For the purposes of the present document, the terms and definitions given in TR 21.905
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
Common Tunnel Endpoint Identifier (C-TEID):
Unambiguously identifies a tunnel endpoint in the receiving GTP-U protocol entity for a given UDP/IP endpoint. The sending end side of a GTP tunnel locally assigns the C-TEID value used in the TEID field and signals it to the destination Tunnel Endpoint using a control plane message.
GTP-U (user plane) messages are either user plane messages or signalling messages. User plane messages are used to carry user data packets between GTP-U entities. Signalling messages are sent between network nodes for path management and tunnel management.GTP-U peer: node implementing at least one side of any of the GTP user plane based protocols. RNC, SGSN, GGSN, eNodeB, SGW, ePDG, gNB, N3IWF, UPF, PGW or TWAN or MME.
A GTP-U tunnel is identified in each node with a TEID, an IP address and a UDP port number. A GTP-U tunnel is necessary to enable forwarding packets between GTP-U entities.
GTP-U Tunnel Endpoint:
A GTP-U tunnel endpoint identifies a user plane context (e.g EPS bearer, PDU session or a RAB) for which a received GTP-U packet is intended. A given GTP-U tunnel endpoint may receive GTP-U packets from more than one source GTP-U peer (See clause 4.3.0
).UDP/IP Path: Connection-less unidirectional or bidirectional path defined by two end-points. An IP address and a UDP port number define an end-point. A UDP/IP path carries GTP messages between network nodes related to one or more GTP tunnels.
GTP Protocol Data Unit (PDU) is a GTP-U message, which may be either a G-PDU or a signalling message.
User data packet (T-PDU) plus GTP-U header, sent between GTP network nodes.
A GTP-U message (GTP-PDU that is not a G-PDU) sent between GTP network nodes. These may be Path Management messages or Tunnel Management messages.
A user data packet, for example an IP datagram, sent between a UE and a network entity in an external packet data network. A T-PDU is the payload that is tunnelled in the GTP-U tunnel.
Tunnel Endpoint Identifier (TEID):
Unambiguously identifies a tunnel endpoint in the receiving GTP-U protocol entity for a given UDP/IP endpoint. The receiving end side of a GTP tunnel locally assigns the TEID value the transmitting side has to use. The TEID values are exchanged between tunnel endpoints using control plane message.
Trusted WLAN Access Network:
For the purposes of the present document, the abbreviations given in TR 21.905
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
Common Tunnel Endpoint IDentifier
E-UTRA-NR Dual Connectivity
Evolved Packet Data Gateway
GPRS Support Node
Gateway GPRS Support Node
GTP encapsulated user Plane Data Unit
GPRS Tunnelling Protocol
Internet Group Management Protocol
Internet Protocol version 4
Internet Protocol version 6
Mobility Management Entity
Packet Data Unit
Quality of Service
Radio Access Network Application Part
Radio Network Controller
Serving GPRS Support Node
Tunnel Endpoint IDentifier
Trusted WLAN Access Network
User Datagram Protocol
UMTS Terrestrial Radio Access Network