INTERNATIONAL  TELECOMMUNICATION  UNION

		     ITU-T RECOMMENDATION SUMMARY


Rec. No. : Q.81.5

Title :	Stage 2 description for number identification supplementary 
	services

Study Group : XI - Switching and Signalling

Version : Revised

Date of adoption : 1991

Notes :	


       CONNECTED LINE IDENTIFICATION, PRESENTATION AND RESTRICTION 
				(COLP AND COLR)

Recommendation Q.81.5 defines the stage 2 of the integrated services 
digital network (ISDN) as provided by public telecommunications 
operators for the Connected Line Identification Presentation (COLP) 
and Connected Line Identification Restriction (COLR) supplementary 
services. Stage 2 identifies the functional capabilities and the 
information flows needed to support the service description. The 
stage 2 description also identifies user operations not directly 
associated with a call (see Recommendation I.130).

Recommendation Q.81.5 is defined according to the methodology 
specified in Recommendation Q.65.

Recommendation Q.81.5 does not formally describe the relation between 
these supplementary services and the basic call but, where possible, 
this information is included for guidance.

In addition, Recommendation Q.81.5 does not specify the requirements 
where the service is provided to the user via a private ISDN. 
Recommendation Q.81.5 does not specify the requirements for the 
allocation of defined functional entities within a private ISDN; it 
does however define which functional entities may be allocated to a 
private ISDN.

Recommendation Q.81.5 does not specify the additional requirements 
where the service is provided to the user via a telecommunications 
network that is not an ISDN.

The COLP supplementary service provides the calling party with the 
possibility to receive identification of the connected party.

The COLR supplementary service enables the connected party to prevent 
presentation of its ISDN number to the calling party.

The COLP and COLR supplementary services are applicable to all 
telecommunication services.

Recommendation Q.81.5 is applicable to the stage 3 standards for the 
ISDN COLP and COLR supplementary services. The term "stage 3" is 
defined in Recommendation I.130.



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