The Design And Implementation Of The PPP Conformance Testing System Based On TTCN-3

The widely spread of information and communication services have accelerated the research and development of the protocol, A protocol is a collection of a set of rules and formats, which can make communication between entities with each other. However, Protocols are mostly in the form of text described by natural language, the structure of this kind of description has defects, for example, it is not complete, not standard, which may produce misunderstanding. So the different understanding in the protocol contents, will make different equipment manufacturers. Therefore, considering interoperability between each vendor, testing must be conducted to ensure the equipments meet the protocol specifications.Protocol implementation is a process of development based on the protocol standard to realize interoperability. However, in the process of implementation, different manufacturers may have different understanding of protocol specification, which lead to use of different option parameters, making interoperability between devices impossible. Protocol conformance test can solve this problem, the purpose of conformance testing is to check all the implemented protocols whether conform to the rules or not. TTCN-3 is a language, which specially designed for testing, the application of TTCN-3 is very flexible and powerful. In addition, By defining a message format, sending and receiving message to interact with equipment, in this way,TTCN-3 complete the protocol conformance testing.Based on the project requirements in H3 C, after learning related conformance test knowledge and RFC specification of the PPP protocol, we finished the PPP conformance test system based on TTCN-3, used communication equipment produced by H3 C, built environment, verified the PPP consistency. In this paper, the main research contents and works are as follows:First of all, we studied the principle of conformance testing, took PPP as the research object, after thoroughly analyzing PPP specification RFC1661 and project requirements, writed the PPP test cases; Then we learned TTCN-3 language syntax structure, according to the protocol test methods and TTCN-3 workflow, especially, implemented the conformance system with TTCN-3 language. In addition, we mastered H3 C switches and routers, and built a complex network, also put it in use.We studied the PPP module, and mastered its background, message interaction, structure, and so on. We also developed the PPP conformance scheme, and conformance script.Second, we used H3 C communication equipment to verify the PPP protocol. At the same time, we recorded the process carefully, examined the device under test, checked the packet senting situation and the test points that had problems, found the problems and solved them in time. After the execution, we carefully checked the log, submitted and reviewed the report.Third, Verified the MSR50-60 serials router’s PPP protocol conformance.