4 Connected line identification restriction (COLR)

03.813GPPLine Identification supplementary servicesStage 2TS

4.1 Handling of connected line identification restriction

4.1.1 General

If the terminating party has connected line identification restriction provisioned and it is impossible to indicate to the originating network (due to interworking) that the number should not be presented to the originating party, the connected line identity shall not be delivered to the originating network.

4.1.2 Interrogation

Status check

The mobile subscriber can request the status of the supplementary service and be informed if the service is provided to him/her. This procedure is illustrated in figure 4.1.

Figure 4.1: Interrogation of connected line identification restriction

4.2 Functions and information flows

The following Mobile Additional Functions have been identified for the PLMN:

MAF040

Determination of the connected line identification restriction subscription

The ability of a PLMN component to determine whether the supplementary service is provisioned for the mobile subscriber. See figure 4.2.

Location: VLR.

MAF041

Determination of the connected party number for offering to the calling party

The ability of a PLMN component to determine and to forward the connected line identity and related indications to the calling party. See figure 4.3.

Location: terminating MSC.

The information flow is shown in figures 4.4.

Figure 4.2: MAF040 Determination of connected line identification restriction subscription
(VLR)

Figure 4.3: MAF041 Determination of the presentation indicator

NOTE: OR1: COLR provisioned Y: yes N: no OR2: Presentation Indicator Value a: allowed b: restricted OR3: Override category **: A subaddress may be received from the MS info: information SI: screening indicator req: request PI: presentation indicator ack: acknowledge LI: line identity

Figure 4.4: Information flow for connected line identification restriction:
mobile station or fixed terminal to mobile station

4.3 Information stored in the HLR

COLR may have the following logical states (refer to GSM 03.11 for an explanation of the notation):

Provisioning State Registration State Activation State HLR Induction State

(Not Provisioned, Not Applicable, Not Active, Not Induced)

(Provisioned, Not Applicable, Active and Operative, Not Induced)

The HLR shall store the logical state of COLR (which shall be one of the valid states listed above) on a per subscriber basis.

4.4 State transition model

The following figure shows the successful cases of transition between the applicable logical states of COLR. The state changes are caused by actions of the service provider.

Note that error cases are not shown in the diagram as they normally do not cause a state change. Additionally, some successful requests may not cause a state change. Hence they are not shown in the diagram.

Figure 4.5: State transition model for COLR

4.5 Transfer of information from HLR to VLR

When the subscriber registers on a VLR, the HLR shall send that VLR information about the logical state of COLR.

If the logical state of COLR is changed while a subscriber is registered on a VLR then the HLR shall inform the VLR of the new logical state of COLR.

4.6 Information stored in the VLR

For COLR, the VLR shall store the service state information received from the HLR.

4.7 Handover

Handover will have no impact on the control procedures and the operation of the service.

4.8 Interworking

The VPLMN needs to distinguish three cases in order to meet data privacy requirements in an environment where support of COLP and COLR is optional:

a) the HPLMN supports COLR, and COLR is provisioned for the subscriber;

b) the HPLMN supports COLR, but COLR is not provisioned for the subscriber;

c) the HPLMN does not support COLR.

In case a) the VPLMN must apply the COLR subscription as indicated by the data sent by the HPLMN.

In case b) the VPLMN must not apply COLR.

In case c) the VPLMN must apply an implicit COLR subscription.

To allow the VPLMN to make this distinction, the HLR and VLR behave as follows:

‑ If the HLR supports COLR, but COLR is not provisioned for the subscriber, the HLR shall inform the VLR that COLR is not provisioned.

‑ If the VLR supports COLR, but the HLR does not support COLR, the VLR shall behave in the same way as if COLR was provisioned for the subscriber, i.e. the connected line identity shall not be displayed to the calling subscriber unless the calling subscriber has COLR override capability. When interrogating the service status the subscriber shall be informed that COLR is provided to him and is active.

Annex A (informative):
Change Request History

Status
of
Technical Specification GSM 03.81

Date Version Remarks

No phase 1 version

January 1992 version 4.0.0 TS approved by SMG#01

June 1992 version 4.0.1 CR 03.81‑01 (category D) approved by SMG#03

January 1993 version 4.0.2 CR 03.81‑02 (category D) approved by SMG#05
CR 03.81‑03 (category D)

April 1993 version 4.1.0 CR 03.81‑04 rev 3 (category C) approved by SMG#06
Reference to MCI removed
TS frozen for phase 2 by SMG#06

October 1993 version 4.1.1 TS changed to draft prETS 300 542

January 1994 version 4.2.0 CR 03.81‑06 rev 1 (category F) approved by SMG#09

April 1994 version 4.3.0 CR 03.81‑05 rev 4 (category F) approved by SMG#10
CR 03.81‑08 (category F)

July 1994 version 4.4.0 CR 03.81‑07 rev 2 (category F) approved by SMG#11

October 1994 version 4.5.0 CR 03.81‑10 rev 1 (category F) approved by SMG#12
CR 03.81‑11 rev 1 (category F)
CR 03.81‑12 (category F)
CR 03.81‑13 rev 1 (category F)
CR 03.81‑14 (category F)
TS changed to final draft prETS 300 542

January 1995 version 4.5.1 TS changed to ETS 300 542 First edition

June 1996 version 4.6.0 CR 03.81‑A003 rev 1 (category F) approved by SMG#19

December 1996 version 5.0.0 ETS changed to GTS for Release 96

December 1997 version 5.1.0 CR 03.81-A005 rev 1 (category A) approved by SMG#24
WI: CAMEL Phase 1:
Section 0.2.1.1 and 0.2.1.2: Definition of additional line identity
Figs 1.3/1.8: Update of MAF002 and Information flow for CLIP
Figs 3.3/3.5: Update of MAF006 and Information flow for COLP

June 1998 version 5.2.0 CR 03.81-A007 (category F) approved by SMG#26
CR 03.81-A009 rev 1 (category F) (TEI)

January 1999 version 6.0.0 Release 1997 version

May 1999 version 7.0.0 CR 03.81 A010r4 (cat. B) approved by SMG#28 June

June 1999 version 7.0.1 Publication of version 7.0.1

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