At 12:52 PM 12/2/2002 +0100, Kurt Erik Lindqvist wrote:
My memory of the discussions accords with the summary given by Keith
above. In addition, the general tenor of the discussion indicated to me
that the two issues were linked: that consensus on limiting site-locals
was contingent upon initiation of an effort to design a workable scheme
for privately-routable PIs, with the global routing of PIs left for
subsequent discussion.
So the remaining question besides the PI issue would be to define "limit"
then?
I had proposed limiting the use of site-locals to completely isolated
networks (i.e. test networks and/or networks that will never be
connected to other networks). This would give administrators of
those networks an address space to use (FECO::/10) for those networks
that wouldn't conflict with anyone else's and could be filtered by ISPs,
etc. (in case anyone ever makes a mistake and connects an "isolated"
network to the Internet). This is actually what site-local addresses
(and RFC 1918 addresses) were originally invented for...
If we limit site-locals to this case, they can be treated _exactly_ like
globals in all implementations (since they will be global to any network
where they should be used), and all BGP routers could ship with a default
filter to block propagation of these routes (which the administrator
would have modify in the unlikely event that he wanted to use BGP in
his completely isolated network).
I'm working on a draft that explains why I believe that site-locals
need to be limited to this extreme, and that draft will provider further
details of the proposal. I'm actually NOT proposing any automatic
mechanism to enforce this restriction, as I just think that makes
implementations larger and more cluttered.
This was the "limited usage" model discussed at the Atlanta meeting.
There was also a "moderate usage" proposal put forth by Bob Hinden in
the meeting, which would allow the use of site-local, but would not
allow sites to border each other (site-local addresses would be
filtered in firewalls). The details of this model haven't been
documented in detail, but it has the advantage that it would allow
the use of site-locals on intermittently connected networks (ones that
may not always have global addresses available from their ISP, or where
their ISP-provided addresses may change on each connection).
The WG had consensus to limit the use of site-locals to one of these
two proposals, but we were pretty much split down the middle between
them. One of the issues, I think, is that neither one was well-enough
documented for people to understand the details. So, I'm working on
documentation for the "limited usage" proposal.
Bob, are you or anyone else working to document the "moderate usage"
proposal?
Margaret
--------------------------------------------------------------------
IETF IPng Working Group Mailing List
IPng Home Page: http://playground.sun.com/ipng
FTP archive: ftp://playground.sun.com/pub/ipng
Direct all administrative requests to [EMAIL PROTECTED]
--------------------------------------------------------------------
