Research On TTCN-3 Compiling Techniques And Implementation

The background of the research work presented in this dissertation include: A) Testing of IPv6 protocol stack, especially IPv6 routers, has become one of the key technologies to migrate from the existing Internet to the emerging Next Generation Internet, and B) Existing techniques in conformance and performance testing for modem high-speed routers with multiple ports are inadequate. In order to test a router thoroughly, it is prerequisite to emulate its external real working conditions. However, existing testing techniques are not fledged for this purpose. SichuanNetwork Communication Key Laboratory (SC-NETCOM LAB) has been researching on the techniques for multi-port concurrent test and developing the Concurrent Multi-Port Test System (CMPTS), of which the Two Port Tester (TPT) forms an important part. The work presented in this dissertation is dedicated to TTCN-3 translation techniques for TPT, which translates the test control data in TTCN-3 to executable codes.There are two typical approaches in translating specifications in programming languages: interpreting or compiling, of which interpreting approach is most widely used in handling TTCN-3 specifications. In view that modern routers are high-speed devices with multi-ports, therefore short on-line processing time should have higher priority in system design compared with other features such as storage requirements and flexibility in modification of executable codes, and consequently the compiling approach is adopted.Compiling of test specifications in TTCN-3 is similar to other compiling processes, which involve lexical analysis, syntax analysis, semantic analysis, and code generation. In order to incorporate the compiled codes with other parts in TPT, a two-stage compiling approach is designed: first the specifications in TTCN-3 is compiled into "C" and then to compile into machine executable codes. No code-optimization has been considered in TTCN-3/C compiling and left it for the "C" compiler. The TTCN-3/C compiler first scans the source code in TTCN-3, performs syntax analysis and semantic analysis, and finally generates the C code viascanning through the syntax tree in conjunction with symbol tables.The author's work involves lexical analysis, syntax analysis, and semantic analysis, and an emphasis has been given to techniques of code generation. As the TTCN-3/C compiler is the support tool for TPT, to some extent it is tester-dependent. Therefore, the resultant "C" code for test control data has to be jointly compiled into machine code with "C" code for the traverser (which traverses through a single test case) and with the E/D (Encoder/Decoder) of PDU (Protocol Data Units) of the protocol under test. The significance of work presented in the dissertation not only provides an important tool for TPT but also provides a basis for CMPTS under development, which leaves the burden of control of a pair of ports to TPT.