Forum Overview :: Motherfucking News :: Don't use ACKs

[quote name="Senor Barborito"][quote name="bastage"][quote name="Senor Barborito"]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.[/quote] So where would the ACKs go ..? Back to AIM HQ ..? (Since he's the 'source' ..) Like I've said a few times, what you're talking about it is not impossible but I think it would be too kludgy to be effectively used for something like a file transfer. (How would window sizes be effectively negotiated ..? How about error correction ..? etc.) [/quote] re: ACK - One suggestion is to use UDP for the 'new' connection and manually implement it yourself, pseudo-'ACK'ing to the person sending you the file. Let AIM handle it internally the way online games do (very low-bandwidth sequencing by hand, relatively infrequent worldstate connection-integrity-sensitive-variable checks). I say this because I'm not entirely certain control of the network stack is fine enough in Windows to allow one to manually suppress outgoing ACKs - even if it weren't AOL has cut down on the bandwidth they get hit with so much it's a huge win. And yes, it would probably be too kludgy (again, egress filtration of IP?). Glad you think it's at least maybe possible , though - coming up with little ideas like this is probably my favorite thing in the whole world, even if it's not really practical IT ENABLES THE SUPPOSEDLY IMPOSSIBLE AND IS THEREFORE ITS OWN JUSTIFIED ENDS BLAH BLAH BLAH etc. [/quote]