Subject: Re: [DNA] Landmark vs Link-ID prefix solution

From: JinHyeock Choi <[email-masked]>
Date: Mon, 01 Aug 2005 16:24:00 +0900

Dear Jim

Thanks for your detailed feedback. 

> I have tried to pereceive implementation pain and advantage from both
> Landmark and Link-ID views, and the complexity of the code and
> extensions required.  I think this gets into the time vs. space issues
> we faced looking at OSI ES-IS vs ARP when defining ND years ago, only a
> much harder technical problem (I think its up there with SHIM6 work).  I
> see similar positions and debates.  Most of the mail for me has not been
> helpful to sway me one way or the other yet.  It has shown me neither is
> complete yet. What I like about Landmark it is a pure extension to ND
> for IPv6, but what I don't like nor can support at least right now is
> modifying the current RA.  Doing that is not good and I would at least
> like to see means to enhance or form new RA for particpating Landmark
> hosts and routers.  What I like about the Link-ID is I believe it will
> converge quickly for one of my hot buttons for mobility and that is mesh
> networks (note not MANETs and I can get into the diff offline "only"
> with others, per Greg's mail to keep the focus here).  I intend to do in
> depth technical review of both and ask some folks I know out of the IETF
> building mobile networks now for products with MIPv6 who want to be
> anonymous to help me review it as ghost persons, and I am building some
> to of course, so I have a bias clearly. Possibly there is a compromise
> and integration of ideas here.

It would be very nice to have feedback from people building mobile networks. 
I guess mobile operators (and mobile equipment vendors) would be an important 
(maybe the most important) customers for DNA solution, so their opinions 
would be of much value.  

> I am assuming on both sides of the architectures is that there is no IPR
> from any company as authors on either of these solutions?  If there is
> and I missed it in the specs, and I will check again, please speak up
> now and tell us you have patents on what your proposing.  This has to
> stop in the IETF and will probably kill CGA and other ideas that may
> never get widely used in the market.  Most of us are quite sick of it
> and I consider it dishonorable if not presented up front immediately.

There is no IPR attached to LinkID. 

Thanks for your kind consideration. 

Best Regards

JinHyeock

---

From: Brett Pentland <[email-masked]>
Date: Mon, 01 Aug 2005 21:41:19 +1000

Hi Jim,

Thanks very much for your feedback.  I think that part of the difficulty
with the discussion on the list is that we are comparing solutions
that are really very similar (and in fact there are others that could
be made to work fairly well too).

For both of the proposals, the routers on a link need to monitor what
the other routers are doing, and for compatibility with non-DNA-enhanced
routers both proposals, rely on CPL which requires the hosts to monitor
all of the prefixes as well.  The differences are in which bits of the
information get exchanged.

Because the differences are not dramatic the discussion has focussed
on a search for corner cases where one does better than the other and
maybe this focus on minutae has muddied the waters more than clearing
them.

I've got a couple of questions for you below.

Thanks again for your review.
Brett.

PS.  I'm not aware of any IPR encumberences on any of these ideas.

Bound, Jim wrote:
> hosts and routers.

I'm not sure I understand the comment about modifying the current RA.
Are you referring to the addition of the Landmark Option, the suggestion
that PIOs, etc. need not be included if the answer to the landmark
question is "yes", or something else?

>  What I like about the Link-ID is I believe it will

Can you say what it is about mesh networks that Link-ID serves well?
Maybe it's something that we haven't fully considered and it would be
useful to know more about it.