Subject: RE: Optimistic DAD draft ...

From: "Hesham Soliman (EAB)" <[email-masked]>
Date: Thu, 17 Oct 2002 11:23:25 +0200

> To clarify: we've been doing some work to identify and isolate
  > the causes of L3 handover delays, and they each seem solvable
  > by one means or another.
  > 
  > For example, hmipv6 offers one possible way of eliminating the RTT
  > delay caused by sending BUs. In its current form, it probably
  > isn't scalable to that level, 

=> Why not? I think it is scalable to that level simply
because you can plug more anchor points as you see 
fit. it's as scalable as HAs are in MIPv6.

  > 
  > Actually, JinHyeock reminded me that I'd forgotten to mention
  > the Movement Detection Delay ... we've been tackling that
  > with inter-layer signalling to prompt router solicitations.

=> What you're doing (optimistic DAD) can be combined 
with Fast Handovers to completely eliminate movement 
detection delay.

  > The Optimistic DAD thing comes about because I thought
  > the FH stuff was getting a bit theoretical and I felt that a
  > set of small, easily implemented patches, one per cause of
  > L3 handover delay, would be a good way to move forward in the
  > short term.

=> My very initial effort (with Karim) with Fast handovers was aimed 
at: anticipation + optimistic DAD + HMIPv6.
I still think this is the simplest solution and will achieve
excellent results. We already have some basic simulations 
(not to the level that Jim is asking for) that prove this and 
more to come.

Hesham

  > 
  > cheers,
  > -----Nick
  > --------------------------------------------------------------------
  > 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-masked]
  > --------------------------------------------------------------------
  > 
--------------------------------------------------------------------
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-masked]
--------------------------------------------------------------------

---

From: "Nick 'Sharkey' Moore" <[email-masked]>
Date: Fri, 18 Oct 2002 12:07:14 +1000

> fit. it's as scalable as HAs are in MIPv6.

My main concern would be issues to do with the MAP information
propagation, and the MAP selection algorithm ... I think there's
some common ground between the tactics of HMIP and the FMIP
three-party-handover and I suspect the best solution is in that
region somewhere ... 

> detection delay. [...]

It's tricky getting anticipation signalling out of most 802.11
drivers, but we've had success getting L2 to signal L3 that it has
just reassociated, causing L3 to RS. Greg Daley has more information
here, I'm sure he'll chip in when he gets back to town ...

-----N