Re: [xmpp] draft-cridland-xmpp-session-00

Curtis King <> Tue, 10 June 2014 03:44 UTC

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From: Curtis King <>
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Date: Mon, 9 Jun 2014 20:44:27 -0700
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To: Dave Cridland <>
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Subject: Re: [xmpp] draft-cridland-xmpp-session-00
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On Jun 9, 2014, at 9:54 AM, Dave Cridland <> wrote:

> On 9 June 2014 17:36, Curtis King <> wrote:
> Instead of adding an redundant flag into the XMPP spec. Why doesn’t this draft state the <optional/> flag explicit and give the session as an example? Otherwise we will be adding <optional/> to more features than session.
> We've discussed, and rejected, this before, for example:
> I'm not averse to reopening the discussion, though I'll still argue against it. One or other of a generic <optional/> and <required/> will always be redundant, and multiple <required/> elements will often conflict.
> In any case, you'll note that <optional/> in this instance doesn't really mean "optional" so much as "redundant" - in fact, I think the name is an artifact of the discussion we had back then, though I can't find the thread that proposes it in this case. (But both M-Link and Prosody do this, so I assume it was discussed sometime).

It was in the 3921bis draft then removed. BTW, we are about to remove it from M-Link because it isn’t covered in any RFC or XEP.

This draft will require servers and client changes, you could accomplish the same goal by a pure informational draft pointing such features are optional. Then only certain clients need to change. Note: Good clients like Swift already ignore the session feature.

If you think it is clearer using a flag lets use a descriptive flag name like, rfc3921-compatibility.