5.1.9 Charging support for Network provided Location information

32.2603GPPCharging managementIP Multimedia Subsystem (IMS) chargingRelease 17Telecommunication managementTS

5.1.9.1 User location retrieval by IMS Nodes

The Network provided Location information (NetLoc) is described in the TS 23.228 [201] and for emergency service request using PCC-based solutions for the UE location in mobile networks in TS 23.167 [212].
In some scenarios, an AS can also detect emergency service and obtain the UE location using HSS-based solutions in TS 23.167 [212].

Based on operator policies and the availability of the user location information and/or UE Time Zone from the access network, the solution ensures that relevant SIP messages contain the correct or up to date information about the user location information, and/or UE Time Zone provided by the access network and currently used by the UE.

For the 3GPP and non-3GPP accesses, the P‑CSCF can retrieve user location information and/or UE Time Zone related to the access network currently used by the UE using PCC mechanisms, as specified in TS 23.203 [213] , TS 23.503 [221] and TS 29.214 [214] . In some scenarios, an AS can also obtain location information using HSS-based solutions in TS 29.328 [215].

For fixed networks, the P-CSCF is aware of the network provided location information through signalling with the NASS.

5.1.9.2 User location information content

As specified in TS 24.229 [204], clause 7.2A.4.3, the network provided location information is transported in the SIP P-Access-Network-Info header with an "np" parameter and indicates details of where the UE is currently located as defined in TS 23.228 [214].

For trusted WLAN access, the SIP P-Access-Network-Info header includes the BSSID, and as specified in TS 23.228 [201] Annex T, a Geographical Identifier, if generated by the P-CSCF or AS based on the retrieved Access Network Information.

For untrusted WLAN access, the SIP P-Access-Network-Info header includes the BSSID, and as specified in TS 23.228 [201] Annex V, UE local IP address, ePDG IP Address, and the TCP source port or UDP source port used by the UE to establish the IKEv2 tunnel with the ePDG.

For 3GPP accesses, the SIP P-Access-Network-Info header includes the SAI, TAI, RAI, CGI, ECGI, and NCGI.

NOTE: When NR is accessed by the UE via Dual Connectivity scenario (i.e. option 3a/x) specified TS 23.401 [222] clause 4.3.2a, the user location is retrieved from EPC, i.e. NCGI is not applicable.

For other accesses, the SIP P-Access-Network-Info header includes specific user location information detailed in TS 24.229 [204], clause 7.2A.4.3.

5.1.9.3 User location Access charging

In the defined CDRs, the network provided location information available when the CDR is opened, for 3GPP accesses is directly available in the User Location Info field and also available in the Access Network Information or Additional Access Network Information fields. For non-3GPP accesses, the network provided location information available when the CDR is opened, shall be available in either the Access Network Information or Additional Access Network Information fields

NOTE 1: In a node that receives two"P-Access-Network-Info" headers, in Rel-11, the operator determined which "P-Access-Network-Info" header (i.e., network-provided or UE-provided) would be included in the Access Network Information field. For backward compatibility, for an operator that deployed the Rel-11 capability the other "P-Access-Network-Info" header should be included in the Additional Access Network Information field.

NOTE 2: In a node that receives two "P-Access-Network-Info" headers for an operator first deploying this capability in Rel-12, it is recommended that the network-provided "P-Access-Network-Info" header be included in the Access Network Information field and a UE-provided "P-Access-Network-Info" header be included in the Additional Access Network Information field.