Re: [DNA] High-level overview of DNA, take 2

[Greg Daley <gregd@research.panasonic.com>]

JinHyeock Choi wrote:
[cut]
>>
>> If you arrive back within a second, you would probably see the
>> NA O=1 to all nodes from the node which started DAD while you were
>> away.   Placing the addresses in Optimistic state makes sense here,
>> but it may not be necessary to send an NS (opinions welcome).
>>
>> If you've been away for an entire second, the host may arrive back
>> after DAD has completed on a peer node.  A full optimistic DAD would
>> be required.
> 
> It make sense to differentiate host's behavior according to the time
> of absence. The longer a host is absent, the more care it should take.
> BTW how a host can measure its time of detachment? Shall this require
> a precise link-down event notification?

I'd guess that link-down indications could be used to allow for
more selective behaviour, if there's knowledge of detachment time.


[cut]
>> This is why we've used multicast.   Perhaps there is a way for all
>> links to have the same (MAC) unicast destination for a serving router,
>> which would avoid the issue of the multicast RS leaking back onto a
>> wireless LAN.  There are other ways of dealing with this issue
>> today though (e.g. group filtering).
>>
>> Ideas like special destinations have been discussed previously off-list,
>> but have the issue that they require modification to routers.
>>
>> RS/RA has the advantage that it is always there, and if people
>> wish to improve its performance in scheduling or efficiency,
>> it is possible to upgrade it (or potentially the network it is on??).
> 
> Kindly be aware that we can avoid multicast in the air with FRD. :-)

Indeed.

Greg