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

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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