Gtp Tunnel With Ggsn (Gtpv1) - Ruckus Wireless SmartCell Gateway 200 Reference Manual

GTP Tunnel with GGSN (GTPv1)

Gn interface is used in controlling the signal between the SCG and GGSN as well
as for tunneling end user data payload within the backbone network between both
the nodes.
GTP transmits user data packets and signaling between SCG and GGSN. GTP
encapsulates traffic and creates GTP tunnels, which act as virtual data channels for
transmission of packet data between SCG and GGSN. A GTP tunnel is established
between SCG and GGSN through create PDP context procedure for a data session
initiated from UE.
A GTP tunnel is identified by a pair of IP addresses and a pair of GTP Tunnel End
Point Identifiers (TEIDs), where one IP address and TEID is for the SGSN and the
other is for the GGSN. TEID is a session identifier used by GTP protocol entities in
the SGSN and in the GGSN.
The two TEID are defined each for GTP-C and GTP-U. GTP-U is a tunneling
mechanism that provides a service for carrying user data packets. On both planes,
a GTP header encapsulates the data package, called G-PDU, and a path imple-
mented by UDP/IP is used as bearer of the GTP traffic. GTP-C is a tunnel control
and management protocol and is used to create, modify and delete tunnels.
The SCG supports the following categories of GTP signaling traffic:
• Path management messages - The main purpose of these messages is to
supervise an UDP/IP path to ensure that connectivity failure can be detected on
time. This is managed by frequently sending GTP echo request or response
packets between the SCG and the GGSN.
• Tunnel management messages - These contain messages that establish, modify
and release GTP tunnels.
Figure 4 shows the message flow between the SCG and the GGSN for establishing
a GTP tunnel.
SmartCell Gateway 200 Tunneling Interface Reference Guide for SmartZone 3.4.1, 800-71380-001 Rev A
Figure 5 shows the Gn interface flow.
Core Network Protocols
Core Network Protocols
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