Content for TR 21.905 Word version: 17.0.0
4.T T Word‑p. 55
T-SGW
Transport Signalling Gateway
T
Timer
Transparent
Type only
TA
Terminal Adaptation
Timing Advance
Tracking Area
TAC
Type Approval Code
TAF
Terminal Adaptation Function
TAR
Toolkit Application Reference
TB
Transport Block
TBD
To Be Defined
TBF
Temporary Block Flow
TBR
Technical Basis for Regulation
TC
Transaction Capabilities
TransCoder
Transmission Convergence
TCH
Traffic Channel
TCH/F
A full rate TCH
TCH/F2,4
A full rate data TCH (≤2,4kbit/s)
TCH/F4,8
A full rate date TCH (4,8kbit/s)
TCH/F9,6
A full rate data TCH (9,6kbit/s)
TCH/FS
A full rate Speech TCH
TCH/H
A half rate TCH
TCH/H2,4
A half rate data TCH (≤2,4kbit/s)
TCH/H4,8
A half rate data TCH (4,8kbit/s)
TCH/HS
A half rate Speech TCH
TC-TR
Technical Committee Technical Report
TCI
Transceiver Control Interface
TCP
Transmission Control Protocol
TD-CDMA
Time Division-Code Division Multiple Access
TDD
Time Division Duplex(ing)
TDMA
Time Division Multiple Access
TDoc
Temporary Document
TE
Terminal Equipment
TE9
Terminal Equipment 9 (ETSI sub-technical committee)
Tei
Terminal endpoint identifier
TEID
Tunnel End Point Identifier
TF
Transport Format
TFA
TransFer Allowed
TFC
Transport Format Combination
TFCI
Transport Format Combination Indicator
TFCS
Transport Format Combination Set
TFI
Transport Format Indicator
Temporary Flow Identity
TFIN
Transport Format INdicator
TFP
TransFer Prohibited
TFS
Transport Format Set
TFT
Traffic Flow Template
TI
Transaction Identifier
TLLI
Temporary Logical Link Identity
TLM
TeLeMetry word
TLS
Transport Layer Security
TLV
Tag Length Value
TM
Telecom Management
Transparent Mode
TMA
Tower Mounted Amplifier
TMAAP
Tower Mounted Amplifier application part
TMF
Telecom Management Forum
TMN
Telecom Management Network
TMSI
Temporary Mobile Subscriber Identity
TN
Termination Node
Timeslot Number
TNL
Transport Network Layer
TO
Telecom Operations Map
TOA
Time of Arrival
TON
Type Of Number
TP
Third Party
TPC
Transmit Power Control
TPDU
Transfer Protocol Data Unit
TR
Technical Report
TRAU
Transcoder and Rate Adapter Unit
TrCH
Transport Channel
TRX
Transceiver
TS
Technical Specification
Teleservice
Time Slot
TSC
Training Sequence Code
TSDI
Transceiver Speech & Data Interface
TSG
Technical Specification Group
TSN
Time-Sensitive Networking
TSTD
Time Switched Transmit Diversity
TTCN
TTCN-2 or TTCN-3
TTCN-2
Tree and Tabular Combined Notation version 2
TTCN-3
Testing and Test Control Notation version 3
TTI
Transmission Timing Interval
TUP
Telephone User Part (SS7)
TV
Type and Value
TX
Transmit
TXPWR
Transmit PoWeR; Tx power level in the MS_TXPWR_REQUEST and MS_TXPWR_CONF parameters
4.U U Word‑p. 57
U-plane
User plane
U-RNTI
UTRAN Radio Network Temporary Identity
UARFCN
UTRA Absolute Radio Frequency Channel Number
UARFN
UTRA Absolute Radio Frequency Number
UART
Universal Asynchronous Receiver and Transmitter
UAV
Unmanned Aerial Vehicle
UCS2
Universal Character Set 2
UDD
Unconstrained Delay Data
UDI
Unrestricted Digital Information
UDP
User Datagram Protocol
UDUB
User Determined User Busy
UDCH
User-plane Dedicated CHannel
UE
User Equipment
UER
User Equipment with ODMA relay operation enabled
UEM
operating band Unwanted Emissions Mask
UHD
Ultra-High Definition
UI
User Interface
Unnumbered Information (Frame)
UIA
3G Integrity Algorithm
UIC
Union Internationale des Chemins de Fer
UL
Uplink (Reverse Link)
UL-SCH
Uplink Shared channel
UM
Unacknowledged Mode
UML
Unified Modelling Language
UMS
User Mobility Server
UMSC
UMTS Mobile Services Switching Centre
UMTS
Universal Mobile Telecommunications System
UNI
User-Network Interface
UP
User Plane
UPCMI
Uniform PCM Interface (13-bit)
UPE
User Plane Entity
UPD
Up to date
UpPTS
Uplink Pilot Timeslot
UPT
Universal Personal Telecommunication
URA
User Registration Area
UTRAN Registration Area
URAN
UMTS Radio Access Network
URB
User Radio Bearer
URI
Uniform Resource Identifier
URL
Uniform Resource Locator
URLLC
Ultra-Reliable Low Latency Communication
USAT
USIM Application Toolkit
USB
Universal Serial Bus
USC
UE Service Capabilities
USCH
Uplink Shared Channel
USF
Uplink State Flag
USIM
Universal Subscriber Identity Module
USSD
Unstructured Supplementary Service Data
UT
Universal Time
UTRA
Universal Terrestrial Radio Access
UTRAN
Universal Terrestrial Radio Access Network
UUI
User-to-User Information
UUS
Uu Stratum
User-to-User Signalling
4.V V Word‑p. 58
V
Value only
V2X
Vehicle-to-Everything
VA
Voice Activity factor
VAD
Voice Activity Detection
VAP
Videotex Access Point
VASP
Value Added Service Provider
VBR
Variable Bit Rate
VBS
Voice Broadcast Service
VC
Virtual Circuit
VGCS
Voice Group Call Service
VHE
Virtual Home Environment
VLAN
Virtual LAN
VLR
Visitor Location Register
VMSC
Visited MSC
VoIP
Voice Over IP
VPLMN
Visited Public Land Mobile Network
VPN
Virtual Private Network
VR
Virtual Reality
VRB
Virtual Resource Block
VSC
Videotex Service Centre
V(SD)
Send state variable
VTX host
The components dedicated to Videotex service
4.W W
WA
Wide Area
WAAS
Wide Area Augmentation System
WAE
Wireless Application Environment
WAP
Wireless Application Protocol
WBEM
Web Based Enterprise Management
WCDMA
Wideband Code Division Multiple Access
WDP
Wireless Datagram Protocol
WG
Working Group
WGS-84
World Geodetic System 1984
WIM
Wireless Identity Module
WIN
Wireless Intelligent Network
WLAN
Wireless Local Area Network
WLAN UE
WLAN User Equipment
WPA
Wrong Password Attempts (counter)
WS
Work Station
WSP
Wireless Session Protocol
WTA
Wireless Telephony Applications
WTAI
Wireless Telephony Applications Interface
WTDD
Wideband Time Division Duplexing
WTLS
Wireless Transport Layer Security
WTP
Wireless Transaction Protocol
WTX
Waiting Time eXtenstion
WWT
Work Waiting Time
WWW
World Wide Web
4.X X Word‑p. 59
X2-C
X2-Control plane
X2-U
X2-User plane
XID
eXchange IDentifier
XMAC
exXpected Message Authentication Code (calculated by the USIM application in 3G AKA)
XML
eXtensible Markup Language
XRES
EXpected user RESponse
4.Y Y
<void>
4.Z Z
ZC
Zone Code
