Geneko GWR High Speed Router Series, User Manual

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User Manual
Geneko GWR High Speed Router Series
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GRE Tunnel configuration between GWR-HS Router and third party router
GRE tunnel is a type of a VPN tunnels, but it isn't a secure tunneling method. However, you can encrypt
GRE packets with an encryption protocol such as IPSec to form a secure VPN.
On the diagram below (
Figure 67
) is illustrated simple network with two sites. Idea is to create GRE tunnel
for LAN to LAN (site to site) connectivity.
Figure 67 – GRE tunnel between Cisco router and GWR-HS Router
GRE tunnel is created between Cisco router with GRE functionality on the HQ Site and the GWR-HS Router
on the Remote Network. In this example, it is necessary for both routers to create tunnel interface (virtual interface).
This new tunnel interface is its own network. To each of the routers, it appears that it has two paths to the remote
physical interface and the tunnel interface (running through the tunnel). This tunnel could then transmit
unroutable traffic such as NetBIOS or AppleTalk.
The GWR-HS Router uses Network Address Translation (NAT) where only the mobile IP address is visible to
the outside. All outgoing traffic uses the GWR-HS Router WAN/VPN mobile IP address. HQ Cisco router acts like
gateway to remote network for user in corporate LAN. It also performs function of GRE server for termination of GRE
tunnel. The GWR-HS Router act like default gateway for Remote Network and GRE server for tunnel.
1. HQ router requirements:
•
HQ router require static IP WAN address,
•
Router or VPN appliance has to support GRE protocol,
•
Tunnel peer address will be the GWR-HS Router WAN's mobile IP address. For this reason, a static mobile
IP address is preferred on the GWR-HS Router WAN (GPRS) side,
•
Remote Subnet is remote LAN network address and Remote Subnet Mask is subnet of remote LAN.