3 Definitions and abbreviations

38.3233GPPNRPacket Data Convergence Protocol (PDCP) specificationRelease 17TS

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].

AM DRB: a data radio bearer which utilizes RLC AM.

AM MRB: an MRB associated with at least one AM RLC bearer for PTP transmission.

Broadcast MRB: a radio bearer configured for MBS broadcast delivery.

DAPS bearer: a bearer whose radio protocols are located in both the source gNB and the target gNB during DAPS handover to use both source gNB and target gNB resources.

MBS Radio Bearer: a radio bearer that is configured for MBS delivery.

Multicast MRB: a radio bearer configured for MBS multicast delivery.

Non-split bearer: a bearer whose radio protocols are located in either the MgNB or the SgNB to use MgNB or SgNB resource, respectively.

NR sidelink communication: AS functionality enabling at least V2X communication as defined in TS 23.287 [13] and ProSe communication (including ProSe Relay) as defined in TS 23.304 [18], between two or more nearby UEs, using NR technology but not traversing any network node.

PDCP data volume: the amount of data available for transmission in a PDCP entity.

Sidelink discovery: AS functionality enabling 5G ProSe UE-to-Network Relay Discovery or 5G ProSe Direct Discovery as defined in TS 23.304 [18], using NR technology but not traversing any network node.

Split bearer: in dual connectivity, a bearer whose radio protocols are located in both the MgNB and the SgNB to use both MgNB and SgNB resources.

Split secondary RLC entity: in dual connectivity, the RLC entity other than the primary RLC entity which is responsible for split bearer operation. If the PDCP entity is associated with two RLC entities, the split secondary RLC entity is the RLC entity other than the primary RLC entity. If the PDCP entity is associated with more than two RLC entities, the split secondary RLC entity is configured by upper layers.

UM DRB: a data radio bearer which utilizes RLC UM.

UM MRB: an MRB associated with only RLC UM.

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].

AM Acknowledged Mode

ARP Address Resolution Protocol

CID Context Identifier

DAPS Dual Active Protocol Stack

DRB Data Radio Bearer carrying user plane data

EHC Ethernet Header Compression

FIFO First In First Out

gNB NR Node B

HFN Hyper Frame Number

IETF Internet Engineering Task Force

IP Internet Protocol

MAC Medium Access Control

MAC-I Message Authentication Code for Integrity

MBS Multicast/Broadcast Services

MRB MBS Radio Bearer

MTCH MBS Traffic Channel

PDCP Packet Data Convergence Protocol

PDU Protocol Data Unit

RB Radio Bearer

RFC Request For Comments

RLC Radio Link Control

ROHC RObust Header Compression

RRC Radio Resource Control

RTP Real Time Protocol

SAP Service Access Point

SCCH Sidelink Control Channel

SDU Service Data Unit

SLRB Sidelink Radio Bearer carrying NR sidelink communication or sidelink discovery

SN Sequence Number

SRAP Sidelink Relay Adaptation Protocol

SRB Signalling Radio Bearer carrying control plane data

STCH Sidelink Traffic Channel

TCP Transmission Control Protocol

UDC Uplink Data Compression

UDP User Datagram Protocol

UE User Equipment

UM Unacknowledged Mode

U2N UE-to-Network

X-MAC Computed MAC-I