1 Calling line identification presentation (CLIP)

03.813GPPLine Identification supplementary servicesStage 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 1.8.

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: Addition of line identification information to Send Routeing Info message

Figure 1.5: Addition of line identification information to Provide Roaming Number message

Figure 1.6: Storing of Line Identification in destination VLR

Figure 1.7: Addition of line identification information to Complete Call/Process Call Waiting message

(CR A005r1)

MS/TE MSCa/LE GMSC HLRb VLRb MSCb MSbá
┌───┐ ┌───┐ ┌───┐ ┌───┐ ┌───┐ ┌──────┐ ┌──┐
│ │set-up│ │ │ │ │ │ │ │ │ │ │ │
│ ├─────>│ │ set-up │ │ │ │ │ │ │ │ │ │
│ │ ** │ ├─────────>│ │ │ │ │ │ │ │ │ │
│ │ │ │(SI+PI+LI+aSI+aLI) │ │ │ │ │ │ │ │
│ │ │ │ │ │ SRI │ │ │ │ │ │ │ │
│ │ │ │ │ │───────>│ │ │ │ │ │ │ │
│ │ │ │ │ │(SI+PI+LI+aSI+aLI) │ │ │ │ │ │
│ │ │ │ │ │ │ │ PRN │ │ │ │ │ │
│ │ │ │ │ │ │ │──────>│ │ │ │ │ │
│ │ │ │ │ │ │ │(SI+PI+LI+aSI+aLI) │ │ │ │
│ │ │ │ │ │ │ │PRN ack│ │ │ │ │ │
│ │ │ │ │ │SRI ack │ │<──────│ │ │ │ │ │
│ │ │ │ │ │<───────│ │ │ │ │ │ │ │
│ │ │ │ │ │ set-up│ │ │ │ │ │ │ │
│ │ │ │ │ │────────┼───┼───────┼───┼───────>│ │ │ │
│ │ │ │ │ │(SI+PI+LI+aSI+aLI) │ │ │ │ │ │
│ │ │ │ │ │ │ │ │ │info req│ │ │ │
│ │ │ │ │ │ │ │ │MAF│<───────┤ │ │ │
│ │ │ │ │ │ │ │ │001│ │ │ │ │
│ │ │ │ │ │ │ │ │ │info ack│ │ │ │
│ │ │ │ │ │ │ │ │ ├───────>│MAF002│ │ │
│ │ │ │ │ │ │ │ │ │ │OR1:N │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │OR1:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR2:c │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │ │ (PI) │ │
│ │ │ │ │ │ │ │ │ │ │OR1:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR2:b │ │ │
│ │ │ │ │ │ │ │ │ │ │OR3:N │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │ │ (PI) │ │
│ │ │ │ │ │ │ │ │ │ │OR1:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR2:b │ │ │
│ │ │ │ │ │ │ │ │ │ │OR3:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR4:N │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │ │(SI+PI+LI) │
│ │ │ │ │ │ │ │ │ │ │OR1:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR2:b │ │ │
│ │ │ │ │ │ │ │ │ │ │OR3:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR4:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR5:a │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │ │(SI+PI+LI) │
│ │ │ │ │ │ │ │ │ │ │OR1:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR2:b │ │ │
│ │ │ │ │ │ │ │ │ │ │OR3:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR4:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR5:b │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │ │(aSI+PI+aLI)│
│ │ │ │ │ │ │ │ │ │ │OR1:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR2:a │ │ │
│ │ │ │ │ │ │ │ │ │ │OR4:N │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │ │(SI+PI+LI) │
│ │ │ │ │ │ │ │ │ │ │OR1:Y │ │ │
│ │ │ │ │ │ │ │ │ │ │OR2:a │ │ │
│ │ │ │ │ │ │ │ │ │ │OR4:Y │ set-up │ │
│ │ │ │ │ │ │ │ │ │ │ ├────────>│ │
│ │ │ │ │ │ │ │ │ │ │ │(aSI+PI+aLI)│

NOTE: OR1: CLIP provisioned Y: yes N: no OR2: Presentation Indicator Value a: allowed b: restricted c: not available OR3: Override category OR4: additional line identity available Y: yes N: no OR5: CLI in case of override category a: LI b: aLI **: 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 ack: acknowledge LI: line identity aLI: additional line identity

Figure 1.8: Information flow for calling line identification presentation:
mobile station or fixed terminal to mobile station

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 subclause applies.

If MSCb receives calling line identification 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 setup message is processed the handling described in the previous subclause 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

aLI

M

M

Generic Number contains additional screening indicator (aSI) and additional line identity (aLI) 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 GSM 03.18.

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 calling party number from originating network; 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 GSM 03.18.

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 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

C

C

Refer to GSM 03.18.

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.

Process Call Waiting

VLR

Calling Party Number

Generic Number

C

C

Refer to GSM 03.18.

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.

1.3 Information stored in the HLR

CLIP 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 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:

‑ yes;

‑ 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.