Re: [Dots] Role reversal in RFC7252

Carsten Bormann <cabo@tzi.org> Fri, 08 November 2019 17:10 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Fri, 8 Nov 2019 18:10:05 +0100
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Subject: Re: [Dots] Role reversal in RFC7252
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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