The topic you are curious about is called peering: https://en.wikipedia.org/wiki/Peering https://en.wikipedia.org/wiki/Peering While Comcast doesn't have to p

The topic you are curious about is called peering: https://en.wikipedia.org/wiki/Peering https://en.wikipedia.org/wiki/Peering While Comcast doesn't have to peer with you directly, there is nothing stopping the ISPs that peer with Comcast to peer with you as well.