Re: Why ULA: low collision chance (Was: IPv6 fc00::/7 — Unique local addresses)

[William Herrin <bill () herrin us>]

On Thu, Oct 21, 2010 at 6:27 PM, Joel Jaeggli <joelja () bogus com> wrote:
> On 10/21/10 6:02 AM, William Herrin wrote:
> > On Thu, Oct 21, 2010 at 8:14 AM, Ray Soucy <rps () maine edu> wrote:
> > > That's assuming ULA would be the primary addressing scheme used.  If
> > > that became the norm, I agree, the extra uniqueness would be
> > > desirable, perhaps to the point that you should be asking an authority
> > > for FC00::/8 space to be assigned.  But then why wouldn't you just ask
> > > for a GUA at that point.
> >
> > Because you might want space that doesn't route on the Internet so
> > that if your routes accidentally leak external folks still can't reach
> > you?
>
> Announce your gua and then blackhole it and monitor your prefix. you can
> tell if you're leaking. it's generally pretty hard to tell if you're
> leaking rfc 1918 since your advertisement may well work depending on the
> filters of your peers but not very far.

Joel,

I have a condensate overflow pan under my computer room air
conditioner that collects water if it leaks. I also have an alarm that
alerts me if there's a leak and careful maintenance to prevent it from
leaking in the first place. But I still have the pan. Even though a
leak could fill the pan and overflow, I insist on having a pan there
to try to catch the water.

How many guesses do you need to figure out why?

Regards,
Bill Herrin


-- 
William D. Herrin ................ herrin () dirtside com  bill () herrin us
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