Re: [netmod] backward compatibility requirements in draft-verdt-netmod-yang-versioning-reqs-00

Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Sat, 21 July 2018 05:49 UTC

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Date: Sat, 21 Jul 2018 07:49:35 +0200
From: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
To: Andy Bierman <andy@yumaworks.com>
Cc: NetMod WG <netmod@ietf.org>
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Subject: Re: [netmod] backward compatibility requirements in draft-verdt-netmod-yang-versioning-reqs-00
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On Fri, Jul 20, 2018 at 02:41:33PM -0700, Andy Bierman wrote:
> Hi,
> 
> I strongly object to requirement 3.1:
> 
> 
>     3.1  The solution MUST provide a mechanism to allow servers to
>             support existing clients in a backward compatible way.
> 
> 
> 
> This is not what servers do today at all.
> They provide only one version of an implemented module, as specified in RFC
> 7950.

But today a backwards incompatible change leads to a new module and
you can very well implement two modules if that is reasonable to do in
order to allow clients a transition period.

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: +49 421 200 3587         Campus Ring 1 | 28759 Bremen | Germany
Fax:   +49 421 200 3103         <https://www.jacobs-university.de/>