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Re[4]: SYN floods (was: does history repeat itself?)

  • From: Pat Calhoun
  • Date: Mon Sep 16 08:45:47 1996

     Curtis,
     
        As I stated in my previous e-mail, we could do this by adding this 
     to our release notes in our product, describing the problem and 
     advising against not taking measures. However, this would only apply 
     to our customers, which I would venture to say that most already do 
     understand the problem :).
     
        However, if there is anything that I can do to help, please let me 
     know since I take the threat of the "imminent death of the internet" 
     very seriously.
     
     
     Pat R. Calhoun                                e-mail: [email protected] 
     Project Engineer - Lan Access R&D                phone: (847) 933-5181 
     US Robotics Access Corp.
     
______________________________ Reply Separator _________________________________
Subject: Re: Re[2]: SYN floods (was: does history repeat itself?) 
Author:  Curtis Villamizar <[email protected]> at Internet 
Date:    9/12/96 1:44 PM
     
     
     
In message <[email protected]>, 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: [email protected] 
>      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" <[email protected]> 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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> Subject: Re: SYN floods (was: does history repeat itself?) 
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To: [email protected] (Pat Calhoun)
cc: [email protected], "Perry E. Metzger" <[email protected]>
Reply-To: [email protected]
Subject: Re: Re[2]: SYN floods (was: does history repeat itself?) 
In-reply-to: Your message of "Mon, 09 Sep 1996 13:19:18 CDT."
             <[email protected]> 
Date: Thu, 12 Sep 1996 13:44:04 -0400
From: Curtis Villamizar <[email protected]>
Sender: [email protected]