The Improvement Of Direct Test Controller And Test Experiment In Multi-Point Testing

Testing of subnetworks and relay devices (routers or switches), especially for performance testing and evaluation, demands simultaneous observation and test at multi-points (multi-ports for a single relay device, or multiple observation points in a subnetwork) with the same or different test data (concurrency); and demonds coordination. Consequently, neither the "Transverse test method" (TTM) nor the "Loop-back Test Method, LTM) defined in ISO 9646 can satisfy the requirements of multi-point testing. For this reason, Sichuan Network Communication Technology Key Laboratory (SC-Netcom Lab) has introduced a generic test method called CMC-TTM (Coordinated Multi-Point Concurrent -Transverse Test Method) and been developing a Distributed Coordinated Multi-point Concurrent Test System (DCMC-TS) based on this method. This is the general background of the research work presented in this MSc dissertation.The DCMC-TS is a two-level test system consisting of a CMC-TM (Coordinated Multi-point Concurrent - Test Manager) at the top and multiple DTCs (Direct Test Controllers) at the bottom. CMC-TM and DTCs are interconnected via a local network or subnetwork under test. Functions of existing DTC must be extended to enable a DTC acting as an independent tester (for one or two-port testing for a single relay device) or a direct test controller for multi-point testing. This is exactly the main research topic involved in this dissertation.A single DTC involves, at most, two test & observation points and coordination between them can easily be defined with the TTCN-3(Testing and Test Control Notation Version 3). However, coordination for multi-point testing needs serious consideration. A widely used approach is to expand TTCN-3 so as to enable description of synchronization position and manner in a test case for DTC. Unlike the common approach, the athor solves this problem by modification of the TTCN-3 compiler. The merits of this approach include: 1) a test case defined in standard TTCN-3 can be applied to both two- point testing and multi-point testing; 2) synchronization position and manner can easily be inserted automatically during parameterization of a test case. Another issue dealt in this dissertation is how to generate test traffic to meet test requiremts. The work releted to these two issues represents the main contributions of this dissertation.Development work presented in the thesis includes:Functional extention and modification to existing TTCN-3/C Compiler in order to adapt to multi-point testingImplementation of Multi-Point Testing - Coordination Management Protocol in DTC to enable coordination between DTCs & CMC-TMModification to DTC user-interace module to make it feasible for real testingAs a result of Integration of DTC components, an experimental DTC supporting multi-point testing is fledged. Joint test experiments with Coordinated Multi-point Concurrent - Test Manager (CMC-TM) have shown that the modified DTC is compliant to its design goal. The author belives that with futher test experiments and optimization to DTC, a prototype of Distributed Coordinated Multi-point Concurrent - Test System (DCMC-TS) can be developed.