IETF RFC on "the implementation of the TCP urgent mechanism"

From: Fernando Gont <>
Subject: IETF RFC on "the implementation of the TCP urgent mechanism"


RFC 6093, entitled "On the Implementation of the TCP Urgent Mechanism"
has just been published. It is available at:

This RFC has been motivated, to a large extent, by the behavior of
some well-known firewalls.

The Abstract of the RFC is:

---- cut here ----
   This document analyzes how current TCP implementations process TCP
   urgent indications and how the behavior of some widely deployed
   middleboxes affects how end systems process urgent indications.  This
   document updates the relevant specifications such that they
   accommodate current practice in processing TCP urgent indications,
   raises awareness about the reliability of TCP urgent indications in
   the Internet, and recommends against the use of urgent indications
   (but provides advice to applications that do).
---- cut here ----

More informantion about this and other related issues is available at
my web site:


Best regards,
Fernando Gont
e-mail: ||
PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1

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