scope:

This standard defines the stage one of the pan-European integrated Services Digital Network (ISDN) as provided by European public telecommunications operators for the circuit-mode 64 kbit/s 8 kHz structured bearer service category usable for 3.1 kHz audio information transfer. Stage one is an overall service description from the user's point of view (see CCITT Recommendation I.130 [1]), but does not deal with the details of the human interface itself.

This standard defines the interworking requirements of private ISDNs with the public ISDN.

In addition this standard specifies the base functionality where the service is provided to the user via a private ISDN.

This standard does not specify the additional requirements where the service is provided to the user via a telecommunications network that is not an ISDN but does include interworking requirements of other networks with the public ISDN.

Charging principles are outside the scope of this standard.

The values of the general attributes are outside the scope of this standard.

The circuit-mode 64 kbit/s 8 kHz structured bearer service category usable for 3.1 kHz audio information transfer corresponds to the service which is currently offered in the PSTN. This bearer service category provides for the transfer of speech and of 3.1 kHz bandwidth audio information such as voice band data via moderns, facsimile group 1, 2 and 3 information.

This digital signal at the coincident S and T reference point (see CCITT Recommendation I.411 [2]) conforms to CCITT Recommendation Rec. G. 711 [3] (A-law).

The remainder of the definition has been moved to clause 5 in order to shorten the scope, and to remove the requirements contained here.