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

Christian Hopps <chopps@chopps.org> Sun, 29 July 2018 05:07 UTC

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From: Christian Hopps <chopps@chopps.org>
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Date: Sun, 29 Jul 2018 01:07:17 -0400
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Cc: Christian Hopps <chopps@chopps.org>, Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>, NetMod WG <netmod@ietf.org>
To: Andy Bierman <andy@yumaworks.com>
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Subject: Re: [netmod] backward compatibility requirements in draft-verdt-netmod-yang-versioning-reqs-00
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One answer to a slightly more general version of this question (why is OK for the clients to do nothing while the servers do the work) is that the client developers are often the server developers customers, they pay the bills.

Also in general there is a one to many mapping from a server to it's clients, the overall cost of updating a server and of it supporting multiple versions or transforming or whatever is much less than the overall cost of all the users of that server updating their client software.

I'm not advocating for clients never updating, but I think it's unreasonable to think that clients will be updating as fast as servers, or to design a versioning scheme that assumes anything like that.

Thanks,
Chris.

> On Jul 24, 2018, at 11:11 AM, Andy Bierman <andy@yumaworks.com>; wrote:
> 
> Why is it OK for the client developer to decide "we are sticking with the
> defective version of the module and not going to upgrade to
> the fixed version like the server developers have done."
>