7.5.2 Terminating Identification Presentation (TIP) and Terminating Identification Restriction (TIR)

29.1633GPPInterworking between the IP Multimedia (IM) Core Network (CN) subsystem and Circuit Switched (CS) networksTS

7.5.2.1 General

The protocol specification of the Terminating Identification Presentation and Terminating Identification Restriction supplementary services is described in 3GPP TS 24.608 [64].

The procedures for mapping of the connected number described within clause 7.4.2 shall apply.

7.5.2.2 Interworking at the O-MGCF

For the mapping of IAM to the INVITE request:

If an Optional forward call indicators parameter in the IAM is received where the bit H Connected line identity request indicator is set to "requested", then the option tag "from-change" shall be add to the Supported header field. See table 7.5.2.2.1.

Table 7.5.2.2.1: Mapping of ISUP IAM to SIP INVITE request

ISUP Parameter

Derived value of parameter field

Source SIP header field and component

Source Component value

Optional forward call indicator

Connected line identity request indicator is set to "requested"

Supported

"from-change"

NOTE: The presence of "from-change" enables the reception of Generic Number with Number qualifier parameter field set to additional connected, if available. As per 3GPP TS 24.608 [64] the presence of "from-change" tag is not a criterion for TIP service.

If a provisional or final response including the option tag "from-change" is received, then the O-MGCF shall:

– if a 200 (OK) response to the INVITE request is received, start timer TTIR1; and

– store the 200 (OK) response, without interworking it.

Otherwise the 200 (OK) response (to the INVITE request) shall be mapped as described in clause 7.2.3.2.7a.

If an UPDATE request is received containing a changed From header field before the timer TTIR1 expired, then the O‑MGCF shall:

– stop timer TTIR1;

– map the From header field received in the UPDATE request to the Generic number in the ANM as shown in table 7.5.2.2.2 and table 7.5.2.2.3;

– if the UPDATE request includes a P-Asserted-Identity header field that is different from the one within the stored 200 (OK) response, the latest received P-Asserted-Identity header field shall be mapped to the connected number as described table 24; and

– map the parameters needed to be mapped of the stored 200 (OK) response to an ANM as described in clause 7.4.2.2.3, modified by the changed mapping steps of the From and P-Asserted-Identity header fields.

When TTIR1 expires, then the stored 200 (OK) response (to the INVITE request) response shall be mapped as described in clause 7.4.2.2.3.

Table 7.5.2.2.2: Mapping of SIP UPDATE request to ISUP ANM/CON

ANM/CON

UPDATE

Generic number

From header field

Table 7.5.2.2.3: Mapping of SIP From header field to ISUP Generic Number
("additional connected number") parameter

Source SIP header field and component

Source component value

Generic Number parameter field

Derived value of parameter field

Number Qualifier Indicator

"additional connected number"

From, userinfo component of URI assumed to be in form
"+" CC + NDC + SN

CC

Nature of Address Indicator

If CC is equal to the country code of the country where I‑MGCF is located AND the next ISUP node is located in the same country, then set to "national (significant) number" else set to "international number"

Number Incomplete Indicator

"complete"

Numbering Plan Indicator

"ISDN (Telephony) numbering plan (Recommendation E.164)"

Privacy, priv‑value component

Privacy header field absent

Address Presentation Restricted Indicator (APRI)

"presentation allowed"

"none"

"presentation allowed"

"header"

"presentation allowed"

"user"

"presentation restricted"

"id"

"presentation allowed"

Screening Indicator

"user provided, not verified"

From, userinfo component assumed to be in form
"+" CC + NDC + SN

CC, NDC, SN

Address Signals

If NOA is "national (significant) number" then set to

NDC + SN.

If NOA is "international number"

then set to CC + NDC + SN

7.5.2.3 Interworking at the I-MGCF

For the mapping of INVITE request to IAM:

– the bit H Connected line identity request indicator of the Optional forward call indicators parameter in the IAM shall be set to "requested".

Table 7.5.2.3.1: Void

If a received ISUP ANM includes an ISUP Generic Number ("additional connected number") parameter, then the
I-MGCF shall send a 200 (OK) response (to the INVITE request) including an option tag "from-change" If the initial INVITE was received and the Supported header field contains the "from-change" tag, the 200 (OK) response is followed by an UPDATE request, containing the "additional connected number" copied into the From header field as shown in table 7.5.2.3.2.

The To header field of the UPDATE request is derived from the P-Asserted-Identity header field received within the initial INVITE request.

Table 7.5.2.3.2: Mapping of ANM Generic Number ("additional connected number")
to SIP From header field in a SIP UPDATE request

ISUP Parameter/field

Value

SIP component

Value

Generic Number

Number Qualifier Indicator

"additional connected number"

From header field

display‑name (optional) and addr‑spec

Nature of Address Indicator

"national (significant) number"

Addr‑spec

Add "+" CC (of the country where the IWU is located) to Generic Number Address Signals then map to user portion of URI scheme used

"international number"

Map complete Generic Number Address Signals used prefixed with a "+" to user portion of URI scheme used

Address Presentation restriction indicator (APRI)

"presentation allowed"

No Privacy header field or not "user"

"presentation restricted"

"user"

Address Signals

if NOA is "national (significant) number" then the format of the address signals is:

NDC + SN

If NOA is "international number"

then the format of the address signals is:

CC + NDC + SN

Display‑name (optional)

display‑name shall be mapped from Address Signals, if network policy allows it

Addr‑spec

"+" CC NDC SN mapped to user portion of URI scheme used

A received connected number in an ANM shall be mapped to the P-Asserted-Identity header field as shown in table 21 of the UPDATE request.

7.5.2.4 Timer

Table 7.5.2.4.1 TIR timer definition

Symbol

Timeout
value

Cause for initiation

Normal termination

At expiry

TTIR1

100 – 2000 milliseconds (default 100 milliseconds)

On receipt of provisional or final response including the option tag "from-change"

At the receipt of an UPDATE

map the received 200OK to an ANM