Re: [core] [dnssd] CoAP resource discovery and DNS-SD

Ted Lemon <mellon@fugue.com> Fri, 13 May 2022 23:23 UTC

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From: Ted Lemon <mellon@fugue.com>
Date: Fri, 13 May 2022 19:22:41 -0400
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To: Toerless Eckert <tte@cs.fau.de>
Cc: core@ietf.org, dnssd@ietf.org
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Subject: Re: [core] [dnssd] CoAP resource discovery and DNS-SD
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We were never able to figure that out either. The mapping from Core RD in
particular to DNS-SD is something that the DNS-SD working group actually
pursued for a while (Kerry Lynn worked on this pretty heavily for about a
year).

On Fri, May 13, 2022 at 7:20 PM Toerless Eckert <tte@cs.fau.de> wrote:

> Dear CoAP WG
>
> I am trying to figure out how to use CoAP discovery as specified in RFC7252
> (and expanded in rfc6690 and rfc7390),  but i can not figure out how
> one would encode basic parameters of a resource, such as those supported
> in DNS-SD, rfc6763:
>
> When discovering more than one instance of a resource, such as possible,
> when using multicast discovery as on rfc7252, clients will have to figure
> out,
> which instance of a resource to select. DNS-SSD has priority and weight
> parameters associated with each instance. How would one describe/encode
> such instance and weight ?
>
> When discovering one or more instance via DNS-SD, the discoering client
> may further select the best instance in terms of interoperability,
> functionality
> and performance based on one or more key=value property pairs describing
> the instance. How is this done in CoAP ?
>
> Thanks a lot!
>
> Toerless
>
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