I have seen many colocation companies offering something called "Blended Bandwidth" and that makes me wonder how do they do it?
Here is my example. If I would get two internet services, from ISP-A and ISP-B. They both would give me IP addresses to use on their own network. If one would fail, I would not be able to use the IPs from ISP-A on the connection of ISP-B.
I know, to use simply private addresses behind a router... But that is not how they do it.
So any idea?