5GS provides simultaneous integration of different access types 3GPP and non-3GPP (wireline and wireless), defined in TS 23.501. Accordingly, this enables the MC service UE to be used under both stationary and non-stationary conditions. With the convergence of multiple access technologies in 5GS, service features can be assigned agnostically without taking the access type into account for the MC service user.

With the use of 5GS, MC services shall be available via 3GPP access as well as via non-3GPP access. To enable access to the MC system, the use of the various access types shall be authorized by the 5GC. The simultaneous use of different access types (Access Traffic Steering, Switching and Splitting) is defined in TS 23.501 and its characteristics are subject to respective operators policy.

The access from 5GS to the MC service environment takes place via the Data Network (DN) in accordance with TS 23.501. A Data Network Name (DNN) as part of the 5GS user profile allows access to the Data Network with up to 8 connectivity sessions (PDU sessions) each with up to 64 communication flows (QoS flows). Different data networks require different DNNs.

For MC service UEs who only utilize 5GS, a single DNN may be used for:

• for the SIP-1 reference point;
• for the HTTP-1 reference point; and
• for the CSC-1 reference point.

The DNN shall be made available to the MC service UE either via UE (pre)configuration or via initial UE configuration on a per HPLMN and optionally also per VPLMN basis. The MC service UE may exploit secondary authentication/authorization by a DN-AAA server during the establishment of session connectivity as specified in TS 23.501 using the Extensible Authentication Protocol (EAP) to access the DN identified by the MC service DNN. If required, DN access credentials shall be made available to the MC service UE via initial MC service UE configuration on a per DNN basis. The DN connection to the DNN defined within the present subclause can be of PDU session type "IPv4", "IPv6", "IPv4v6", Ethernet or Unstructured (see TS 23.501). If a DN connection to an DNN defined within the present subclause is of type "IPv4v6" then the MC service client shall use configuration data to determine whether to use IPv4 or IPv6. For MC service UEs who utilize EPS and 5GS clause 5.2.7 of TS 23.280 applies.

In 5GS, quality of service is enforced at QoS flow level and corresponding packets are classified and marked with an identifier in accordance with TS 23.501. Every QoS flow is characterized by a QoS profile provided by the 5GC, and can be used for all connectivity types (PDU sessions) in accordance with TS 23.501. 5G QoS characteristics, standardized or non-standardized, are indicated through the 5QI value in accordance with TS 23.501. Standardized 5QI values have a one-to-one mapping to a standardized combination of 5G QoS characteristics and non-standardized 5QI values allows a dynamic assignment of QoS parameter values. The QoS parameter Allocation Retentions Priority (ARP) determines the priority level, the pre-emption capability and the pre-emption vulnerability of each QoS flow. ARP priority level defines the relative importance of a resource request to allow in deciding whether a new QoS Flow may be accepted or needs to be rejected in the case of resource limitations in accordance with TS 23.501. The use of Multicast Broadcast Services (MBS) for MC services shall apply QoS handling as determined by TS 23.247.

The selection, deployment, initiation, and termination of QoS signalling and resource allocation shall consider the QoS mechanisms described in TS 23.501, TS 23.502, TS 23.503 and TS 23.247 for MBS. MC system as well as MC service UE may share one DNN using multiple QoS flows for the settlement of MC services, application plane and signalling plane. For the transport of SIP-1 reference point signalling, the standardized 5QI value of 69 in accordance with TS 23.501 shall be used. For the transport of HTTP-1 reference point signalling, the standardized 5QI value of 8 in accordance with TS 23.501 or better shall be used. MC services shall use standardized 5QI values or may use non-standardized 5QI values in accordance with TS 23.501. When the MC system utilizes IMS services, at least one QoS flow shall be associated for IMS signalling. The generic mechanisms for interaction between QoS and session signalling applicable for the use of IMS in the 5GS context are defined in TS 23.228.

Network slicing in accordance with TS 23.501 can be used for several purposes such as to separate MC service users, UEs as well as applications in accordance with the various QoS requirements independent from 3GPP or non-3GPP access. The corresponding slice information identifies a network slice across the 5G core, access network and the UE. In accordance with TS 23.501 standardized and non-standardized slice selection information can be used.

