Re: [core] coap discovery

Christian Amsüss <christian@amsuess.com> Tue, 17 August 2021 12:48 UTC

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Date: Tue, 17 Aug 2021 14:48:34 +0200
From: Christian =?iso-8859-1?Q?Ams=FCss?= <christian@amsuess.com>
To: Peter van der Stok <stokcons@bbhmail.nl>
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Subject: Re: [core] coap discovery
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Hi Peter,

> However, the join-proxy discovers the Registrar port by discovering a
> related coap resource and its port on the Registrar with rt = brski-yyy
> 
> Question:
> Is this a legitimate use of coap discovery to discover the non-standard
> ports on join proxy and Registrar?

If that protocol is really not CoAP, it can be legitimately discovered,
but should IMO be indicated with a different protocol than coap, say
<brski://registrar-ip:port/registrar-resource>;rt=brski-yyy

However, just to get a better understanding, why is the protocol through
which the CoAP messages are forwarded between the join-proxy and the
registrar neither CoAP nor a new CoAP transport? (Just sounds like it'd
be working around the very shortcomics of CoAP proxies that RFC8974
resolved). Is this protocol described anywhere so far?

BR
c

-- 
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