The present document studies various use cases and scenarios using network slices, in order to identify potential service requirements for the 5G system, e.g.:

• when there is a restriction of network slice to e.g., certain frequency bands/sub bands, RATs, geographical areas, networks and applications,
• when a UE has a subscription to multiple network slices and these network slices are deployed for e.g., different frequency bands/sub bands, RATs, geographical area and applications,
• when there is a preference or prioritization for a network slice over other network slices e.g. when there are conflicting constraints on network slice availability.

The present document also includes a gap analysis of its derived potential requirements versus existing 3GPP requirements.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

• References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.

The concept of network slice was discussed from the beginning of the study for 5G system. Network slicing supports the flexible use of network resources so that multiple networks customized to the needs of each set of applications can be provided simultaneously over the network resources while ensuring resource isolation and meeting different SLAs. As more diverse industries start to use the capabilities provided by 5G system and various new services are implemented over the 5G system, the expected service requirements on the 5G system vary. To meet these diverse requirements on the network, the use of network slices will increase further as 5G system deployments are expanded. When configuring network slices within its network, each network operator may consider various factors, such as required QoS of the applications supported over the network slices, the amount of required network resources to support the applications, the expected geographical and time boundary where the network slice services need to be provided, the usable and deployed network resources at the location where the applications are used, the number of users, the type of devices (e.g., IIoT), etc. After considering these factors, a network operator may provide a network slice for different services to users. Similarly, 3rd parties may be authorized by the network operator to configure their own network slices based on these various criteria, within the bounds of an SLA with the network operator. However, the provisioning of network slices can be complicated, such as when a UE requests the simultaneous use of multiple network slices where the configurations for those network slices may not be compatible, when network slices are deployed over different network resources due to isolation requirements, when location based applications have specific requirements based on time of the day, or when the available networks support different sets of network slices.