Can I separate the computer from the router?

Comcast cable modems are locked to the MAC of the computer that cable modem service is initially activated on. Thus, your computer needs to be connected directly to the cable modem at time of cable modem service activation. So Comcast is correct when they say "no". HOWEVER . . .

If you get a Netgear (or other good) brand Wireless router, it will gladly spoof the MAC of the computer. The procedure would be . . . hook up cable modem directly to computer with ethernet cable, get it working OK, test it out by using the Internet for a while. Then power everything down, unplug cable modem (power). Now hook up wireless router (using 2 ethernet cables) between cable modem and PC. Power up cable modem (wait a few minutes), power up router (wait a few minutes) and power up computer. This will allow the router to program itself for your Comcast connection, and to spoof the identity of your computer. If the router doesn't pick up the MAC address to spoof automatically, you might have to enter it manually. Then test computer to see if it is still working OK. If so, use the computer to log into the router to configure a wireless connection. TEST the wireless connection. Once wireless connection is working, you can unplug the computer. THE DOWNSIDE TO THIS . . . if you ever lose power, you might need to re-program the router. This will require the computer to be hooked up (with ethernet cable) to the router again. So if you try this, I'd suggest running the cable modem and router off of a UPS.

So it's gonna be kind of a pain in the butt, but it SHOULD work, if you are willing to jump through the hoops to make it work. Don't expect help from Comcast, though.

Why do you say DSL is unappealing? A good DSL connection is more reliable than a good Cable modem connection. In fact, your connection speed with DSL will be more consistent. During peak usage hours, DSL is faster. I'd gladly go back to ADSL, but it would mean having to have a phone line installed, and paying monthly service charges for a land line that is only used for DSL. (we ditched our land line for cell phones a long time ago) But if you HAVE a land line anyway, DSL is a great option. -Dave

Off the top of my head, I can see two possible concerns:

1. Are both downstairs and upstairs part of the same dwelling unit? If they're not, that's a big problem regardless of whether someone is a family member or not.
2. If the computer cannot be connected directly to the modem, you would not be able to get customer support. Support cannot take your word for it that there is nothing wrong with the wireless connection, or even a router. Nor do they have the training to troubleshoot any problems created by these third-party devices.

Now the first reason is enough to deny you service. The second is only enough to deny you support. (However "support" in this case would involve installation.)

To overcome the second issue, the computer (or a computer) should be temporarily placed in a location near the modem. Once installation is complete, you are then free to add a router, or even a wireless router, and move the computer to anywhere you wish within your dwelling unit. (You would not have the right to provide service to a computer located in another dwelling unit, regardless of the familiar relationship of it's user.) However, if you ever need to call support, you may need to have the computer connected directly to the modem in order for complete troubleshooting to be done.

Trying to steal the thunder from Arnold, "TomC" on Tue, 16 Nov 2004 13:48:51 -0500 spoke:

Have the computer downstairs when Comcast does the install, then move it back upstairs when they're done.

You do not have to spoof the MAC address of the computer in the router. You do need to power-cycle the modem when switching which device you connect to it. You can swap devices all you want, as long as you don't attempt to use a hub or a switch to have both (all) of them connected at the same time.

This is one of the benefits of the "bottom-up" provisioning that Comcast, and many other cable operators now use. There are only a few cable operators out there that now require you to either call them to change a MAC address, or spoof a MAC address in order to change the device connected.

The original poster is in Sacramento. Sacramento once was Comcast before being sold to AT&T Broadband. (Actually, it was a trade for Royal Oaks, MI.) That trade took place when AT&T Broadband was still using @Home, so when @Home went under, Sacramento went to ATTBI, so they were converted to bottom-up provisioning from the beginning, and never had to deal with the system used by Comcast HSI between the time they left @Home, and when they acquired AT&T Broadband, along with the account technology. Comcast customers in markets that never were ATTBI had at least two different provisioning systems in use before the ATTBI bottom-up system was deployed to them.

So at one time, some Comcast customers may have needed to spoof a MAC address, but they do not now. Any ATTBI customers who think they had to spoof a MAC address after ATTBI took over from @Home had some other issue going on. Most probably just didn't power-cycle their modem, or they just happened to try to do something at the same time back-office work was going on that would have delayed the propagation of a change.

But the bottom line is that at this time, no Comcast customer should need to spoof a MAC address. (Or at least not as a permanent fix.)

Thanks, everyone! This is exactly what I needed. Very helpful.