User's Manual Part 1

User’s Guide Chapter 7 – Reference Manual
Network Interface | Tunnels | GRE Client for VPN
GRE (Generic Routing Encapsulation) tunnel is one of the solutions for tunneling private network over
the TCP/IP connection (e.g. PPTP, L2TP, PPPoE). GRE tunnel does not use encryption. It only
encapsulates data and sends it over the Internet. So the administrator should take care that no
unencrypted private information is going through the GRE tunnel. By default the GRE tunnel is
disabled on the AC:
Figure 82 – GRE Tunnel
See the following example to understand GRE settings.
Example:
P-560
GRE Serve
r
Internet
Net A
Net B
192.168.82.0/24
WLAN:
192.168.3.0/24
GRE Device IP:
211.139.210.168
LAN:
192.168.82.16
WAN:
211.139.210.123
GRE Tunnel
NMS:
IP: 192.168.82.137
Router: 192.168.82.16
Figure 83 – GRE Tunnel
For example, there are 2 internal networks: network A and B, and intermediate network - Internet.
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