21.9163GPPRelease 16Release descriptionTS
Business Role Models for Network Slicing
Covell, Betsy, Nokia
Summary based on the input provided by Nokia in SP-200294.
This WI adds requirements to enable a 3GPP system to adequately support the variety of business role models for network slicing that are possible in a 5G system. The requirements address service exposure giving additional control to 3rd parties, impact of SLAs on network slice management, and non-public network access to MNO spectrum. Also addressed are security relationships between
- a UE and a private slice,
- a private slice and a network, and
- a private slice and other slices of the same network.
The requirements are captured in TS 22.261 .
The requirements from the BRMNS WI provide the means to support new business role models in vertical markets introduced for supporting vertical markets. These role models extend the possible interactions between Mobile Network Operators (MNOs) and 3rd parties who use the network and/or own/manage part of the network infrastructure. In particular, the introduction of network slicing allows new opportunities for 3rd parties to exercise additional control over the portions of the network, i.e., the network slice, supporting their network needs. Four key business relationship models were considered.
– Model 3a: MNO provides the virtual/physical infrastructure and V/NFs; a 3rd party uses the functionality provided by the MNO,
– Model 3b: MNO provides the virtual/physical infrastructure and V/NFs; a 3rd party manages some V/NFs via APIs exposed by the MNO,
– Model 3c: MNO provides virtual/physical infrastructure; a 3rd party provides some of the V/NFs,
– Model 3d: a 3rd party provides and manages some of the virtual/physical infrastructure and V/NFs.
Models 3a and 3b are supported by the Rel-15 network slicing requirements, with some enhancements in the Rel-16 APIs and management functions to extend 3rd party access and control of capabilities provided by the MNO, and to do so in a secure manner. In these two models, the 3rd party has greater control over the network capabilities that support its service. However, this control is limited to what is allowed by the MNO through the provided APIs. The Rel-16 enhancements allow the 3rd party to monitor the activities of their UEs when using the network slice and to monitor resource usage within the network slice. These capabilities are added to support SLAs between the MNO and the 3rd party.
As an example of the additional monitoring functionality, a network slice supporting a local smart grid needs additional APIs to monitor activities of many sensors throughout the grid and receive network status information that can be used to detect and resolve any communications problems that arise within the grid. Figure 2-1 from TR 22.830  illustrates the smart grid role models.
Figure 2-1: role model scenario between MNO and power grid company
Models 3c and 3d resulted in the addition of new functionality to support three new network management models.
- MNO manages all virtual/physical infrastructure and all V/NFs including 3rd party’s ones,
- 3rd party manages its own virtual/physical infrastructure and/or its own V/NFs; MNO manages the others.
- 3rd party manages virtual/physical infrastructure and/or V/NFs including its own virtual/physical infrastructure and/or V/NFs and some MNO’s virtual/physical infrastructure and/or V/NFs; MNO manages the others.
From the 3rd party perspective, the management role models 2 and 3 support the 3rd party management function and provide extended management for the MNO to coordinate with the 3rd party management. The 3rd party may use suitable APIs provided by the MNO to directly manage the V/NFs as well as the infrastructure resources so that it can properly handle when their business requirements are changed.
For models 3c and 3d, additional consideration is needed on the mechanisms to provide the isolation and interfaces that give the 3rd party the appropriate level of control while securing the PLMN. Specifically, where the 3rd party provides V/NFs or provides and manages some of the virtual/physical infrastructure and V/NFs, SLAs may be used to address some trust issues, such as what each party will provide and manage. However, the principles of trust and verification also come into play. The 3rd party must be able to verify, though the management interface, that all terms of the SLA are being met by the MNO. Similarly, the MNO must be able to verify that the 3rd party is managing resources appropriately so that there is no adverse impact to the rest of the network. Appropriate management interfaces are needed to support both the network operator and 3rd party.
Models 3c and 3d allow for additional interactions between non-public networks, private slices, and PLMNs as shown in the following figures from .
Figure 2-2: Example of enterprise communications using a combination of 5G PLMNs, a private slice, and a non-public network
Figure 2-3: Example of enterprise communications using a geographically constrained private slice
Figure 2-4: Example of enterprise communications using a private slice throughout the PLMN
Support for enterprise communications may be provided by a variety of network configurations, including multiple PLMNs, private slices, and non-public networks. New requirements allow for managing the enterprise communications in a coordinated manner across these various implementation options. New requirements also provide for isolation of private network resources which may be constrained for access within a geographic area such as a factory site or restricted for use only by UEs belonging to the enterprise. As a counterpart, additional requirements provide for restricting some enterprise UEs from accessing a PLMN, this may be useful for example to keep factory equipment connected to the private slice or non-public network when a PLMN covers the same area.
List of related CRs: select "TSG Status = Approved" in:
 TS 22.261 Service requirements for the 5G system
 TR 22.830 Feasibility Study on Business Role Models for Network Slicing