3 Definitions and abbreviations

36.4103GPPEvolved Universal Terrestrial Radio Access Network (E-UTRAN)Release 17S1 general aspects and principlesTS

3.1 Definitions

For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply.
A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].

Dual Connectivity: mode of operation of a UE in RRC_CONNECTED, configured with a Master Cell Group and a Secondary Cell Group as defined in TS 36.300 [11].

E-RAB: as defined in 3GPP TS 36.401 [2].

3.2 Abbreviations

For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply.
An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905 [1].

AS Access Stratum

CMAS Commercial Mobile Alert Service

DC Dual Connectivity

E-RAB E-UTRAN Radio Access Bearer

eNB E-UTRAN Node B

EPC Evolved Packet Core

EPS Evolved Packet System

ETWS Earthquake and Tsunami Warning System

GTP-U GPRS Tunnelling Protocol

IP Internet Protocol

LTE Long Term Evolution

MeNB Master eNB

MME Mobility Management Entity

O&M Operation and Maintenance

PWS Public Warning System

QoS Quality of Service

RAT Radio Access Technology

RIM RAN Information Management

RNL Radio Network Layer

S1-U S1 User plane interface

S1-MME S1 control plane interface

S-GW Serving Gateway

S1AP S1 Application Protocol

SAP Service Access Point

SCG Secondary Cell Group

SeNB Secondary eNB

SCTP Stream Control Transmission Protocol

TNL Transport Network Layer

3.3 Specification notations

For the purposes of the present document, the following notations apply:

Procedure When referring to a procedure in the specification the Procedure Name is written with the first letters in each word in upper case characters followed by the word "procedure", e.g. Radio Network Layer (RNL) procedures.

Message When referring to a message in the specification the MESSAGE NAME is written with all letters in upper case characters followed by the word "message", e.g. RADIO LINK SETUP REQUEST message.