Universal Mobile Telecommunications System (UMTS); LTE; General Packet Radio System (GPRS) Tunnelling Protocol User Plane (GTPv1-U) (V12.0.0; 3GPP TS 29.281 version 12.0.0 Release 12)
The present document defines the user plane of GTP used on: the Gn and Gp interfaces of the General Packet Radio Service (GPRS); the Iu@ Gn and Gp interfaces of the UMTS system; the S1-U@ S2a@ S2b@ X2@ S4@ S5@ S8@ S12@ M1 and Sn interfaces of the Evolved Packet System (EPS); This definition ensures full backwards compatibility with RNC@ SGSN and GGSN implementations according to release 7 of 3GPP TS 29.060 [6]. NOTE: Releases previous to Release-8 have used 3GPP TS 29.060 [6] as normative definition of the user plane of GTP. This shall be considered when essential corrections are included in the present document or in pre-release-8 version of 3GPP TS 29.060 [6]. Fallback from GTPv1-U to GTPv0-U shall not be supported. Therefore@ 3GPP Rel-8 and onwards GTPv1-U entity should not listen to the well-known GTPv0 port 3386. If GTPv1 entity listens to the GTPv0 port@ the entity shall silently discard any received GTPv0-U message.