Re: WG Review: Mobility for IPv6 (mip6)

[Thomas Narten <narten@us.ibm.com>]

Hi Vijay.

> > 2) Features such as renumbering of the home link, home agent discovery,
> >       Route Optimization, which are currently a part of the base
> >       specification can be specified more explicitly as separate
> >       specifications. This will also enable modularizing the Mobile
> >       IPv6 specification further into the minimal subset and add-on
> >       features. Some of these specifications will be identified as
> >       base mechanisims of Mobile IPv6.

> I dont see how the above paragraph has anything to do with the
> primary goal of the WG.

I (and others) will argue that one of the reasons it took so long to
get the current spec finished is that it got too large, and that it
had too many unrelated things crammed in it.  Large documents are hard
to get through the process because there is so much more that everyone
has to agree to.

The exact same thing will happen with any revised document. The
problem will quite possibly be even worse, because there will be stuff
that everyone agrees needs to get fixed, but there will be
controversial (and unrelated) stuff that folks can't agree on, and as
a result the document won't actually get revised in a timely
fashion. And then, as time goes on, getting more changes gets even
harder because more and more implementations have learned how to deal
with the existing (possibly broken) spec and don't want to change
their implementations and don't want a revised spec to make their
implementations valid, and so forth.

So, I think it is actually quite important that the base spec be split
apart, and that this is an important step in getting revised documents
out in a reasonable time period.

Even the current history of the spec shows the problems of bundling
too much stuff into it. The basics for MIPv6 were understood and
"done" a long time ago. But RO proved to be a big problem.
Unfortunately, RO was part of the base spec and it was not possible to
publish just the base MIPv6 two years ago (and I'll note that MIPv4
doesn't have RO, and is being deployed, so publishing that would have
been useful). 

Thomas