5G slicing terms and abbreviations
Plain-English definitions for the architecture, identifiers and service concepts used throughout the site.
5QI
5G QoS Identifier. References QoS characteristics for a QoS flow.
AF
Application Function. Provides application information that may influence authorised network policy or routing.
AMF
Access and Mobility Management Function. Handles registration, reachability, mobility and access-related signalling.
AUSF
Authentication Server Function. Supports primary authentication in the 5G System.
BSF
Binding Support Function. Helps identify the policy function associated with a session.
CHF
Charging Function. Supports converged charging for network use.
DNN
Data Network Name. Identifies the data network associated with a PDU session.
MEC
Multi-access edge computing. Places applications or processing close to users and access networks.
NEF
Network Exposure Function. Securely exposes approved network capabilities and events.
NRF
Network Repository Function. Supports network-function registration and discovery.
NSSAI
Network Slice Selection Assistance Information. A set of one or more S-NSSAIs.
NSSF
Network Slice Selection Function. Supports suitable slice and AMF selection.
NWDAF
Network Data Analytics Function. Produces analytics for authorised consumers.
PCF
Policy Control Function. Provides policy decisions affecting access, sessions, QoS and charging.
PDU session
The logical connection between a device and a data network in the 5G System.
QFI
QoS Flow Identifier. Identifies a QoS flow within a PDU session.
QoS flow
The finest granularity of QoS forwarding treatment in the 5G System.
RAN
Radio Access Network. The radio domain connecting devices to the Core.
S-NSSAI
Single Network Slice Selection Assistance Information. An SST plus optional SD.
SBA
Service-Based Architecture. The 5G Core framework in which network functions provide services to authorised consumers.
SCP
Service Communication Proxy. Supports indirect service communication and routing between network functions.
SD
Slice Differentiator. An optional value distinguishing slices that use the same SST.
SMF
Session Management Function. Controls PDU sessions and user-plane selection.
SST
Slice/Service Type. The broad category of a slice.
UDM
Unified Data Management. Provides subscriber-related data-management services.
UDR
Unified Data Repository. Stores structured data used by authorised network functions.
UDSF
Unstructured Data Storage Function. Stores unstructured state information for network functions.
UE
User Equipment. A phone, router, sensor, gateway or other device using the mobile network.
UPF
User Plane Function. Forwards subscriber packets towards data networks.
gNodeB
The 5G New Radio base-station function connecting devices to the 5G Core.