The Research And Implementation Of Universal Decoder Based On TTCN-3

With the continuous development of next generation network technology, different network communication products are emerging in an endless stream and their relevant communication protocol standards are becoming increasingly abundant. Protocol testing, including Conformance Testing, Interoperability Testing and Performance Test, is the main approach to ensure the accuracy and validity of the implementation of the protocol standards. Nowadays, the new generation protocol and software testing standard, called TTCN-3, which is specified by ETSI (European Telecommunication Standards Institute), has become the mainstream standard of protocol testing with its powerful features and wide application scope.TTCN-3 test system is composed of a number of entities, including TE, TM, CH, CD, TL, SA and PA. In TTCN-3 test system, the important role, called CD (Codec), which is the bridge of data conversion between TTCN-3 test system and the system under test, is the translation functional entity for the TTCN-3 ATS data type instance and network data bitstream. TTCN-3 test system specifies the standard implementation interface of Codec, leaving the implementation of codec to developing engineers of protocol testing tools. So, the development of different TTCN-3 test suites and Codec are both required in different protocol testing, which increases the burden on development engineers, reduces the efficiency of the development of testing tools, and hinders the promotion and application of TTCN-3 protocol testing.The idea of TTCN-3 universal decoder supporting different types of protocol is proposed in this thesis, which is a research-oriented beneficial attempt for TTCN-3 protocol testing. One innovation of this thesis is the study and design of format definition file of different protocol types, the other innovation is the design and implementation of universal decoder model. This thesis explored a new way with practical application value in TTCN-3 protocol test, which will promote the development of TTCN-3 protocol test standard.The TTCN-3 standard is introduced in detail firstly. And then the analysis of every functional modules of TTCN-3 test system and the relation between TE and Codec are presented. Based on the above theory, the idea of universal decoder is proposed, the format definition file of different protocol types is designed in detail, and the universal decoder model is constructed and implemented. Universal decoder realizes the automatic decoding of different protocol types by reading format definition file and analyzing the format regulation. Finally, the verification results of the protocol testing, summary and future work are presented.