KB 77

Port forwarding with Efficient/Flowpoint Router

Article:77
Created:2001-12-24 10:07:27
Categories:
  routing
  DSL

Question or Symptom

DSL customer is using private IP space on their lan and using NAT on their Flowpoint router. This allows traffic from their private IP space to be routed to the Internet, and the Flowpoint router will give its IP address as the IP address for all traffic leaving through the router. The problem comes in when the user has an application, such as a web server, running on the LAN that they want visible from the outside world. My experience was with a gamer who needed people to have an IP address for his machine so they could join games he was hosting.

Resolution

Find out if the application always uses the same TCP or UDP port. If so, port forwarding may solve the problem. It works by telling the router to pass any traffic addressed to the routers IP AND a certain port to a specific IP address on the Lan. This machine's IP address will have a private space IP address that would ordinarily not be available from the outside world.

Procedure is look up the client's router's password in and WAN IP in x-mod. Then telnet to the router, login, and issue the command for port forwarding:

system addserver <LAN server IP address> <protocol> <port>
 

save

Example:

system addserver 192.168.254.2 tcp 2346
save
 

You must type "save" if you want this configuration to still be in place when the router is rebooted.

Related KB articles

 KB 110 How do I set up the Flowpoint (Efficient) router to be an MS VPN server?