Browse topics
38 topics across protocols, nodes, security, roaming, and more
38 topics
2G GSM
Global System for Mobile Communications — the digital cellular standard
3G UMTS
Universal Mobile Telecommunications System — the wideband CDMA mobile standard
4G EPC
The Evolved Packet Core — the all-IP mobile core defined in 3GPP Release 8
5G NSA
5G Non-Standalone — 5G NR radio anchored to the 4G Evolved Packet Core
5G SA
5G Standalone — the cloud-native Service-Based Architecture core for 5G networks
AMF
Access and Mobility Management Function — the 5G control plane anchor
AUSF
Authentication Server Function — the 5G authentication anchor
Diameter
The 4G/5G signalling protocol for authentication, policy, and mobility
DRA
Diameter Routing Agent — the Diameter signalling hub
GGSN
Gateway GPRS Support Node — the 2G/3G packet data gateway
GTP-C
GPRS Tunnelling Protocol — Control Plane for session and bearer management
GTP-U
GPRS Tunnelling Protocol — User Plane for subscriber data encapsulation
HLR
Home Location Register — the subscriber database of 2G/3G networks
HSS
Home Subscriber Server — the 4G master subscriber database
IMS Core
IP Multimedia Subsystem — the voice and multimedia session core
ISUP
ISDN User Part — the SS7 protocol for circuit-switched call control
MAP
Mobile Application Part — the SS7 signalling protocol for mobile networks
MME
Mobility Management Entity — the 4G EPC control plane anchor
MSC
Mobile Switching Centre — 2G/3G circuit-switched call controller
NEF
Network Exposure Function — the 5G API gateway to external applications
NRF
Network Repository Function — the 5G service registry and discovery hub
PGW
PDN Gateway — the 4G PDN anchor, IP allocation, and policy enforcement point
PCF
Policy Control Function — unified policy engine for 5G SA networks
PCRF
Policy and Charging Rules Function — the 4G EPC policy engine
PFCP
Packet Forwarding Control Protocol — the N4 control plane between SMF and UPF
RTP
Real-time Transport Protocol — the media bearer for VoLTE and IMS voice
SGW
Serving Gateway — the 4G user plane anchor for intra-LTE mobility
SCTP
Stream Control Transmission Protocol — transport bearer for SS7 and Diameter
SEPP
Security Edge Protection Proxy — 5G inter-PLMN security gateway
SGSN
Serving GPRS Support Node — 2G/3G packet data mobility manager
SIGTRAN
SS7 signalling over IP — IETF adaptation layers for telecom packet networks
SIP
Session Initiation Protocol — the signalling backbone of IMS voice and messaging
SMF
Session Management Function — PDU session control and UPF orchestration
SMSC
Short Message Service Centre — the store-and-forward hub for SMS delivery
SS7
Signalling System No. 7 — the global telephony signalling backbone
STP
Signal Transfer Point — the SS7 network routing node
UDM
Unified Data Management — 5G subscriber data repository
UPF
User Plane Function — traffic forwarding anchor in the 5G packet core