The defines textual conventions used by to manage devices related to the SS7 network. The relevant ITU documents describing this technology is the ITU Q series, including ITU Q.700: Introduction to CCITT Signalling System No. 7 and ITU Q.701 Functional description of the message transfer part (MTP) of Signalling System No. 7. Abbreviations: CDPA - Called Party Point Code CGPA - Calling Party Point Code CLLI - Common Language Location Codes CR - Connection Request message CREF - Connection Refusal message DPC - Destination Point Code ERR - Error message GTA - Global Title Address GTI - Global Title Indicator GTT - Global Title Translation LUDT - long unitdata message LUDTS - long unitdata service message M2PA - MTP2 Peer-to-Peer Adaptation Layer M3UA - MTP3-User Adaptation MAP - Mated Application Table MSU - Message Signal Unit MTP - Message Transport Protocol MTP2 - Layer 2 of Message Transport Protocol MTP3 - Layer 3 of Message Transport Protocol NAI - Nature of Address Indicator NP - Numbering Plan NTT - The Japanese Nippon Telephone & Telegraph OPC - Originating Point Code PC - Point Code RTN - Route Table Name RSR - Reset Request message SCCP - Signalling Connection Control Part SCTP - Stream Transmission Protocol(RFC 2960) SI - Signalling Indicator SP - Signalling Point SLC - Signalling Link Code SLS - Signalling Link Selector SSN - Subsystem Number SUA - SCCP-User Adaptation TFR - Transfer Restricted messages TT - Title Translation TTC - The Japanese Telecommunications Technology Committee UDT - unitdata message UDTS - unitdata service message XUDT - extended unitdata message XUDTS - extended unitdata service message