Re: [core] Erik Kline's No Objection on draft-ietf-core-resource-directory-26: (with COMMENT)

"Christian M. Amsüss" <christian@amsuess.com> Thu, 25 February 2021 12:47 UTC

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Date: Thu, 25 Feb 2021 13:47:11 +0100
From: Christian =?iso-8859-1?B?TS4gQW1z/HNz?= <christian@amsuess.com>
To: Erik Kline <ek.ietf@gmail.com>
Cc: The IESG <iesg@ietf.org>, draft-ietf-core-resource-directory@ietf.org, core-chairs@ietf.org, core@ietf.org, jaime@iki.fi, jaime.jimenez@ericsson.com
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Subject: Re: [core] Erik Kline's No Objection on draft-ietf-core-resource-directory-26: (with COMMENT)
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Hello Erik,

> In the case (perhaps not the common case) there the RDAO IPv6 address is the
> same as the source address of the RA itself, the length field could be just 1
> and the IPv6 address field omitted.
> 
> [...]
>
> I'll leave it up to the group to consider whether this is a useful optimisation
> or not.  Perhaps this idea has already been considered and rejected, though.

it hasn't been considered before, but I think that the case is rare
enough to cause more trouble than be worth it (for it's a corner case
that'd receive little testing). One reason for this is that RDs will
prefer to announce global addresses to get reachable base addresses (cf.
Section 4.1, where we give guidance for multicast cases to pick global
addresses).

Thank you
Christian