I have my Comcast cable connection running thru a router (which is an Airlink wireless router, however, my computer is connected to the router through a LAN cable, not wireless). I need an IP that will work for transfering files over AIM, etc.. But the router gives my computer a 192.x... IP. How can I (without paying extra of course) make it so that my computer is assigned an IP (which should be in the 66.x range) when it is connected thru the router? Removing/replacing the router is not an option, but I also need to have a workable IP on my computer. I have an AirLink wireless router. Thanks a lot. I will be eagerly awaiting any responses!

I don't think that you understand how the router works. There are two addresses involved. As you said, the router assigns an address to your PC (192...). But the router (more specifically the cable modem) is assigned an IP by Comcast. The IP assigned to by Comcast may be static (never changes) or assigned using DHCP (it changes periodically). But the IP assigned by Comcast to your cable modem is the IP that the rest of the world sees when your computer communicates with the internet. And, as you said the router assigns a 192 address to your computer. When you use AIM from your computer, AIM sends messages to the AIM server telling it that your address is 192.whatever. All of those messages go thru the router and the router changes the 192.whatever address to the IP address assigned to you by Comcast. So when the message arrives at the AIM server, AIM sees your address as the Comcast address, not the 192 address. So when AIM sends a message back to you, it sends the message to the Comcast address which gets the message to your house, to the cable modem and to the router. The router switches the IP address back to the 192.x address and sends it on to your computer. Thus, you are communicating to the internet world and the internet world is seeing the Comcast address, not the 192.x address. Why do all of this, you might ask. Well, if you have only one computer, then this is overkill. You can get rid of the router and just connect your computer to the cable modem (ignoring the firewall considerations that most routers provide). The reason that the router does this IP magic manipulation is so that you can have multiple computers hooked to the router and sharing the one cable modem. If you have four computers, but didn't have a router, you'd have to have (and pay for) four IP addresses from Comcast. But with the router between the computers and the cable modem, the outside world sees only one IP address even tho there are four computers. The router allows each of the four computers to have different 192.x addresses, but it does the switching back and forth as messages go in and out of the IP address between the 192.x and Comcast IP. (This switching of IPs also includes the use of port numbers, but we'll skip that part for now). So, the point is, unless you have some abnormal situation, you have a workable IP, its the one assigned to you by Comcast and the router will handle the translation between the 192. IP and the Comcast IP.

Well said Don. Comprehensive and clear. Give a man a fish and you feed him for a day. Teach him to fish and you feed him for life.

I am sure a 'Thank You' for Don's extended effort will be forthcoming soon. Peter (Alert me if you want a reply)

Thanks. I should add that, in looking back, I'm not sure if the Comcast IP is assigned to the cable modem or the router. But for the purpose of this discussion, it doesn't matter.

Don, I do sincerely thank you for your assistance. I understood the concept of interal IP assignment, but I appreciated very much your thourough explanation. The issue I had was with unblocking udp/tcp ports, although I didn't realize THIS was the issue at the time I posted the question. It doesn't really matter anyway though as my router keeps dropping the internet connection. Is it perhaps because I bought an Airlink wireless router and my roomate uses an Airlink wireless card to recieve the signal? Airlink+ seems to suck, but i'm not sure. Any comments? Thanks again Don et al. -TiM

This could be from anything ,specially if you are running XP which seems to have a number of wireless issues . I would shutoff the Windows Zero config utility and use the client that came with the wireless nic . SP2 adds even more fun to the pot .