Re: [v6ops] [Iot-directorate] Iotdir last call review of draft-ietf-v6ops-nd-cache-init-05

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 18 September 2020 19:44 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Jen Linkova <furry13@gmail.com>, "v6ops@ietf.org" <v6ops@ietf.org>, "iesg@ietf.org" <iesg@ietf.org>, "last-call@ietf.org" <last-call@ietf.org>
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Comments: In-reply-to "Pascal Thubert \(pthubert\)" <pthubert=40cisco.com@dmarc.ietf.org> message dated "Wed, 16 Sep 2020 10:13:07 -0000."
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Subject: Re: [v6ops] [Iot-directorate] Iotdir last call review of draft-ietf-v6ops-nd-cache-init-05
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Two other thoughts upon re-reading.

>   o  Some wireless devices are known to fiddle with ND packets and
>      perform various non-obvious forms of ND proxy actions.  In some
>      cases RSes might not even reach the routers.

this concern seems like an own-goal to me.[1]
  Help! DOCTOR, I enabled this fiddly thing, and now my network only gets
  three stars!

about 3.5, listening to all solicited node multicast address groups.
In the WiFi case, those multicast groups are preferrably emulated by APs
turning the multicasts into unicasts at higher Tx-rates.  So the system is
really listening to all of those groups already.   Maybe some vendors have
managed to put that into silicon, but I'll bet most have not.

I would assume that Joel Halpern, having written that other document, has
some knowledge about:
     Some routing vendors support such optimization already.

maybe those vendors could comment on how well it works, and what the CPU
impact is?

[1] https://en.wikipedia.org/wiki/Own_goal


-- 
Michael Richardson <mcr+IETF@sandelman.ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-