Sip And Bicc / Isup Interworking

A very important part of NGN developing is network evolving and network merging. It includes PSTN evolved into NGN and PSTN merging with mobile network. The significant point to implement the network merging is signalling interworking within networks.To implement the signalling interworking between BICC/ISUP and SIP in NGN, IETF and ITU-T provide specifications and recommendations, respectively. IETF provides specifications RFC3372, RFC3398, RFC3204, and ITU-T provides recommendation Q.1912.5 and technical report TRQ.2815.This paper generally introduces the specifications and applications of SIP and BICC/ISUP firstly. Subsequently, by analyzing the specifications of IETF and ITU-T, the technical requirements and methods to implement the signalling interworking between SIP and BICC or ISUP are researched in theoretic. At last, as a guide for implementing interworking between SIP and BICC/ISUP in theoretic and practical, based on the recommendations provided by ITU-T, the system and module designing and implementation of Softswitch system and interworking function is presented.In this paper, under the background of a Softswitch system project that is provided by a national famous telecom supplier, the author mainly does the works as the following.Firstly, by analyzing the principles and the questions of the specifications of IETF and ITU-T, the implementation for the signalling interworking between SIP and BICC or ISUP is researched in theoretic.Secondly, the system designing and implementation for interworking in Softswitch system is presented.Thirdly, based on Q.1912.SIP, the designing and implementation for IWF module is presented.At last, SIP extension for supporting BICC/ISUP directly is analyzed based on the research and project.Based on successful using in business, the research provides an available solution and guides the developing for interworking between SIP and BICC/ISUP.