Re: [Dots] Role reversal in RFC7252

<mohamed.boucadair@orange.com> Tue, 12 November 2019 06:40 UTC

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From: <mohamed.boucadair@orange.com>
To: Carsten Bormann <cabo@tzi.org>
CC: "dots@ietf.org" <dots@ietf.org>
Thread-Topic: Role reversal in RFC7252
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Date: Tue, 12 Nov 2019 06:40:22 +0000
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Subject: Re: [Dots] Role reversal in RFC7252
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Hi Carsten, 

Fully agree if we model an endpoint as both a client and server.

The concern I had is when we want to model an endpoint solely as an "client" (or as a server).

Thanks. 

Cheers,
Med

> -----Message d'origine-----
> De : Carsten Bormann [mailto:cabo@tzi.org]
> Envoyé : vendredi 8 novembre 2019 18:10
> À : BOUCADAIR Mohamed TGI/OLN
> Cc : dots@ietf.org
> Objet : Re: Role reversal in RFC7252
> 
> On Nov 8, 2019, at 13:29, <mohamed.boucadair@orange.com>;
> <mohamed.boucadair@orange.com>; wrote:
> >
> > Hi Carsten,
> >
> > Can you please help indicate whether (and thus which part of) RFC7252
> discusses client/server role reversal so that a CoAP server can send (non-
> Empty) requests to a CoAP client?
> 
> 
> 2.  Constrained Application Protocol
> 
>    The interaction model of CoAP is similar to the client/server model
>    of HTTP.  However, machine-to-machine interactions typically result
>    in a CoAP implementation acting in both client and server roles.
> 
> Obviously, the one sending a request is always a client. But it might have
> been a server in the last  interaction.  Because we don’t need a connection
> (or, with RFC 8323, the connection does not dictate the direction), this is
> easy to do.
> 
> Grüße, Carsten