Research And Implementation Of SIP Conformance Testing Suite Based On Petri Net

With the evolving of computer and communication technology,open protocol standards and the emerging application methods all the time attract communication network architecture to use IP networks to evolve to next-generation communication network.PSTN network will evolve towards NGN network,GSM and 3G network will evolve towards the derection of IMS,and in the more distant future,we can see the seamless integration of the fixed and mobile network based on IP level.In the course of these exciting changes,SIP is one of the most important control protocols,participate in the development of the network deeply.SIP is a signal-controlling protocol based on internet environment,which breaks through the traditional design of level control of H.323 protocol set,has the scalability,flexibility,interoperability,reusability and other fine properties.As the simplicity,easy to expand,more easier to achieve and other advantages getting the industy's favor,it's gradually becoming an important protocol in NGN and 3G multimedia subsystem domain,and the client softwares, intelligent multimedia terminals,server and Softswitch equipment supporting SIP protocol is emerging continuously.Because of the various version of implementation of SIP protocol causes the poor and difficult issues such as conformance and interconnection.The SIP protocol conformance testing is generating for this problem,in according to the description text of the protocol, to test whether they compliance or the consistent level between RFC3261 standard and the realization. SIP protocol testing is one important branch of protocol testing, is the basis of the interoperability testing and performance testing, the generating technique is the most active area in the conformance protocol testing.Currently, some international provider of testing system has developed some testing tools for SIP protocol.Generalling speaking,these types of testing system are very expensive and with limited kind, these feature greatly limit the widespread use of such products.In the context of above research environment,our research group is committed to the research and implementation of SIP conformance testing suite,apply the Petri-net theory to describe the dynamic model,use the reachability tree algorithm to generate the reachability tree,analyze the tree to exact conformance test sequences,and then get SIP conformance testing suite.In relative to ETSI tesing suite,this testing suite increase the specification and testing capabilities of the NUT,the processes and parameters of the testing content,can test the system performance under various conditions,cover the basic and advanced features, will provide greater assurance and testing coverage,is a further advance in the conformance protocol testing suite.