[4325] in North American Network Operators' Group
Re: Re[2]: SYN floods (was: does history repeat itself?)
daemon@ATHENA.MIT.EDU (Curtis Villamizar)
Thu Sep 12 13:47:42 1996
To: pcalhoun@usr.com (Pat Calhoun)
cc: nanog@merit.edu, "Perry E. Metzger" <perry@piermont.com>
Reply-To: curtis@ans.net
In-reply-to: Your message of "Mon, 09 Sep 1996 13:19:18 CDT."
<233128C0.3000@usr.com>
Date: Thu, 12 Sep 1996 13:44:04 -0400
From: Curtis Villamizar <curtis@ans.net>
In message <233128C0.3000@usr.com>, Pat Calhoun writes:
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> Perry,
>
> This is actually quite simple to implement on Dial Access Routers,
> and obviously this is the best place to add the filtering.
>
>
> Pat R. Calhoun e-mail: pcalhoun@usr.com
> Project Engineer - Lan Access R&D phone: (847) 933-5181
> US Robotics Access Corp.
I agree with you completely -- sort of. Only problem is there are
thought to be some 3,000 dial access providers. Many of them barely
know what a TCP SYN is, let alone why they need to block ones with
random source addresses and how. Unless of course you are
volunteering to explain it and help them. Thanks in advance. :-)
Curtis
> ______________________________ Reply Separator ______________________________
> ___
> Subject: Re: SYN floods (was: does history repeat itself?)
> Author: "Perry E. Metzger" <perry@piermont.com> at Internet
> Date: 9/9/96 1:19 PM
>
>
>
> Re: SYN floods
>
> PANIX, a large public access provider in New York, was badly hit with
> SYN flood attacks from random source addresses over the last few
> days. It nearly wrecked them.
>
> I think its time for the larger providers to start filtering packets
> coming from customers so that they only accept packets with the
> customer's network number on it.
>
> Yes, its a load on routers. Yes, its nasty for the mobile IP weenies.
> Unfortunately, the only known way to stop this. Many TCPs go belly up
> as soon as they get SYN flooded -- its a defect in the protocol
> design, and other than Karn style anti-clogging tokens ("cookies")
> being put into a TCP++ and mass implemented worldwide soon, the only
> reasonable way to stop this sort of terrorism is provider filtering.
>
> Perry
> --IMA.Boundary.388702248
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> To: nanog@merit.edu
> Subject: Re: SYN floods (was: does history repeat itself?)
> In-reply-to: Your message of "Mon, 09 Sep 1996 12:47:13 EDT."
> <199609091647.MAA01458@tomservo.mindspring.com>
> Reply-To: perry@piermont.com
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> Date: Mon, 09 Sep 1996 13:19:02 -0400
> From: "Perry E. Metzger" <perry@piermont.com>
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