Direct Tunnel
Direct Tunnel Feature Overview ▀
Cisco ASR 5x00 Packet Data Network Gateway Administration Guide ▄
247
1.
Direct Tunneling - 3G Network
LTE network
: When Gn/Gp interworking with pre-release 8 (3GPP) SGSNs is enabled, the GGSN service on
the P-GW supports direct tunnel functionality. The SGSN establishes a user plane (GTP-U) tunnel directly
between the RNC and the GGSN/P-GW, using an Update PDN Context Request toward the GGSN/P-GW.
2.
Direct Tunneling - LTE Network, GTP-U Tunnel
LTE network
: The SGSN establishes a user plane tunnel (GTP-U tunnel over an S12 interface) directly between
the RNC and the S-GW, using an Update PDN Context Request toward the S-GW.