Reliability improvements of SS7 signaling protocol architecture using ATM technology

In this paper, we consider the link fault tolerance and error correction mechanisms of conventional signaling protocols to provide reliable services in a mobile multimedia telecommunication network based on ATM (asynchronous transfer mode) technology. Also, we propose efficient and optimized reliability support methods based on MTP-3 and SAAL layer for the ATM based IMT2000 system and WATM network. The first method is an end-to-end link fault detection and traffic rerouting method using the fast detection and rerouting scheme of SAAL as well as the reliable retransmission method of MTP-3. The second methodology is localized fault detection and rerouting between the IWF (inter-working function) and ATM network. By using these methods, the wormhole problem in the ATM network can be avoided between IWFs and ATM switches without notification of end-stations. Besides, we evaluate the performance of the proposed method through computer simulation. According to simulation results,the proposed signaling architecture shows efficient and fast fault restoration characteristics compared to the conventional MTP-3/3b based network. The functional signaling protocol stack and network architecture of the proposed fast rerouting mechanism provide reliable and efficient restoration performance in view of interworking between the SS7 based IMT2000 system and ATM networks.