Microsoft's participation in World IPv6 day

Mark Andrews marka at
Mon Jun 6 02:14:49 UTC 2011

In message <BANLkTiniAKw+GPPcmJFs8QFBdRM7QEk30w at>, Cameron Byrne 
> On Jun 5, 2011 6:15 PM, "Mark Andrews" <marka at> wrote:
> >
> >
> > In message <BANLkTimGkuL7ycrYG6kTC1U7OWis9dOA+YaV-YHwr+5C8=
> 0Pxw at>
> > , =?UTF-8?B?SsOpcsO0bWUgTmljb2xsZQ==?= writes:
> > > 2011/6/6 Mark Andrews <marka at>:
> > >
> > > > There is no reason that they can't do a similar thing to move
> > > > customers who are doing things that break with LSN out from behind
> > > > the LSN.
> > >
> > > Oh, you're right, they'll surelly do that. But not in time, and not for
> fre=
> > > e.
> >
> > Well here in Australia I would be calling the ACCC is a ISP tried
> > to charge extra for a address that is not behind a LSN.  As for in
> > time it should be in place before they turn on LSN.  If you can
> > adjust port 25 filters whenever a customer gets a new address you
> > can also ensure that they get address from the correct pool when
> > they connect to the network.  This really isn't rocket science.
> > It's updating the provisioning database from a web form and generating
> > new configs based on that database.  Yes there is some work required
> > to ensure that this gets done properly and there needs to be checks
> > that address pools are appropriately sized.
> >
> Can you cite an example of an isp doing this? My assumption is that people
> will get LSN by default for standard residential broad band and business
> class will get public ip's.

It's how you handle the exceptions.  Home users have port 25 off
by default but can still get it turned on.  Most home users don't
need a public IP address as they are not running stuff that requires
it however some do so planning to handle the exceptions as efficiently
as possible is a good thing to do.

I've got two applications that won't work behind a LSN.  A sip phone
and a 6in4 tunnel however I'm not typical.

Looking at 6to4 and auto tunnels they really are a small percentage
of customers that could be auto detected by the ISP and be put into
the exception pool prior to enabling LSN.  Most CPE routers today
don't enable 6to4 (they either don't support IPv6 let alone 6to4
or its not turned on by default).  As for directly connected machines
many of then still require 6to4 to be turned on by hand (XP, Mac

What's easier for the ISP, detecting the  customers that use protocol
41 today and automatically adding them to a exception pool or
fielding the support calls?


> Without any commitments to cite, plan for the worst and hope for the best.
> Cb
> > If I were doing it I would also have checkboxes for some of the
> > more common reasons and include IPv6 connectivity as one then have
> > a 6 month grace period once the ISP offers IPv6 connectivity before
> > removing that as a valid reason for needing a address that is not
> > behind the LSN.
> >
> > > LSN is beeing actively implemented in the core network of several
> > > ISPs, and most didn't yet consider it as optional. Nor are ready for
> > > v6 connectivity to residential customers, though.
> > >
> > > For users behind a forced NAT (no way to disable it on the CPE) or
> > > LSN, the only way out is still tunneling. Talking about bandwidth and
> > > infrastructure waste...
> > --
> > Mark Andrews, ISC
> > 1 Seymour St., Dundas Valley, NSW 2117, Australia
> > PHONE: +61 2 9871 4742                 INTERNET: marka at
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at

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