System architecture
Last updated
Last updated
References points representation.
shows the interaction that exists between the NF services in the network.
functions described by point-to-point reference points (e.g. N11).
between any two network functions (e.g. AMF and SMF).
Service-based representation where network functions (e.g. AMF) within the control plane enable other authorized network functions to access their services.
Network Functions are self-contained, independent, and reusable. Each Network Function service exposes and makes available its functionality (services) through a Service Based Interface (SBI), which employs a well-defined REST interface using HTTP/2.
Access and Mobility Management Function (AMF).
Termination of NAS signaling.
NAS ciphering & integrity protection.
Registration management.
Connection management.
Mobility management.
Access authentication and authorization.
Security context management.
Session Management Function (SMF).
Session management (establishment, modification, release).
UE IP address allocation & management.
UPF selection and configuration for QoS and traffic steering.
DHCP functions.
Lawful intercept functions.
Charging data collection and support of charging interfaces.
Policy Control Function (PCF).
Supports unified policy framework to govern network behavior.
Provides policy rules to Control Plane function(s) to enforce them.
Accesses subscription information relevant to policy decisions in a Unified Data Repository (UDR).
Authentication Server Function (AUSF).
Acts as an authentication server for 3GPP access and untrusted non-3GPP access.
Unified Data Management (UDM).
Generation of 3GPP Authentication and Key Agreement (AKA) credentials.
User Identification handling.
Access authorization based on subscription data.
Lawful Intercept functionality.
Subscription management.
Network Slice Selection Function (NSSF).
Selecting of the Network Slice instances serving the UE.
Selecting of the Network Slice instances serving the UE.
Determining the AMF set to be used to serve the UE.
Network Exposure function (NEF).
Exposure of capabilities and events.
Secure provision of information from external application to 3GPP network.
Translation of internal/external information.
NF Repository function (NRF).
Supports service discovery function.
Maintains the NF profile of available NF instances and their supported services.
User Plane Function (UPF).
Packet routing & forwarding.
Anchor point for Intra-/Inter-RAT mobility.
External PDU session point of interconnect to Data Network.
Packet inspection and User plane part of Policy rule enforcement.
Lawful intercept (UP collection).
Traffic usage reporting.
Uplink classifier (ULCL) to support routing traffic flows to a data network.
QoS handling for user plane, e.g. packet filtering, gating, UL/DL rate enforcement.
Transport level packet marking in the uplink and downlink.
Downlink packet buffering and downlink data notification triggering.
Application Function (AF).
Application influence on traffic routing.
Accessing Network Exposure Function.
Interacting with the Policy framework for policy control.
Data Network (DN).
Operator services.
Internet access.
3rd party services.
May be a Local Area Data Network (LADN):
a DN that is accessible by the UE only in specific locations, that provides connectivity to a specific Data Network Name (DNN), and whose availability is provided to the UE.
Unstructured Data Storage Function (UDSF).
Unified Data Repository (UDR).
