Serving Gateway Overview
Supported Logical Network Interfaces (Reference Points)
The following figure displays the specific network interface between a Serving Gateway and other E-UTRAN network
devices.
Figure 3.
E -U T R A N
E P C
The S-GW provides the following logical network interfaces in support of the E-UTRAN/EPC network:
S4 Interface
This reference point (not shown in the figure above) provides tunneling and management between the S-GW and an
SGSN.
S5/S8 Interface
This reference point provides tunneling (bearer channel) and management (signaling channel) between the S-GW and
the P-GW. The S8 interface is used for roaming scenarios. The S5 interface is used for non-roaming.
Supported protocols:
Transport Layer: UDP, TCP
OL-22986-01
S-GW Interfaces in the E-UTRAN/EPC Network
S ig n a lin g In te rfa ce
B e a re r In te rfa ce
eN odeB
M M E
S 1 1
S 1 -U
Cisco ASR 5000 Series Serving Gateway Administration Guide ▄
G xc
S -G W
S 5/S 8
Network Deployment(s) ▀
P C R F
P -G W