How do I connect remotely?
 

So I have setup a dyndns.org account and I can remotely access my router - WRT54G v5 using DD-WRT micro v23 SP2 . I have setup up an internal network with 2 computers at the moment, both with assigned IP addresses.

Computer 1 is a linux computer (FC5) and Computer 2 is a Windows MCE computer. Can someone direct me as to how I can go about setting up being able to access Computer 1 remotely - both through using the CLI and a GUI. I will be looking to access from an XP based computer.

using port forwarding

So do I assign some port, say 100. Then use a VPN program to connect to user.dyndns.org:100?

You will need to setup Port Forwarding on your router so that some public port will forward to either private IP address and port 22(ssh) for CLI to that machine(provided that you have the sshd service running) and/or public port that will forward to the private IP address and VNC (not VPN) private port that you have configured in your vncserver(provided that it is running) on that machine.

example:
remote.yourdomain.com:10000 would forward to your Linux machine's IP and ssh port 10.1.1.1:22

You can then access either port as you mentioned above via a remote connection software. A popular remote terminal software for Windows is TeraTerm Pro, and for remote desktop access, you can use VNC, of which there are various flavors (I prefer TightVNC for speed).

You can do the same steps to access your Windows PC via VNC also, just by configuring a different public port to forward to it's private IP address and port.

Is a public port one on my router so to say. By that do I open a port to forward through the router GUI and assign that port to the IP address of Computer 1? And then besides that port I also need to open port 22 on Computer 1 using iptables?

yes, you browse into your WRT54G, set the port forwarding. Normally you have few parameter.
-What port number you router want to listen on WAN interface for port fowarding
-what server ip address you want to redirect to from internet guess.
-what destination port on that server(This is necessary if you want to have more than 1 server with same port number, like http allow remote access).

KS