address and subnet mask. If the WAN interface does not have a suitable subnet mask that is usable, for example when using PPP or PPPoE, the DHCP subnet configuration will default to a class C subnet mask.
1.Select either User Configured PC or an IP address displayed in the selec- tion window (these are the IP addresses currently being served to com- puters on your LAN.)
If you select “User Configured PC”, you must then configure a local PC to have the pub- lic WAN IP address.
2.Click Enable.
You will be reminded to restart the Router.
3.Click the Restart Router link and confirm the restart when prompted.
Once configured, the passthrough host's DHCP leases will be shortened to two minutes. This allows for timely updates of the host's IP address, which will be a private IP address before the WAN connection is established. After the WAN connection is established and has an address, the passthrough host can renew its DHCP address binding to acquire the WAN IP address.
A restriction
Since both the Router and the passthrough host will use the same IP address, new ses- sions that conflict with existing sessions will be rejected by the Router. For example, sup- pose you are a teleworker using an IPSec tunnel from the Router and from the passthrough host. Both tunnels go to the same remote endpoint, such as the VPN access concentrator at your employer’s office. In this case, the first one to start the IPSec traffic will be allowed; the second one – since, from the WAN, it's indistinguishable – will fail.
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