The “Guidelines for implementing a Signalling System No. 7 network” Handbook is intended to give the reader an overview of the elements necessary to evaluate the design, implementation and maintenance aspects of an SS No. 7 network. The Handbook is also offered to assist the reader in understanding criteria which impacts the decision to utilize SS No. 7 capabilities – particularly as they relate to cost/benefit analysis of such a decision.

The purpose of this Chapter is to give guidance to the Administration, in respect of the network requirements mentioned by CCITT Recommendations, and also the basic principles and main elements which have to be taken into account when designing an SS No. 7 network and dimensioning it.

Signalling System (SS) No. 7 is a modular signalling system with the Recommendations written in such a way that new applications of the system can be specified later on. Some of the Recommendations such as TUP (Telephone User Part) and much of the MTP (Message Transfer Part) are now considered stable. A number of different applications are currently emerging, some of which have more stable Recommendations than others. In addition, further consideration is being given to Recommendations for testing, performance monitoring, and other Operational, Administrative and Maintenance (OA&mediaamp;M) functions.