North American Network Operators Group
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Re: ECN

  • From: Hank Nussbacher
  • Date: Sat Nov 08 11:31:51 2008
On Fri, 7 Nov 2008, [email protected] wrote:

On Fri, 07 Nov 2008 08:27:58 +0100, Mikael Abrahamsson said: 
for ECN to actually be useful, we (the ISPs) have to turn this option on
in the routers as well. Is anyone doing this today? What vendors support
it?


The only thing that's *required* for it to help is that the routers and
firewalls not actually *molest* the bits in the TCP SYN packet.  If you pass
them and *do nothing else*, it at least has the potential of being useful at
some other router along the path.  And let's face it - if *your* router is
congested enough for ECN to matter, there's a fairly good chance that the
router one hop up/downstream is *also* seeing some effects. Even if *you* don't
do anything else, your neighbor might - helping you out in the bargain.


See:
http://www.icir.org/floyd/ecn.html
http://www.cisco.com/en/US/docs/ios/12_2t/12_2t8/feature/guide/ftwrdecn.html

-Hank


  • References:
    • ECN Mikael Abrahamsson
    • Re: ECN Valdis . Kletnieks