EchoLink FAQ
Using EchoLink on more than one computer.
By: Rob Rude (AJ0C)Background
EchoLink requires a unique IP in order to communicate with a computer. Typically, cable companies and DSL service providers allocate only one Internet address to an entire household, in which there may be several computers.
A router (as used in the home) is a device which allows more than one computer to communicate over a single connection, such as a connection to the Internet. Routers have become more common in homes as home networks and high-speed connections, such as cable or DSL, have become more popular. The router must decide which computer should receive each packet of data which comes in from the Internet.
Single Computer Solution (a.k.a., One-of-Many)
Port Range Forward directs the router to route all packets for a given Port Range to a specific computer.
I use Linksys routers for my home network and prior to changing to Port Triggering they were configured for Port Range Forward. This is a screen shot of the configuration page.
In the above example all UDP packets received by the router from the Internet port are routed to the computer assigned the IP Address 192.168.3.102. Port Range Forward requires Static IP Addresses to be assigned since the router must know the exact IP Address of the computer that is supposed to receive the forwarded data.
Any-of-Many Solution
Port Triggering: Some routers implement a "smart" forwarding scheme which tries to direct data to the computer which is most likely to use it, based on requests each computer has recently made. If you expect to use EchoLink on any of several different computers at different times, you may wish to try this option.
NOTE: You can not use Port Range Forward and Port Triggering of the same ports at the same time. If you were previously using Port Range Forward you must disable it for the EchoLink ports that you are going to configure for Port Triggering.
I use Linksys routers for my home network and they are configured for Port Triggering. This is a screen shot of the configuration page.
In the above example the router is instructed to monitor Local Area Network (LAN) ports 5198 through 5200 for activity. Detection of activity TRIGGERS the router and tells it to forward all Internet port activity on ports 5198 to 5199 to the IP Address of the computer that "Triggered" the router. Since forwarding is directed to the IP Address of the computer that triggered the router DHCP (Dynamic Host Control Protocol) may be used in lieu of Static IP Addresses.
NOTE: You CAN NOT use more than one computer for EchoLink at the same time. The last computer to "TRIGGER" the router is the one that will assume EchoLink connectivity control. You may use any of your computers, but you must only use one computer at a time for EchoLink.
For more information, including step-by-step solutions for several popular routers and firewalls, see the Firewall Solutions page on the EchoLink Web site.
Last Modified: Friday, 15-Aug-2008 15:29:48 EDT