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Some acronyms from telecommunication world (but not only)

3GPP has its own list of terms - [21.905]


3GPP - 3rd Generation Partnership Project


AAA - Authentication Authorization Accounting
AAL - ATM Adaptation Layer
AMF - Access and Mobility Management Function
AMR - Adaptive Multi Rate
ARQ - Automatic Repeat Request
AS - Application Server


BCCH - Broadcast Control Channel
BICC - Bearer Independent Call Control
BGCF - Breakout Gateway Control Function
BLER - Block Error Rate
BSC - Base Station Controler
BSS - Base Station Subsystem
BTS - Base Transceiver Station
BWP - Bandwidth Part


CC - Call Control
CDMA - Code Division Multiple Access
CSCF - Call Session Control Function
CSFB - Circuit Switch Fallback
CM - Connection Management
CS - Circuit Switched
CQI - Channel Quality Indicator
CSI - Channel State Information
CPRI - Common Public Radio Interface
CU-CP - Control Unit - Control Plane
CU-UP - Control Unit - User Plane


DAPS - Dual Active Protocol Stack
DCH - Dedicated Channel
DCI - Downlink Control Information
DMRS - Demodulation Reference Signal
DRX - Discontinuous Reception
DTX - Discontinuous Transmission
DDDS - Downlink Data Delivery Status
DU - Distributed Unit


E-DCH - Enhanced Dedicated Channel
EDGE - Enhanced Data rates for GSM Evolution
EN-DC - E-UTRAN NR Dual Connectivity
EPC - Evolved Packet Core
EPS - Evolved Packet System
EUL - Enhanced Uplink
ETWS - Earthquake Tsunami Warning System


FDD - Frequency Division Duplex
FDMA - Frequency Divsion Multiple Access


GERAN - GSM/EDGE Radio Access Network
GGSN - Gateway GPRS Supporting Node
GMSC - Gateway Mobile Switching Center
GPRS - General Packet Radio Service
GSM - Global System for Mobile Telecommunication
GTP - GPRS Tunneling Protocol
GUAMI - Globally Unique AMF ID
GUTI - Global Unique Temporary Identifier


HARQ - Hybrid Automatic rePeat Request
HLR - Home Location Register
HSCSD - High Speed Circuit Switched Data
HSPA - High Speed Packet Access
HSS - Home Subscriber System


IAM - Initial Address Message
I-CSCF - Interrogating Call Session Control Function
ICT - Information and communications technology
IMEI - International Mobile Equipment Identity
IMS - IP Multimedia Subsystem
IMSI - International Mobile Subscriber Identity
IP - Internet Protocol
ISDN - Integrated Services Digital Network
ISR - Idle mode Signalling Reduction
ISUP - ISDN User Part
ITU - International Telecommunication Union


LA - Location Area
LAA - License Assisted Access
LAU - Location Area Update
LTE - Long Term Evolution


MAC - Medium Access Control
MCC - Mobile Country Code
MSC - Mobile Switching Center
MIMO - Multiple Input Multiple Output
MISO - Multiple Input Single Output
MGCF - Media Gateway Control Function
MGW - Media GateWay
MO - Mobile Originated
MME - Mobility Management Entity
MMTel - MultiMedia Telephony
MRFC - Media Resource Function Controller
MRFP - Media Resource Function Processor
MSC-S - Mobile Switching Center – Server
MT - Mobile Terminated
MCG - Master Cell Group
MBB - Mobile BroadBand
MIB - Master Information Block
MNC - Mobile Network Code


NMO - Network Mode of Operation / Network Operation Mode
NSA - Non Standalone


OFDM - Orthogonal Frequency Division Multiplexig
OFDMA - Orthogonal Frequency Division Multiple Access


PCRF - Policy Control Rule Function
PEI - Permanent Equipment Identifier
PUCCH - Physical Uplink Control Channel
PDCP - Packet Data Convergence Protocol
PWS - Public Warning System


QoE - Quality of Experience
QoS - Quality of Service
QAM - Quadrature Amplitude Modulation
QPSK - Quadrature Phase Shift Keying


RAN - Radio Access Network
RNC - Radio Network Controler
RA - Routing Area
RAU - Routing Area Update
RAT - Radio Access Technology
RNS - Radio Network Subsystem
RRC - Radio Resource Control
RTT - Round Trip Time
RLC - Radio Link Control
RNA - RAN Notification Area
RNTI - Radio Network Temporary Identifier


S-CSCF - Serving Call Session Control Function
SC-FDMA - Single Carrier Frequency Division Multiple Access
SAE - System Architecture Evolution
SBC - Session Border Controller
SLF - Subscription Locator Function
SIP - Session Initiation Protocol
SCTP - Stream Control Transmission Protocol
SGSN - Serving GPRS Supporting Node
SGW - Serving GateWay
SMS - Short Message Service
SMF - Session Management Function
SRVCC - Single Radio Voice Call Continuity
SS7 - Signalling System No 7
SISO - Single Input Single Output
SIMO - Single Input Multiple Output
SCG - Secondary Cell Group
S-NSSAI- Single Network Slice Selection Assistance Information
SUPI- Subscription Permanent Identifier
SUCI- Subscription Concealed Identifier


TA - Tracking Area
TAC - Tracking Area Code
TAI - Tracking Area Identity
TAU - Tracking Area Update
TDD - Time Division Duplex
TDMA - Time Division Mutiple Access
TDM - Time Division Multiplexing


UCI - Uplink Control Information
UTRAN - UMTS Terrestial Radio Access Network
UMTS - Universal Mobile Telecommunications System
UE - User Equipment
UPF - User Plane Function
UDM - Unified Data Management
UDP - User Datagram Protocol


V2V - Vehicle to Vehicle
V2X - Vehicle to Eveything
VLR - Visitor Location Register
VoIP - Voice over IP
VoLTE - Voice over LTE
VoNR - Voice over NR


WCDMA - Wideband Code Division Multiple Access
WDM - Wavelength Division Multiplexing

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