Name: UNI-SSCF

Module: usscf


GENERAL

The ATM Adaptation Layer used to support signalling (SAAL) is a combination
of two sublayers: a common part and service specific part. The common part
is defined in clause 6/I.363 [1]. The service specific part is further
split into two parts: the Service Specific Coordination Function (SSCF)
and the Service Specific Connection Oriented Protocol (SSCOP).

The purpose of the SAAL is to convey information between layer 3 entities
across the UNI and NNI using Asynchronous Transfer Mode (ATM) virtual
channels. The purpose of the SSCF at UNI is to map the UNI layer 3
protocol (Recommendation [5] Q.2931) to the service of the next lower layer.

Recommendation Q.2100 [2] provides an overview of this strucutre.
Recommendation Q.2130 [4] specifies the SSCF at UNI implemented in this
usscf module. Recommendation Q.2110 [3] specifies the SSCOP. 


REFERENCES

[1]	ITU-T Recommendation I.363, B-ISDN ATM Adaptation Layer (AAL)
	specification.

[2]	ITU-T Recommendation Q.2100, B-ISDN signalling ATM Adaptation Layer
	(SAAL) overview description.

[3]	ITU-T Recommendation Q.2110, B-ISDN Adaptation Layer - Service
	Specific Connection Oriented Protocol (SSCOP).

[4]	ITU-T Recommendation Q.2130, B-ISDN signalling ATM Adaptation Layer -
	Service Specific Coordination Function for support of signalling
	at the user-network interface (SSCF at UNI).

[5]	ITU-T Recommendation Q.2931, B-ISDN - Digital Subscriber Signalling
	System No. 2 (DSS2) - User network infterface layer 3 specification
	for basic call/connection control.