3 Definitions, symbols and abbreviations

36.4253GPPEvolved Universal Terrestrial Radio Access Network (E-UTRAN)Release 17TSX2 interface user plane protocol

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].

Master eNB: as defined in TS 36.300 [2].

Secondary eNB: as defined in TS 36.300 [2].

Split bearer: as defined in TS 36.300 [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].

DC Dual Connectivity

DL Downlink

E-RAB E-UTRAN Radio Access Bearer

MeNB Master eNB

SeNB Secondary eNB

UL Uplink

UP User Plane

X2 UP X2 User Plane