Blue Flower

U- 

User-

UBR 

Unspecified Bit Rate

UCD 

Uniform Call Distribution

UCP 

Universal Computer Protocol

UDD 

Unconstrained Delay Data

UDI 

Unrestricted Digital Information

UDP 

User Datagram Protocol

UDSL 

Universal ADSL also called "ADSL Lite" or "Splitterless ADSL"

UE 

User Equipment 

UE_R 

User Equipment with ODMA relay operation enabled

UICC 

UMTS Integrated Circuit Card

UL 

UpLink

UMTS 

Universal Mobile Telecommunications System

UNI 

User-Network Interface

UPC 

Usage Parameter Control

UPS 

Uninterruptable Power Supply

UpTS 

Uplink Pilot Time Slot

URA 

UTRAN Registration Area

URI 

Uniform Resource Identifier

URL 

Uniform Resource Locator

USAT 

USIM Application Toolkit

USB 

Universal Serial Bus

USCH 

Uplink Shared Channel

USIM 

UMTS Subscriber Identity Module

USSD 

Unstructured Supplementary Service Data

UTOPIA 

Universal Test & Operations Interface for ATM

UTP 

Unshielded Twisted Pair

UTRA 

UMTS Terrestrial Radio Access

UTRAN 

UMTS Terrestrial Radio Access Network

UTX 

Unrated Transaction Record

UUS 1 

User to User Signalling

UWC 

Universal Wireless Communication