User Adaptation (UA) Layers The User Adaptation (UA) layers encapsulate different SCN signaling protocols for transport over an IP network using SCTP. While each UA layer is unique in terms of the encapsulation | User Adaptation UA Layers The User Adaptation UA layers encapsulate different SCN signaling protocols for transport over an IP network using SCTP. While each UA layer is unique in terms of the encapsulation because of the differences of the signaling protocols themselves following are some common features among all UA layers Support for seamless operation of the UA layer peers over an IP network. Support for the primitive interface boundary of the SCN lower layer which the UA layer replaces. For example M2UA supports the primitive interface boundary that MTP Level 2 supports. Support for the management of SCTP associations. Support for asynchronous reporting of status changes to layer management. The SigTran Working Group has defined several UA layers which include the following The MTP Level 2 User Adaptation M2UA layer is defined for the transport of MTP Level 3 messages between a SG and a MGC or IP database. The MTP Level 3 User Adaptation M3UA layer is defined for the transport of SS7 User Part messages such as ISUP SCCP and TUP between an SS7 SG and a MGC or other IP Signaling Point IPSP . The SCCP User Adaptation SUA layer is defined for the transport of SCCP User Part messages such as TCAP and RANAP from an SS7 SG to an IP-based signaling node or database or between two endpoints in the same IP network. The MTP Level 2 Peer Adaptation M2PA layer is defined for the transport of MTP Level 3 data messages over SCTP. M2PA effectively replaces MTP Level 2. It provides the ability to create an IP-based SS7 link. The ISDN User Adaptation IUA layer is defined for the transport of between an ISDN SG and a MGC. IUA supports both Primary Rate Access and Basic Rate Access lines. Each of these adaptation layers will be discussed in detail with the exception of IUA because it is beyond the scope of this book. Other proposed adaptation layers such as DPNSS DASS2 DUA 144 UA and V52UA 145 UA are being worked on in the SigTran Working Group however like IUA those .
