Senor Barborito wrote:

This relieves AOL of having to support the bandwidth of maintaining a file-transfer proxy service. Since the AIM client on Host A sends packets to Host B that appear (to Host B's firewall) to be part of Host B's second connection with AOL's IM servers (thanks to AOL's IM servers passing the sequence/IP combo with which to forge the packet to Host A on the first connection to Host A), they pass through the firewall and to Host B, where the AIM client grabs the data and forges a similar packet (with the sequence/IP combo mirroring Host A's second connection to AOL's IM server).

..

I really need someone who understands basic IP routing better than I do to tell me if this is all a pipe dream. I suspect it is, but it would be extermely cool if AOL could tunnel a direct connection through two firewalls set to blackhole like this.