For the purposes of the present document, the terms and definitions given in TR 21.905 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905. 5G Core Network: AMF Region: AMF Set: en-gNB: gNB: gNB Central Unit (gNB-CU): gNB-CU-Control Plane (gNB-CU-CP): gNB-CU-User Plane (gNB-CU-UP): gNB Distributed Unit (gNB-DU): ng-eNB: NG-RAN:

For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905. 5GC 5GS AMF EN-DC EPS MR-DC NG-RAN NR PCF UDM UDR UDSF

According to NG-RAN architecture defined in TS 38.300, An NG-RAN node is either a gNB or an ng-eNB connected to 5GC. A gNB may consist of a gNB-CU and one or more gNB-DU(s), and a gNB-CU may consist of a gNB-CU-CP and one or more gNB-CU-UP. From functional split point of view, there have following gNB deployment scenarios which are specified in TS 38.401:

1. gNB which does not consist split function.
2. gNB which consists of gNB-CU and gNB-DU(s).
3. gNB which consists of gNB-CU-CP, gNB-CU-UP(s) and gNB-DU(s).

Abovementioned deployment scenarios apply to en-gNB also. Part of gNB (e.g. gNB-CU) can be deployed as virtualized network function.

Besides single connectivity operation, E-UTRAN, NR and NG-RAN support Multi-RAT Dual Connectivity (MR-DC) operation defined in TS 37.340, which can be further divided into following two categories based on connected core network types.

1. MR-DC with the EPC via EN-DC, the NR node in EN-DC is called en-gNB.
2. MR-DC with the 5GC via either NG-RAN E-UTRA-NR Dual Connectivity (NGEN-DC) or NR-E-UTRA Dual Connectivity (NE-DC).

There are different user plane connectivity options of the master node and secondary node involved in MR-DC (see detail in TS 37.340).

The 5G architecture is defined as service-based and the interaction between network functions is represented in the following two ways:

• Service-based representation
• Reference point representation

The network functions composed 5GC is specified in TS 23.501, network functions within the 5GC control plane shall only use service-based interfaces for their interactions.

5G system architecture allows UDM, PCF and NEF to store their data in the Unified Data Repository (UDR), and allows any NF to store and retrieve its unstructured data (e.g. UE context) into/from a UDSF.

When deploying AMF Region or AMF Set, AMF load balancing insides AMF Region/AMF Set is achieved by setting a weight factor for each AMF according to its relative capacity compared to other AMFs, see detail in clause 5.19.3 of TS 23.501.

Edge computing enables operator and 3rd party services to be hosted close to the UE's access point of attachment, so as to achieve an efficient service delivery through the reduced end-to-end latency and load on the transport network, see details in clause 5.13 of TS 23.501.

The general information used to describe network slice instance and network slice subnet instance are specified in TS 28.531.

A remote interference scenario may involve a number of victim and aggressor cells, where the gNBs execute Remote Interference Management (RIM) coordination on behalf of their respective cells. Aggressor and victim gNBs or cells can be grouped into semi-static sets, where each cell is asigned a set ID, and is configured with a RIM Reference Signal (RIM-RS) and the radio resources associated with the set ID. As defined in TS 38.300.

The following specific requirements apply to NG-RAN: REQ-NGRAN_NRM-CON-001: REQ-NGRAN_NRM-CON-002: REQ-NGRAN_NRM-CON-003: REQ-NGRAN_NRM-CON-004: REQ-NGRAN_NRM-CON-005: REQ-NGRAN_NRM-CON-006: REQ-NGRAN_NRM-CON-007: REQ-NGRAN_NRM-CON-008: REQ-NGRAN_NRM-CON-009:

The following specific requirements apply to MR-DC management, including management of NR in EN-DC and other MR-DC operations. REQ-MRDC_NRM-CON-001: REQ-MRDC_NRM-CON-002: REQ-MRDC_NRM-CON-003: REQ-MRDC_NRM-CON-004: REQ-MRDC_NRM-CON-005: REQ-MRDC_NRM-CON-006:

The following specific requirements apply to management of 5GC NFs: REQ-5GC_NRM-CON-001: REQ-5GC_NRM-CON-002: REQ-5GC_NRM-CON-003: REQ-5GC_NRM-CON-004: REQ-5GC_NRM-CON-005: REQ-5GC_NRM-CON-006: REQ-5GC_NRM-CON-007:

REQ-AMFSET_NRM-CON-001:

REQ-ECM_NRM-CON-001:

The following requirements apply to network slice and network slice subnet: REQ-NS_NRM-CON-001: REQ-NS_NRM-CON-002: REQ-NS_NRM-CON-003:

REQ-NGRAN_NRM-CON-001: