North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Computer systems blamed for feeble hurricane response?
On Tue, Sep 13, 2005 at 05:54:03PM -0400, Steven M. Bellovin wrote: > In message <[email protected]>, 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 ----------------------------------------------------------------------- This message is not an official statement of OSIS Center policies.
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