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Re: Computer systems blamed for feeble hurricane response?

  • From: Joseph S D Yao
  • Date: Tue Sep 13 17:59:54 2005

On Tue, Sep 13, 2005 at 05:54:03PM -0400, Steven M. Bellovin wrote:
> In message <20050913212312.GM16110@core.center.osis.gov>, Joseph S D Yao writes
> :
> >On Tue, Sep 13, 2005 at 04:56:58PM -0400, Joseph S D Yao wrote:
> >> On Tue, Sep 13, 2005 at 04:28:41PM -0400, Steven M. Bellovin wrote:
> >> ...
> >> > Telnet options, and for that matter speed, happen after the 3-way 
> >> > handshake.  We're not getting that far.
> >> > 
> >> > 		--Steven M. Bellovin, http://www.cs.columbia.edu/~smb
> >> 
> >> Steve, I defer to your expertise, as always.  ;-]
> >
> >
> >Nevertheless ... I went looking for comments on how this was being done,
> >and found the following specualtion by a small number of different
> >people.
> >
> >"SEF [is] unique in that it can detect what appear to be telnet
> >connections to Port 25 and drop the connection. This is probably because
> >telnet connections send one character at a time whereas real SMTP
> >clients send all the strings at once."
> >
> >This would not require the 3WH, ISTM.
> 
> Sure it would -- until the 3-way handshake, there's no application data 
> flowing, and hence no characters being sent one at a time.

Right.  Doh.  Me go home lie down rest.

> We'll leave to another mailing list the question of what security 
> benefit there is to such a feature...

;-)

-- 
Joe Yao
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