Re: [core] [Cbor] Interface names (Re: changes in draft-ietf-cbor-network-addresses-05.txt)

Christian Amsüss <christian@amsuess.com> Tue, 27 July 2021 09:55 UTC

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Date: Tue, 27 Jul 2021 11:55:05 +0200
From: Christian =?iso-8859-1?Q?Ams=FCss?= <christian@amsuess.com>
To: Carsten Bormann <cabo@tzi.org>
Cc: Erik Kline <ek.ietf@gmail.com>, cbor@ietf.org, 6MAN <6man@ietf.org>, core@ietf.org
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Subject: Re: [core] [Cbor] Interface names (Re: changes in draft-ietf-cbor-network-addresses-05.txt)
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Hello Carsten, groups,

> Interface names are local, so it doesn’t make a lot of sense to carry
> them around between systems, which is where CBOR is mostly used these
> days.

two applications come to mind:

* RD introspection[1] uses zone identifiers in what may be described as
  debug output: Usually an RD won't show you a resource on a fe80::
  address not on your link, but as an administrator you may need the
  birds-eye view.

* Many network devices offer a remote way to run a ping; when the
  process is started via CBOR, it'd be useful to give an interface
  identifier.

I'm not particularly advocating that we add zone identifiers to the new
tags (as I can use URIs or even work around completely in the former,
and don't have a pressing need for the latter) -- but with those
examples, a statement like "we don't specify interface identifiers
because they shouldn't be serialized anyway" would be overreaching.

BR
c

[1]: https://www.ietf.org/archive/id/draft-amsuess-core-resource-directory-extensions-05.html#name-zone-identifier-introspecti

-- 
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