Tunnel Endpoint Identifier

The TEID serves as a unique identifier for a tunnel endpoint within the GTP-U (GPRS Tunnelling Protocol – User) or GTP-C (GPRS Tunnelling Protocol – Control) protocol entity. When establishing a GTP tunnel, the receiving entity assigns a TEID locally, which is used by the transmitting side. TEID values are exchanged between tunnel endpoints via GTP-C messages (or RANAP in UTRAN) or GTPv2-C messages in LTE networks.