Re: [core] Using CoAP for P2P

John Carter <john.carter@taitradio.com> Mon, 06 April 2020 20:48 UTC

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From: John Carter <john.carter@taitradio.com>
Date: Tue, 7 Apr 2020 08:48:18 +1200
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To: Abhijan Bhattacharyya <abhijan.bhattacharyya@gmail.com>
Cc: core <core@ietf.org>
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Subject: Re: [core] Using CoAP for P2P
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While the standard is, unlike the http standard, agnostic as to who is the
client and who is the server and the roles can switch.... in practical
experience I'd advise caution.

1. If you are not careful you end up with a system that only works if and
only if all nodes are up and working. The best thing about REST is it
reduces coupling and dependencies between client and server. If you two way
couple them, you have made the coupling a lot stronger.

2. If you are not careful, you can end up with update loops. ie. Node A
updates an observable resource, in response to which Node B updates a
derived observable resource, which Node.... updates a derived observable
resource, which triggers an update on Node A and around we go.


On Thu, Apr 2, 2020 at 12:31 AM Abhijan Bhattacharyya <
abhijan.bhattacharyya@gmail.com> wrote:

> Hi,
> Is there any standardized mechanism to use CoAP for a P2P connection?
> Thanks.
>
> --
> Regards,
> Abhijan Bhattacharyya,
> *Technologist by profession [IoT| Internet Protocols| 5G]*
> _______________________________________________
> core mailing list
> core@ietf.org
> https://www.ietf.org/mailman/listinfo/core
>


-- 
John Carter
Phone : (64)(3) 358 6639
Tait Electronics
PO Box 1645 Christchurch
New Zealand

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