For the purposes of the present document, the terms given in TR 21.905 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905. LCS secured user plane connection: User plane connection information: For the purposes of the present document, the following terms and definitions given in TS 23.501 apply:

For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905. FQDN LCS LCS-UP LCS-UPP LMF LPP OMA SUPL TLS UPP-CM UPP-CMI

The user plane location services protocols described in the present document provide signalling connectivity between UE and LMF, LCS client or AF, for 5GS. Main functions of user plane LCS protocols are:

• support of management of an LCS secured user plane connection for user plane positioning; and
• user plane transport procedures to provide a transport of LPP messages and location supplementary services messages.

For the support of the above functions, the following procedures are supplied within this specification:

• elementary procedures for user plane positioning connection management, UPP-CM, in clause 6; and
• elementary procedures for location services user plane protocol, LCS-UPP, in clause 7.

Security, including ciphering and integrity protection, is provided by lower layers from a user plane location services protocol perspective (see TS 24.501 for UPP-CM and clause 4.3 for LCS-UPP). Co-existence of user plane location solutions is described in clause 5. The UPP-CM and LCS-UPP for 5GS follow the protocol architecture model for layer 3 as described in TS 24.007.

After a successful PDU session establishment providing user plane connectivity, an LCS secured user plane connection between the UE and the LMF for LCS-UPP is protected using a TLS based mechanism as described in TS 33.501 Annex Q.2.

The user plane location solution as described in the present specification, i.e. LCS-UPP, may co-exist with other user plane location solutions such as OMA SUPL. The use of OMA SUPL in a 3GPP network is described in TS 38.305 and TS 23.271. For UEs supporting another user plane location solution in addition to LCS-UPP, the following indications and parameters can be used to control which user plane location solution is used for such UEs:

1. LCS-UPP in NAS 5GMM capability IE (see TS 24.501);
2. SUPL in NAS 5GMM capability IE (see TS 24.501);
3. LCS-UPP in NAS 5GS network feature support IE (see TS 24.501); and
4. SUPL in NAS 5GS network feature support IE (see TS 24.501).

UEs supporting one or more user plane location solution(s) shall indicate its supported user plane location solution(s) to the network using the LCS-UPP bit, the SUPL bit or both in the 5GMM capability IE during the initial registration procedure and the mobility registration update procedure as described in TS 24.501. If the UE supports LCS-UPP, SUPL or both, the network shall indicate support of user plane location solution(s) to the UE using LCS-UPP bit, the SUPL bit or both in the 5GS network feature support IE during the initial registration procedure and the mobility registration update procedure as described in TS 24.501. The user plane location solution(s) indicated as supported by the network to the UE is selected based on network supported solutions, UE supported solutions and operator policy. After the UE receives the indication of the supported user plane location solution(s) by the network, and when needed, a user plane location solution supported by both the UE and the network can be initiated and used.