1 Calling line identification presentation (CLIP)

23.0813GPPLine Identification supplementary servicesRelease 17Stage 2TS

1.1 Handling of calling line identification presentation

1.1.1 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 1.1.

Figure 1.1: Interrogation of calling line identification presentation

1.2 Functions and information flows

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

MAF001

Determination of the calling line identification presentation subscription

The ability of a PLMN component to determine whether the sup­plementary service is provisioned for the mobile subscriber. See figure 1.2.

Location: VLR.

MAF002

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

The ability of a PLMN component to determine and to forward the calling line identity and related indications to the called party. See figure 1.3.

Location: destination MSC.

The information flow is shown in figure 1.9.

Figure 1.2: MAF001 Determination of calling line identification presentation subscription
(VLR)

Figure 1.3: MAF002 Determination of the information for offering to the called party
(destination MSC)

Figure 1.4: Procedure Cause_of_no_CLI

Figure 1.5: Addition of line identification information to Send Routeing Info message.

Figure 1.6: Addition of line identification information to Provide Roaming Number message.

Figure 1.7: Storing of Line Identification in destination VLR

Figure 1.8: Addition of line identification information to Complete Call/Process Call Waiting message.

Figure 1.9: Information flow for calling line identification presentation:
mobile station or fixed terminal to mobile station

NOTE:
**: A subaddress may be received from the originating MS or the TE
info: information SI: screening indicator aSI: additional screening indicator
req: request PI: presentation indicator CoNC: cause of no CLI
aPI: additional presentation indicator
ack: acknowledge LI: line identity aLI: additional line identity

NOTE: For mapping rules of CLI parameters refer to Annex A.

1.2.1 Optional capability to carry calling line identification

When GMSC is performing Send Routing Info query it may pass calling line identification to the HLRb. The calling line identification shall be in international format. If the HLRb receives calling line identification within Send Routing Info it may pass unmodified calling line identification within Provide Roaming Number to the VLRb. HLR shall not pass calling line identification in the HPLMN nor in the case where sending of the CLI information is explicitly denied to the destination network..

If MSCb receives calling line identification only from signalling it shall use that parameter for presentation purposes i.e. normal handling as described in the previous clause applies.

If MSCb receives Cause of no CLI from signalling it shall be sent to the VLRb by Send Info for Incoming Call query.

If MSCb receives calling line identification and/or Cause of no CLI from VLRb and it supports the feature it shall use that parameter for presentation purposes. In this case calling line identification is stored in the VLRb and when the set-up message is processed the handling described in the previous clause is done using the stored calling line identification.

1.2.2 Information elements used in the messages

Table 1.2.2.1: Information elements used in messages

Information Element	Logical Information element name	Information element Required	Information element description
Calling Party Number	SI PI LI	M M M	Calling Party Number contains screening indicator (SI), presentation indicator (PI) and line identity (LI) as mandatory information.
Generic Number	aSI aPI aLI	M M M	Generic Number contains additional screening indicator (aSI), additional presentation indicator (aPI) and additional line identity (aLI) as mandatory information.
Cause of no CLI	unavailable reject by user interaction with other service coin line/payphone	M M M M	Cause of no CLI contains detailed Cause of no CLI (unavailable, reject by user, interaction with other service, coin line/payphone) as mandatory information.

1.2.3 Parameters in Send Routeing Info and Provide Roaming Number for CLI

Table 1.2.3.1: Messages between GMSC and HLR

Message	Message sender	Information element name	Information element Required	Information element description
Send Routeing Info	GMSC	– Calling Party Number Generic Number	– C C	Refer to 3GPP TS 23.018. In addition: The information element is present if GMSC received calling party number from originating network; otherwise it shall be absent. The information element is present if GMSC received additional calling party number from originating network or from gsmSCF because of a CAMEL service; otherwise it shall be absent.

Table 1.2.3.2: Messages between HLR and VLR

Message	Message sender	Information element name	Information element Required	Information element description
Provide Roaming Number	HLR	– Calling Party Number Generic Number	– C C	Refer to 3GPP TS 23.018. In addition: The information element is present if HLR received calling party number from GMSC and MS B is outside of home country; otherwise it shall be absent. The information element is present if HLR received additional calling party number from GMSC and MS B is outside of home country; otherwise it shall be absent.

1.2.4 Messages between MSC and VLR in destination network

Table 1.2.4.1: Messages between MSC and VLR

Message	Message sender	Information element name	Information element Required	Information element description
Complete Call	VLR	– Calling Party Number Generic Number Cause of no CLI	– C C C	Refer to 3GPP TS 23.018. In addition: The information element is present if it is stored in VLR; otherwise it shall be absent. The information element is present if it is stored in VLR; otherwise it shall be absent. The information element is present if it is stored in VLR; otherwise it shall be absent.
Process Call Waiting	VLR	– Calling Party Number Generic Number Cause of no CLI	– C C C	Refer to 3GPP TS 23.018. In addition: The information element is present if it is stored in VLR; otherwise it shall be absent. The information element is present if it is stored in VLR; otherwise it shall be absent. The information element is present if it is stored in VLR; otherwise it shall be absent.
Send Info for Incoming Call	MSC	– Cause of no CLI	– C	Refer to 3GPP TS 23.018. In addition: The information element is present if MSC received Cause of no CLI; otherwise it shall be absent.

1.3 Information stored in the HLR

CLIP may have the following logical states (refer to 3GPP TS 23.011 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 CLIP (which shall be one of the valid states listed above) on a per subscriber basis.

The HLR shall also store the subscription option "override category" on a per subscriber basis.

This parameter takes one of the following values:

1. yes;

2. no.

1.4 State transition model

The following figure shows the successful cases of transition between the applicable logical states of CLIP. 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 1.9: State transition model for CLIP

1.5 Transfer of information from HLR to VLR

If the provisioning state for CLIP is "Provisioned" then, when the subscriber registers on a VLR, the HLR shall send that VLR information about the logical state of CLIP. The HLR shall send the override category if the VLR is in the HPLMN country. The HLR may send the override category if the VLR is outside the HPLMN country.

If the logical state of CLIP or the override category is changed while a subscriber is registered on a VLR then the HLR shall inform the VLR of the new logical state of CLIP. If the override category is changed and the provisioning state of CLIP is "Provisioned" then the HLR shall inform the VLR about the new override category when the VLR is in the HPLMN country. The HLR may inform the VLR about the new override category when the VLR is outside the HPLMN country.

1.6 Information stored in the VLR

For CLIP, the VLR shall store the service state information and override category received from the HLR.

If not received from the HLR (case of roaming outside the HPLMN country), the override category shall be set to the default value "no".

1.7 Handover

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

1.8 Interactions with other supplementary services

See 3GPP TS 22.081 [4] clause 1.6.