Re: [core] Using CoAP for P2P

Abhijan Bhattacharyya <abhijan.bhattacharyya@gmail.com> Tue, 07 April 2020 13:17 UTC

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From: Abhijan Bhattacharyya <abhijan.bhattacharyya@gmail.com>
Date: Tue, 7 Apr 2020 18:46:58 +0530
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To: John Carter <john.carter@taitradio.com>
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Subject: Re: [core] Using CoAP for P2P
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Yes, these are typical implementation considerations.
Particularly if we consider the case in point number 2, any control system
design must keep the stability of the system in mind. However, there will
be many cases where the exchanges are not necessarily synchronous. A
strictly synchronous model could probably be implemented with a typical
client server relationship using POST request and response payload
intelligently. P2P should be agnostic of any possible relationship between
the resources.

Thanks.

On Tue, Apr 7, 2020 at 2:18 AM John Carter <john.carter@taitradio.com>
wrote:

> 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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-- 
Regards,
Abhijan Bhattacharyya,
*Technologist by profession [IoT| Internet Protocols| 5G]*