Re: [core] coap discovery

Michael Richardson <mcr+ietf@sandelman.ca> Wed, 18 August 2021 11:06 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Christian =?us-ascii?Q?=3D=3Fiso-8859-1=3FQ=3FAms=3DFCss=3F=3D?= <christian@amsuess.com>, Peter van der Stok <stokcons@bbhmail.nl>, core@ietf.org
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Subject: Re: [core] coap discovery
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> Ok, then I misunderstood; next attempt. Would it look roughly like this,
> then?

+-----------+-------------+---------+----------------------+
| IP header | UDP header  | CBORUDP | DTLS containing CoAP |
+-----------+-------------+---------+----------------------+


Yes, that's essentially it.
Although the "DTLS containing CoAP" is actually embedded in the CBOR.
But then, each of the things are embedded in the thing to the left.

>In that case, I'd advertise it either as
>
>    <cborudp://[ip]:port>;rt=cborudp

Aside from the name, I hate having to make up a new scheme.

> For me, either would work; announcing a <coaps://[ip]:port/j> would IMO
> be misleading if no requests really arrive there through CoAP on DTLS
> directly on UDP.

Agreed.


--
Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide