Hi Scott,
Speaking only for myself, I would like to address a couple of the
points that you have made.
It is my opinion that there is a difference between a working group
deciding to adopt a technology and a working group deciding
to delete a technology from an existing IETF specification. It is my
opinion that the second case should require a stronger demonstration
of consensus to change since the decision effects existing implementations,
documentation, text books etc.
First, I disagree with your basic premise. We don't make any
distinction between these cases, but if we did, all other things
being equal, I think it should be harder to add a new feature to a
specification than to take one out. Removing a feature from a
specification doesn't even prevent people from using it, whereas
adding a feature requires people to implement new code to be compliant
with the specification.
But, regardless of our differing opinions on this theoretical point, I
am not sure how it applies to this situation. Although a prefix for
site-local addressing was set aside in the IPv6 Address Architecture
(a PS RFC), the entire specification for the concept of site-local
addressing, including how you would actually use these addresses, was
only ever documented in the IPv6 Scoped Addressing Architecture I-D. At
the time that this decision was made by the WG, the latest version of
that I-D had expired. Various versions of the I-D had been considered
by the WG for years, but we had never reached rough consensus to send
this I-D to the IESG for publication.
The claim was made on the list that there was not consensus
to keep site local addresses, I think that is the wrong question
to ask - the proposal was to change a specification after its
publication there should have been a rough consensus to remove the
feature.
I'm not sure where this is coming from. You quoted the consensus
finding later in your message:
The chairs have read all of the messages on the list, and
based on your considerable input, we have determined that
the IPv6 WG does have rough consensus to deprecate the usage
of IPv6 site-local unicast addressing AND to investigate
alternative mechanisms for local addressing and local access
control.
In other words, we found that there was consensus to deprecate AND
replace site-locals, not that there was a lack of consensus to keep
them.
In response to your appended letter:
humm - it is not all that often that we have said that 2/3 is rough
consensus in the IETF - in my exterience if 1/3 is not in support
then I would not claim consensus (even 6 grit) - 3/4 would be very
rough indeed, 5/6 would be the mininum I would say was "rough
consensus"
The actual ratio of YES to NO responses to this poll was closer
to 3/4.
Also, the poll was not the only tool that the WG chairs (I was
one of them at the time) used to determine the consensus of the
WG. There was considerable discussion regarding this issue -- in
the WG meeting and on the list. This included a fairly large number
of people who gave conditional replies on the list, or who clarified
their meeting postion on the list along the lines of: (1) I do not
think we should deprecate site-local unless/until we replace them,
or (2) Although I think that we should deprecate site-locals, I also
think that we need a replacement. The chairs consensus call was
based on lengthy and careful consideration of all of the information
contributed by the WG, not just on the results of the opinion poll.
It is still my personal opinion that we correctly judged the
consensus of the WG regarding this matter.
Margaret