I seem to recall a router that had two WAN connections and a dial-up connection. I think it did some sort of load balancing between the two WAN lines and switched to dial-up if both WAN lines failed. I don't remember who made it, but I THOUGHT they were sold to Symantec, but I can't find it on their website. I'm not sure how it worked, but I have the impression that it routed web page requests out the two WAN lines and then put them back together on the LAN side. Since most web pages contain (too many) lots of images, the image loading was split between the two WAN lines, so the user saw faster loading. It did not, as far as I know, try to spread out packets from the same transaction, but, instead, spread out the transactions (file requests, etc.). I was considering buying one a few years ago, but never got around to it.
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