This Recommendation briefly describes the various components which make up the AAL functions necessary to support signalling (SAAL). It is intended to serve as a guide to all other Recommendations required by a user for the implementation of an AAL for the purpose of signalling.
The ATM adaptation layer (AAL) is defined as enhancing the services provided by the ATM layer to support the functions required by the next higher layer. Different AALs support various protocols to suit the different needs of a range of AAL service users. One particular type of AAL service user is the signalling entity wishing to communicate with a peer entity. The SAAL comprises AAL functions necessary to support such a signalling entity.