SIGTRAN : Signaling over IP -- a step closer to an all-IP network

Sammanfattning: The mass popularization of telecommunication services in recent years have resulted in a heavily loaded signaling network. The Signaling System number 7 (SS7) is used in fixed and wireless networks and is needed for call control and services such as caller ID, roaming, and for sending SMS. The traditional SS7 networks are expensive to lease and to expand, hence a new suite of protocols have been designed to carry signaling messages over IP. This suite contains a transport protocol called Stream Control Transmission Protocol (SCTP) and various user adaptation layer protocols such as M2PA, M2UA, M3UA, and SUA. To transport the highly loss and delay sensitive signaling messages over IP, it is mandatory that the transport protocol meets the high performance requirements of SS7. Not before the IP-solution has been tested in detail, will it replace significant parts of the national telephone network. In this thesis, the failover duration in the case of link failure was tested using the feature of SCTP called multi-homing. The results suggest that carrying SS7 signaling traffic over IP is possible, since the failover duration does not exceed the required limit.