ITU Q.1912.5C:2008 Interworking Between Session Initiation Protocol (sip) And Bearer Independent Call Control Protocol (bicc) Or Isdn User Part (isup): Test Suite Structure And Test Purposes (tss&tp) For Profile A And B Describes the test suite structure and test purposes (TSS&TP) for the interworking between session initiation protocol (SIP) and bearer independent call control protocol or between SIP and ISDN user p