Each device on the local network has its own unique local IP address (192.168.1.101, in the case of my KOB server), but they all have the same external IP address on the global internet. This external address is assigned by the internet service provider. Although the address may change from time to time, in my experience it tends to remain stable for several months or more. By going to checkip.dyndns.com, I can see that the current (global) IP address for my server is 22.214.171.124.
It's the job of the router to receive incoming internet packets that are sent to its IP address (126.96.36.199 in my case) and redirect them to the appropriate computer on the local network (192.168.1.101 for my server). Each internet packet contains a port number in addition to an IP address, and the router uses this port number to determine which computer on the local network to send the packet to. KOB packets use port 7890, and HTTP packets use port 80, so we need to set up the router's port forwarding table to associate those port numbers with the server's local IP address.
My local network uses a Netgear router. Here's how I go about configuring it:
- Log in to the router using the web browser on any computer connected to the router (directly or wirelessly).
- Go to the port forwarding page.
- Add two new port forwarding services:
- service name: MorseKOB
service type: UDP
starting port: 7890
ending port: 7890
server IP address: 192.168.1.101 (or whatever the server's actual IP address is)
- service name: HTTP
service type: TCP
starting port: 80
ending port: 80
server IP address: 192.168.1.101 (or whatever)
Note: It's not apparent from the above screen that the MorseKOB service is set up for UDP packets, and the HTTP service for TCP.
Address assignment range
When I picked 192.168.1.101 for the server's local IP address, I chose it so that it wouldn't conflict with any addresses that the router might assign to other computers on the local network. How did I know this? By going to the router's LAN IP setup page:
From this screen, I can see that the router's DHCP service assigns addresses in the range 192.168.1.2 to 192.168.1.51. The IP address I picked for my server, 192.168.1.101, is outside this range, so I know it's safe from any possible conflicts.
Now it's time to see if KOB users can access your server over the Internet, using the server's global IP address:
- Using a web browser on your server, go to checkip.dyndns.com and make a note of your server's global IP address. At the moment mine is 188.8.131.52, but yours will be different.
- Using a computer at some other location, run the same tests as in the previous sections (see IP address), but this time set up MorseKOB to access the server at its global IP address (using the Tools > Debug menu).
For this test, you can take a laptop to a nearby coffee shop or public library and use their internet connection to run MorseKOB with your server, or you can ask another KOB user to do the test. Please contact me if you need help in this regard.
Once you have your router configured correctly, you can proceed to the final step: setting up a DynDNS account.