Signalling System Number 7 (SS7) – Message Transfer Part (MTP)
|Publication Date:||1 July 2005|
SCOPE, PURPOSE, & APPLICATION
The overall objective of the SS7 Message Transfer Part (MTP) is to provide an internationally standardized general purpose common channel signalling system that provides a reliable means of transfer of information in correct sequence and without loss or duplication.
The signalling system is optimized for operation over 56 or 64 kbit/s digital channels. The signalling system is also optimized for 1.536 Mbit/s data rate links to accommodate the growth of SS7 traffic. For Asynchronous Transfer Mode (ATM) based transmission, the signalling system is optimized for operation at 64 kilobits/s and higher. The system is suitable for use on point-to-point terrestrial and satellite links.
It does not include the special features required for use in point-to-multipoint operation but can , if required, be extended to cover such an application.
The signalling system uses signalling links for transfer of signalling messages between exchanges or other nodes in the telecommunication network served by the system. Arrangements are provided to ensure reliable transfer of signalling information in the presence of transmission disturbances or network failures. These include error detection and correction on each signalling link. The system is normally applied with redundancy of signalling links, and it includes functions for automatic diversion of signalling traffic to alternative paths in case of link failures. The capacity and reliability for signalling may thus be dimensioned by provision of a multiplicity of signalling links according to the requirements of each application.