Re: [DNA] Alternatives to "just send RS" when DNA starts

[JinHyeock Choi <jinchoe@gmail.com>]

Dear Greg

> Such an optimization may work, but its effectiveness is dependent
> on topology (single cell links would experience longer delays),
> and the amount of time available to upper-layer applications (for
> example, voip).
>
> It makes sense to mention this idea as an optimization to reduce
> the effect of multicasts on the link-layer.  I'd suggest inclusion
> of a tentative link-layer address option, as the source
> address of the NS is likely to be considered optimistic for DAD
> purposes (it may not help, but may avoid the reverse NS/NA exchange
> if the router doesn't have the host in the NCE).
>
> How about:
>
> "...
> Multicast transmission has been shown to increase bandwidth
> consumption on certain wireless media at a rate much greater
> than that caused by unicast transmission.   On such media,
> it MAY be useful to send a unicast NS transmission
> to the global address of one of the configured routers upon
> reception of a link-layer hint.  This would avoid transmission
> of a multicast Router Solicitation if the router was available.
> The RS could then be delayed for an interval corresponding to
> the duration required to receive the unicast NA, if the router
> is still reachable.
>
> This optimization is dependent on topology, and increases delay
> and packet transmission if the link is composed of a single cell.
> Additionally, hosts with applications that are not able to delay
> for the lost NA in case of link-change SHOULD use RS instead.
> ..."

The above changes the existing DNA solution procedure, so I think we'd
better investigate it from the various angles. I am concerned about
relying on RTT value which may be volatile in wireless environment.

Thanks for your kind consideration.

Best Regards

JinHyeock