Full Disclosure mailing list archives
Re: DNS and NAT (was: DNS and CheckPoint)
From: Valdis.Kletnieks () vt edu
Date: Fri, 11 Jul 2008 11:51:42 -0400
On Fri, 11 Jul 2008 11:01:33 EDT, Thomas Cross said:
Thanks for testing this. A number of other readers wrote me privately confirming your result with linux ipchains. I'm not sure what ipchains does when it encounters a collision, but in general I think this is a good strategy. You'd have to have many thousands of simultaneous UDP transactions in order for randomly selected source ports to be colliding frequently enough for it to present a substantial problem.
Birthday paradox strikes again. With 64K source ports, you'll have collisions over 1% of the time at only 1024 in use. With 8K in use, you're hitting collisions 12% of the time.
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Current thread:
- DNS and NAT (was: DNS and CheckPoint) Thomas Cross (Jul 10)
- Re: DNS and NAT (was: DNS and CheckPoint) Riad S. Wahby (Jul 10)
- Re: DNS and NAT (was: DNS and CheckPoint) Thomas Cross (Jul 11)
- Re: DNS and NAT (was: DNS and CheckPoint) Valdis . Kletnieks (Jul 11)
- Re: DNS and NAT (was: DNS and CheckPoint) Riad S. Wahby (Jul 11)
- Re: DNS and NAT (was: DNS and CheckPoint) Marco Slaviero (Jul 16)
- Re: DNS and NAT (was: DNS and CheckPoint) Thomas Cross (Jul 11)
- Re: DNS and NAT (was: DNS and CheckPoint) Riad S. Wahby (Jul 10)
- Re: DNS and NAT (was: DNS and CheckPoint) Ryan McBride (Jul 16)
- <Possible follow-ups>
- Re: DNS and NAT (was: DNS and CheckPoint) Elazar Broad (Jul 11)
- Re: DNS and NAT (was: DNS and CheckPoint) Thomas Cross (Jul 14)