U


u-plane

UBR

UBT

UCT

UDP

UE

UECM

UI

UIC

UICC

ULI

UMTS

UNI

UNIVTRM

UNIX

UPF

URPF

URL

URR

User Manager

user plane

user VPLS

USM

USRPNL

USU

UTC

UTRAN

UWAN