The study of the interconnection of GSM mobile communication system over IP based network

We propose a protocol to interconnect the GSM mobile communication networks and PSTN through an IP based backbone. The basic functions of mobile communication such as call setup, call recovery, and handover together with its further applications such as conference calls are taken into account. Not only establishment and closing of a conference call are discussed, but also the recovery procedures due to the failure of handover are also considered. Different feasible interconnection types are also studied. There are several possible connecting topologies, that can be divided into two categories: (1) MSC of the same operator are connected in a traditional architecture; only the GMSC of different operators are connected via the IP network; (2) all MSC are liked with the IP network. The mechanisms suitable for the connection are studied