Re: [ftpext] Discouraging use of TCP "urgent data"

"William F. Maton" <wmaton@ottix.net> Thu, 23 September 2010 23:23 UTC

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Date: Thu, 23 Sep 2010 19:23:36 -0400
From: "William F. Maton" <wmaton@ottix.net>
To: Fernando Gont <fernando@gont.com.ar>
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References: <4C98B731.2030802@isode.com> <Pine.LNX.4.64.1009211253500.29844@iskra.ottix.net> <4C9A056C.9010808@gont.com.ar>
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Cc: Alexey Melnikov <alexey.melnikov@isode.com>, ftpext@ietf.org
Subject: Re: [ftpext] Discouraging use of TCP "urgent data"
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On Wed, 22 Sep 2010, Fernando Gont wrote:

> Please note that Cisco Pix (and probably others) clear the URG bit by
> default.... so be prepared for the urgent indications to be unreliable...

Hola Fernando

 	I poked around a bit and shook some trees.  It seems as of PIX OS 
7.0 as well as the ASA 7.0, Cisco allows the URG bit to be controlled so 
it is not cleared - of course as you point out the default is to clear it. 
So perhaps consigning to the dust bin completely may not be as urgent to 
do yet. ;-)

wfms