Can anyone tell me if it's possible to set the following up?

My boss wants to be able to connect to his store's inventory computer (a linux machine) from his home PC. He used to be able to telnet in through the router which had port forwarding set up, pointing him right into the IP of the linux box.

Then, if I understand this correctly, Comcast recently changed our (external?) IP to a static one, and my boss can no longer connect from home, even after changing the IP setting in his telnet program. Comcast told me that this is basically "just the way it is" and that due to the nature of the IP change they've made (it used to be "persistent," now it's static?), telnetting in through the router from outside is no longer possible.

I was told that there is other remote access software available (something like Go To My PC) that might get it done, but I can't find anything that indicates the ability for a Mac or a PC to connect remotely to a linux machine.

Does anyone know if such a thing is possible?

Huge, gigantic amounts of thanks in advance if anyone can give me any leads...

Welcome to LQ.

I assume you mean it's changed to dynamic? If it was static then it wouldn't change.

You may want to try using a dynamic dns service to track IP changes:
http://www.no-ip.com/

I'd also suggest switching to ssh rather than telnet as it is much more secure:
http://wiki.linuxquestions.org/wiki/Telnet_and_SSH

Thanks! I'll look into using Putty for ssh instead of telnet (I believe my boss was already using Putty, so this should be easy).

The static/dynamic thing is confusing, because obviously, as you say, static means it stays the same, but I swear the Comcast support person told me that the IP had "changed to static."

Thanks for the quick reply!