For the use of network slicing in the MC service context, the following minimum requirements in accordance with TS 23.501 shall be considered: One network slice shall be assigned per PDU session and may benefit from a dedicated transmission resource allocation. The network slicing for MC services follows the concepts defined in TS 23.501. The Initial MC service UE configuration shall contain at least one network slice identity (S-NSSAI). Those S-NSSAIs shall be considered as part of the Default Configured S-NSSAI(s), and should be utilized by the MC service UE to form the Requested S-NSSAI(s) at registration as specified in TS 23.501. If the MC service UE requests a slice which is subject to Network Slice-Specific Authentication and Authorization, the corresponding aspects as well as the MC service UE behaviour are to be followed as described in TS 23.501, and TS 23.502. The corresponding credentials per S-NSSAI can be configured in the initial MC service UE configuration or UE (pre-)configuration. The use of network slices corresponding to non-standardized NSSAIs across PLMN boundaries requires harmonisation in order to guarantee their availability. Initial MC service UE configuration data may contain information for the PDU session to be used for each MC service (including among others the S-NSSAI).

MC services are service agnostic with respect to 5GS, i.e., the available service options are identical in both public networks (i.e. PLMN) and Non-Public Networks (NPNs). A Non-Public Network (NPN) can be deployed in organization defined premises and the 5G network services are provided to a defined set of users or organizations in accordance with TS 23.501.

An MC system shall be able to utilize connectivity from public 5GS networks and non-public 5GS networks in accordance with TS 23.501.

For the migration of an MC service user the general assumptions in clause 5.2.9.1 of TS 23.280 are applied.

Migrated MC service users should utilize the home PLMN of the partner MC system to access MC services in the partner MC system, however, utilizing the home PLMN of the primary MC system is not precluded. The MC service user profile enabled for migration shall be provisioned with configuration data that specifies which PLMNs supporting 5GS are to be selected when migrating to another MC system. If the home PLMN of a partner MC system is different from the home PLMN of the primary MC system (i.e. migrating MC service users roam into the home PLMN of the partner MC system), then:

• 5GS-level roaming is required between the home PLMN of the primary MC system and home PLMN of the partner MC system;
• the home PLMN of the partner MC system needs to enable local break-out for the DNNs in accordance to subclause 4.2.2 that identify the DNs of the partner MC system; and
• the 5GS user profile of the home PLMN of the primary MC system used by the MC service users who are allowed to migrate to the partner MC system needs to be provisioned with, and local break-out enabled for, the DNNs proposed in subclause 4.2.2 that identify the DNs of the partner MC system.

If the home PLMN of the partner MC system and the home PLMN of the primary MC system are the same (i.e. migrating MC service users continue to use the home PLMN of their primary MC system), then:

• the 5GS user profile of the home PLMN of the primary MC system utilized by the MC service users who are allowed to migrate to the partner MC system needs to be provisioned with the DNNs specified in subclause 4.2.2 that identify the DNs of the partner MC system.

When the NPN is a PNI-NPN as described in TS 23.501, the requirements in clause 4.6.2 are applicable. When the NPN is a SNPN as described in TS 23.501, the requirements may be different in the following options. Option 1:

• the 5GS user profile of the SNPN of the primary MC system utilized by the MC service users who are allowed to migrate to the partner MC system needs to be provisioned with the DNNs specified in subclause 4.2.2 that identify the DNs of the partner MC system.

Option 2:

• the migrated MC service users shall utilize the SNPN of the partner MC system to access MC service in the partner MC system.
• the 5GS user profile of the SNPN of the partner MC system used by the MC service users who are allowed to migrate to the partner MC system needs to be provisioned with the DNNs proposed in subclause 4.2.2 that identify the DNs of the partner MC system.
• the MC service UE shall have credentials to access the SNPN of the partner MC system. UE may access using credentials owned by a Credentials Holder separate from the SNPN of the partner MC system.

Option 3:

• the migrated MC service users should utilize the PLMN of the partner MC system to access MC service in the partner MC system.
• 5GS-level SNPN and PLMN interworking is required between the SNPN of the primary MC system and PLMN of the partner MC system if the migrated MC service users utilize the SNPN of the primary MC system to access MC service in the partner MC system.
• the 5GS user profile of the PLMN of the partner MC system used by the MC service users who are allowed to migrate to the partner MC system needs to be provisioned with the DNNs proposed in subclause 4.2.2 that identify the DNs of the partner MC system.

Option 4:

• the migrated MC service users should utilize the SNPN of the partner MC system to access MC service in the partner MC system.
• 5GS-level SNPN and PLMN interworking is required between the PLMN of the primary MC system and SNPN of the partner MC system if the migrated MC service users utilize the PLMN of the primary MC system to access MC service in the partner MC system.
• the MC service UE shall have credentials to access the SNPN of the partner MC system. UE may access using credentials owned by a Credentials Holder separate from the SNPN of the partner MC system.
• the 5GS user profile of the SNPN of the partner MC system used by the MC service users who are allowed to migrate to the partner MC system needs to be provisioned with the DNNs proposed in subclause 4.2.2 that identify the DNs of the partner MC system.