Content for  TR 22.851  Word version:  19.1.0

Despite the aircraft and rail have been developed to serve more and more regions, road transport remains the most important way to deliver goods. As the logistics industry is booming, the total length of long-distance road transport has increased every year in the last ten years. How to provide communication service during long-distance transport is valuable to be discussed serving the transportation and logistics customers. Network sharing offers a way for the network operator to share the heavy deployment of mobile networks, as well as improve the service availability and user experience along the transport routes. Compared with MOCN configuration, network sharing with the indirect connection between Shared NG-RAN and the core network of participating operators allows flexible access options for the sharing parties to consider. For example, one network operator needs to provide communication service along a dedicated transport route across dense urban, rural, and desert, but can't find one hosting operator with full coverage of the whole route. It's possible to cooperate with a terrestrial network operator and a 3GPP satellite network operator separately to ensure the full coverage. Also, with the agreement, it's possible to leverage the temporary coverage enhancement plan of hosting operators for certain regions, such as deploying onboard base stations in dense urban, to provide better user experience to their own users.

It is assumed that network operators OP1, OP2, and OP3 have deployed 5G networks respectively in a country. Their radio access network can provide coverage to different regions of the country, and together cover the entire country with overlapping in certain regions. OP1 and OP3 are agreed with OP2 to share radio access network in the planned geographic area via the indirect connection between their shared radio access network and OP2's core network.

• OP1 is a Hosting NG-RAN Operator, who has deployed different types of 5G access nodes (e.g., Macro, Micro, onboarding, and IAB). It only shares Macro base stations (e.g., 5G BS#A, BS#B, BS#C) with participating operator OP2 but allows to access to dedicated type of access nodes (e.g., onboarding) temporarily regarding the agreement and the policy.
• OP3 is another Hosting RAN Operator, sharing 3GPP Satellite access nodes with OP2.
• OP2 has non-shared 5G access network deployed in some regions of the country, as 4G & 5G BS.
• UE on the vehicle supports all 5G RATs and has the subscription with OP2's network.

1. UE on the vehicle connects to OP2's network via OP1 shared access nodes and is authorized to initiate a communication service (e.g., data transfer, IMS voice call) during the movement.
2. In geographic Area #A, UE connects to OP2's network only through the access nodes like 5G BS #A based on the agreement and the policies of OP1 and OP2.
3. A regional earthquake happens and results in unstable performance of 5G BS #B in Area #B. OP1's UAV base stations are shared to OP2 as a supplementary or an alternative access node based on OP1 and OP2 agreement.
4. When UE reaches Location Loc #A, where it can detect the radio signal of both 5G BS #B and UAV base station, UE will access a proper OP1 access node (e.g., 5G UAV BS ) to continue the service regarding the subscription, and the policy and agreement of OP1 and OP2.
5. When UE reaches Location Loc #B, where it can detect the radio signal of OP1 5G BS#C and OP3 Satellite access node, UE will access a proper Hosting RAN operator's access node (e.g., OP3 Satellite) to continue the service regarding the subscription and the policy and agreement of OP1, OP3 and OP2.
6. When UE reaches Location Loc #C, where it can detect the radio signal of OP3 Satellite access node and OP2 4G & 5G BS, UE will select OP2 5G BS to continue the service regarding the policies of OP3 and OP2.

UE can get services with the displayed serving network as OP2's network when move in OP1's Shared NG-RAN, across OP1's and OP3's shared RANs, and across OP3's shared RAN and OP2's non-shared RAN. OP2 ensures service continuity with proper mobility and access control to the shared access nodes of the same or different Host RAN Operators.

The normative stage1 requirements of network sharing has been introduced to TS 22.101 and TS 22.261 in previous releases. TS 22.101 specifies the service principle about Network Sharing that It shall be possible to support different mobility management rules, service capabilities and access rights as a function of the home PLMN of the subscribers. [ clause 4.9 ] The 3GPP System shall support a Shared RAN (E-UTRAN or NG-RAN) to cover a specific coverage area (e.g. from a complete network to a single cell, both outdoor and indoor). [ clause 28.2.1 ] The network sharing has been extended to different types of access networks, as stated TS 22.261. TS 22.261 has also illustrated general requirements about access, the mobility management and service continuity between different access networks as below. In MOCN configuration, that multiple shared access networks have direct connections to the Participating Operator's core network, the access control and mobility management are performed by Participating Operator's core network directly. However, in Indirect Network Sharing, besides Participating Operator's core network, Host RAN Operator's core network may be involved in the access control and mobility management. Also, UE may connect to Participating Operator's core network via the shared access nodes of different Host RAN Operators. TS 22.261 has defined requirements about multi-network connectivity and service delivery across operators as below.

[PR 5.7.6-001] [PR 5.7.6-002] [PR 5.7.6-003]