test the performance and detection efficiency of the Call-tester software system by an example. And then, we analyze the existing problems in the software system and their solutions. At present, the switching equipments of NGN tested by the Call-tester software system are successfully used in some telegraphic departments in Guangdong and other places. The calling unit stands the test of explosive growth of call quantity and been well received by users. |
PDF Full Text Request