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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: TCP receive window set to 0; DoS or not?
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Jim Shankland wrote: > To address the "DoS" question, I don't see how this protocol violation > enables a DoS attack. More likely, it's simply somebody's buggy > TCP stack misbehaving. That "somebody" is unlikely to be Windows, MacOS, > FreeBSD, or Linux. My money is on some flavor of $50 NAT/"home router" > box. The part where it becomes a DoS is when they tie up all the listeners on a socket (e.g. apache), and nothing happens for several minutes until their connections time out. Whether intentional or not, it does have a negative effect. It's insidious in that it leaves no traces in the application logs; in particular, apache never logs anything because they never complete a transaction (it logs when they finish). - -- The whole point of the Internet is that different kinds of computers can interoperate. Every time you see a web site that only supports certain browsers or operating systems, they clearly don't get it. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2.2 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFFAeGPPlSPhv5tocwRAgSVAJ4qGEo/aR4CMaBcnsu+H6DyGpN7iACfcMAM FGvZWaAY2GYVSDLf37YUwbw= =RZ/F -----END PGP SIGNATURE-----
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