Research And Development Of The Executable Test Case Generation System In TPT

Future routers/switches will be characterized as multi-port devices with high-speed switching capability and should be able to satisfy different Qualities of Service required by multimedia network applications. Such requirements, in turn, demand test systems for routers and switches being able to simulate real operation environment for routers and switches and to give comprehensive evaluation tests. This requirement has spurred the activities of research on multi-port concurrent test method and development of relevant test systems at Sichuan Network Communication Technology Laboratory (SC-Netcom Lab). The test system under development at SC-Netcom Lab is called Distributed Multi-port Concurrent Test System (DMC-TS), which consists of two interconnected functional parts: the upper part - Multi-Port Concurrent Tester (MPCT) and the lower part - multiple "Two-Port Tester (TPT)". The work presented in this dissertation is directly involved with TPT.A TPT is composed of a test execution part (also being referred to as front-system for it directly interacts with operator) and support tools. The author has been devoted himself to development of the Single Test Case Executor (STCE), a part conceptually belonging to execution part in TPT. Nevertheless, since we adopted compiling approach in handling test control data, the STCE is merged into executable test cases and automatically generated by the test case compiler. Consequently, the author's work is turned into investigating how to automatically generate STCE in the SC-Netcom compiler for TTCN-3 (Testing and Test Control Notation), a standard test description language.Single-pass and multi-pass scanning has been widely used in TTCN compilers, but a two-pass scanning approach is adopted to make a trade-off between existing approaches. Through morphology, grammar, and semantics analysis, grammar trees and symbol tables are formed and intermediate code in C language are finally produced after code optimization. The final executable test control data (ETCD) can be obtained via C compiler. The function of STCE is to send out test data, receive and logging responses from the Router Under Test (RUT), and to make testconclusion according to test case description. Therefore, STCE is an important part of the SC-Netcom TTCN-3 compiler.The novelty of STCE produced by the author's STCE-generator lies in a TSTT-driven (Test State Transition Table driven) control mechanism. A test state corresponds to a test node in a test tree specified in test cases but there is no one-to-one mapping relationship between a "test state transition table" and the "state transition table" defined in protocol specifications. In a sense, a test state set can be viewed as an expanded protocol state set of a protocol with more details and ramifications in order to fulfill test purposes. With the TSTT-driven approach, all possible state transitions can be traversed as long as they are defined in test specification. Apart from the work relevant to STCE-generation, the author has also completed the Encoder/Decoder for IP and adaptation module between IP and MAC to enable an IP layer testing and the code optimization and generation.The main contribution of this dissertation can be summarized as: A. having completed an STCE-based TTCN-3 compiler based on previous works in compiler development and provided a sound basis for future development of TPT as well as DMC-TS;B. having carried out preliminary tests on an IP implementation in a level-3 switch with author designed test cases, Encoder/Decoder, and IP-MAC adaptation module and shown that the design goal for TTCN-3 compiler is reached.