3Com OfficeConnect User Manual page 63

making the tunnel more secure but slowing data transfer. To
enable perfect forward secrecy ensure that the Use Perfect
Forward Secrecy box is checked. To keep the same key for the
length of a connection leave the box unchecked.
Click Apply to save your changes or Close to return without
saving.
IPSec Connections using Gateway to Gateway
If you have selected IPSec as a Tunnel Type and Gateway to
Gateway as a Connection Type, enter the following values:
Remote IPSec Server ID — The ID of the remote server. In the
case of another 3Com Secure Router this is the This Router's
ID field on the VPN Mode page.
Remote IPSec Server Address — enter the Internet IP address
or DNS name of the remote device (Figure 62). A DNS name
may only be entered if it is the same as the Remote IPSec
Server ID in the box above.
Remote Network address — enter the LAN IP address of the
remote network. This is the first IP address of a subnet, one
below the first address available for use.
Figure 62 IPSec Connection - Gateway to Gateway
If the remote device has a LAN IP address of 192.168.1.1 and a
subnet mask of 255.255.255.0 then the LAN IP address of the
remote subnet is 192.168.1.0.
The devices must be configured with LAN IP address ranges that
do not overlap.
Remote Subnet Mask — this is set as 255.255.255.0 as
default.
Tunnel Shared Key — this is the password for the connection
and is a combination of letters, numbers and punctuation and
can be up to 64 characters in length.
If you are creating a Gateway to Gateway connection you have
no need to remember the Tunnel Shared Key once the tunnel is
established and do not have to make the key a memorable
password.
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