Hi all, indeed scoping is a pain... specifically since it is not carried as
a part of the address.
In any case we should give an escape path out of this ambiguity to a "known"
world. 
Meaning if a node is configured with a global addresses the global addresses
will have higher priority being used as a source address over SL.
Since the IPv6 transformation is expected to be evolution(vs. revolution) I
believe the vast majority of the networks will choose to take this path.
I know there is a draft in the work for this, and I believe this is what it
says (correct me if I am wrong...).
This way the vast majority of users knows there is a way to get over this
problem... 
This is also solves the scoping problems for LL and multihome hosts.  

Shuki
-----Original Message-----
From: Dan Lanciani [mailto:ipng-incoming@;danlan.com]
Sent: Monday, October 28, 2002 3:52 PM
To: [EMAIL PROTECTED]
Subject: RE: Limiting the Use of Site-Local


I think it's great the folks are starting to consider the difficult problems
associated with site-local addresses in particular and scoped addresses in
general.  In the past these have been glossed over with hand-waving
arguments
that scopes would ``just work'' with minimal application involvement and a
little DNS magic.

Before you try to solve the problems by effectively reducing scopes to a
degenerate case of one and restricting site-local addresses to sites with
no global addresses (or even with no external connectivity), please keep in
mind that site-local addresses have been offered up as the solution to a
number of other problems which themselves were difficult to hand-wave away.
For example, the ability to have long-term tcp connections within a site in
the face of global address renumbering has--given the lack of any protocol
or application support for that renumbering--been pushed onto site-local
addressing.  (The problem is hardly confined to tcp, but that's the usual
example cited.)

Any language that reduces site-local addresses to second-class citizens (or,
worse, implies that they should not be used concurrent with global
addresses)
will give stack and application vendors an excuse to fail to support such
configurations.  I don't think you want to open such a huge can of worms as
it will entail revisiting every problem that has been ``resolved'' with an
admonition to simply use site-local addresses.

                                Dan Lanciani
                                ddl@danlan.*com
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