Can comcast be used as a backup for a T1 to keep your internet connection from going down?

Yes you can have Comcast as a backup for redundancy. However don't think you'll be paying the same rate as home users do for their internet connection. You'll have to use their business line and pay the business rates. I would check with them to see if it's available in your area.

For the IP issue once you have a backup line in place you can configured your router and server to use the secondary IP if data cannot pass through the primary(your existing T-1)

Hope this helps

Yes you can use comcast as a back up for your T1. You will need a router capable of failover. Sonic Wall makes some great products.

I think a better suggestion is to find a tier 1 co-lo facility to host your on line store. That places it in a secure computing facility that is adjacent to the internet backbone.

AT&T is setting the standard for a new era of communications and entertainment. It is the largest telecommunications company in the United States and one of the largest in the world. AT&T has just joined forces with Bell South, SBC, and Cingular to become the New AT&T.

AT&T offers Fast Access DSL, and Celluar services

http://att.riveroffers.com/?crid=149255

http://www.cellphoneriver.com/?crid=149255.

http://dishnetwork.riveroffers.com/?crid=149255

If you current provider goes down from time to time, COMPLAIN. Theres no excuse, especially for how much money they charge for T1.

If they refuse to try to fix it, bin them and get a different provider.

Make sure you tell them that if they don't fix it, you're leaving them, it'll make them work harder to fix it, they want you as a customer, so if they think you're going to leave, they'll work hard to fix the problem.