On Sep 13, 2007, at 3:16 AM, Jari Arkko wrote:
Roger,
On 9/12/07, ietf-discuss@xxxxxxx <ietf-discuss@xxxxxxx> wrote:
<snip>
http://sa.vix.com/~vixie/ula-global.txt has my thoughts on this,
which
i've appropriated without permission from hinden, huston, and narten
and inaccurately failed to remove their names from (since none of
them
supports the proposal). in fact, nobody in the ietf intelligensia
supports the proposal. the showstopped is that this appears to
many as
an end-run around PI, and the fear is that there's no way to
prevent it
.......
The question on the table (and also part of 6man charter)
is whether we need an additional type of ULAs, one that is
centrally allocated. Such addresses might be useful for a couple
of reasons. One reason is that we could guarantee uniqueness,
which might be important, e.g., for a company that is running
a lot of small company networks as a business, and wants to
ensure the address spaces do not collide. But another, more
important stated reason was that we should have a way give
people address space that is different from PI in the sense
that those addresses are not recommended to be placed
in the global routing table.
Arguments against such address space relate to the
following issues:
- The costs for any centrally allocated space are likely going to
be the same, so what is the incentive for the customers to
allocate ULA-C instead of PI?
- There is no routing economy that would push back on
advertising more than the necessary prefixes, so
what is the incentive that keeps the ULA-C out
of the global routing table as years go by? (When
the companies that allocated ULA-C grow, merge,
need to talk with other companies, etc.)
The end result of our discussions was that we clearly do not
have agreement on the way forward, and we settled for
writing a draft about the issues instead. That is still in the
works.
I'm just catching up with this thread today: If I summarize my
understanding from the above in one sentence: there seems a perceived
difference between PI and ULA-C prefixes, which, as far as I can see,
does not exist.
Whether a unique prefix is/not globally routable is determined by
whether it gets injected into the routing system, no matter how it is
labeled.
Lixia
_______________________________________________
Ietf@xxxxxxxx
https://www1.ietf.org/mailman/listinfo/ietf