The Study Of Mechanism Transferring SS7 Signaling In 3G Core Network Circuit Switched Domain

Universal Mobile Telecommunication System (UMTS) is compatible with the standards defined by 3GPP. Standard of Release 4 defined by 3GPP presents an IP core network. The core network(CN) contents two parts which are a Circuit Switched (CS) domain and a Packet Switched (PS) domain. The CS domain supports voice traffic, and the PS domain supports data traffic. The interfaces between CN entities, including (G)MSC VLR and HLR, are based SS7 signaling. So how to transfer SS7 signaling in IP network is a question that must be solved.Unfortunately there is not a whole framework of transferring SS7 in IP network except presenting some protocols. SS7 signaling is strict with bear of signaling. Traditional IP network can not meet the demand of transferring SS7 signaling because of it's character ------an IP network, so bear of transferring SS7 signaling in IP network must been optimized. Bear of transferring SS7 signaling in IP network consists of M3UA SCTP and IP, so the three protocols must all been optimized.In this paper, we presented methods of solving IP QoS and security through studying IP QoS and security, and summarize a method of optimizing IP. We improved Stream Control Transfer Protocol (SCTP) by modifying recovery mechanism and congestion control mechanism, and an idea of exploiting recovery mechanism of SCTP. We presented an example of implementing ASP by studying M3UA protocol. We provided two models of implementing SS7 network in IP network, and compare the two different models. We summarized methods presented above, and took into account relationship of the three protocols, so as to get a framework of transfer SS7 signaling in 3G core network CS domain.