>EP_FIC <<IOC>>EP_E1 <<IOC>>EP_F1U en-gNB IOC>>EP_X2C, IOC EP_X2C, IOC>>P_X2C IOC>>EP_F1C, <<IOC>>P_F1C <<IOC>>EP_E1 in Section 4.5), Non-Real-Time RIC, and Near-Real-Time RIC. 10 For OAM aspects of the low-level split architecture, please refer to Section 4.5. 6.5.8 Management of Network Slicing 6.5.8.1 Basic Concepts of Slicing Management One of the new 5G features is slicing, which is described in Chapter 3. Here we discuss the OAM impacts of this feature. According to 3GPP TS 28.530, from a management point of view, an NSI is a subnetwork that includes all needed NF instances (including 5GC and NG-RAN), to provide a certain set of communication services to serve a certain business purpose. The management system controls the topology of the subnetwork together with the network resources allocated to the NSIs and associated QoS requirements. The NSSIs are building blocks for NSIs. The NSSI represents a group of NF instances (and their resources). NSIs and NSSIs can be composed of PNFs or VNFs or both. An important part of slicing management is management of virtualized and non-virtualized resources used by NSIs and NSSIs. In general, NSI is an E2E construct and therefore contains not only NFs from NG-RAN and 5GC, but also elements of transport network, (S)Gi-LAN¹ facilities, etc. 3GPP, within its scope, defined the management aspects of the parts of NSI or NSSI that belong to the 5GC and NG-RAN. There is also some provisioning for the management of the non-3GPP part, containing the transport NEs including backhaul, midhaul, and fronthaul parts, links, routers, firewalls, etc. In a typical scenario, the 3GPP management system provisions the network slicing-related aspects to non-3GPP parts via their respective (non-3GPP) manage- ment systems. NSSI may include NFs directly and via another constituent NSSI(s). Furthermore, an NF may be shared by two or more NSSIs. For example, a network operator may have most of 10 O-RAN RIC architectures are still work in progress and therefore are outside of scope of the book. 1