3GPP has completed 3GPP 5G architecture stage 2 level specifications. With this Release 15 milestone, 3GPP has provided the set of features and functionality needed for deploying a commercially operational 5G system. The delivered specifications are TS 23.501, TS 23.502 and TS 23.503.

The 5G stage 2 level specifications include the overall architecture model and principles, eMBB data services, subscriber authentication and service usage authorization, application support in general, but also specifically for applications closer to the radio as with edge computing. Its support for IMS includes also emergency and regulatory services specifics. 

The delivered stage 2 level specifications define the 3GPP 5G system from an overall, architectural perspective. The related work in the RAN, security, OAM and CT working groups continues with some specific stage 2 level aspects and with delivering stage 3 level specifications until June 2018. Studies concerning Phase 2 of 5G will begin in first quarter of 2018.

5G service based architecture model uniformly enables user services with different access systems, like fixed network access or WLAN, from the onset. Further, the system architecture provides interworking with and migration from 4G, network capability exposure and numerous other functionalities.

3GPP brings an important feature network slicing with this release. A network slice refers to the set of 3GPP defined features and functionalities that together form a complete PLMN for providing services to UEs. Network slicing allows for controlled composition of a PLMN from the specified network functions with their specifics and provided services that are required for a specific usage scenario.