[Standards] UPDATED: XEP-0220 (Server Dialback)
dave at cridland.net
Tue May 17 18:04:49 UTC 2011
On Tue May 17 18:55:22 2011, Peter Saint-Andre wrote:
> On 5/17/11 11:51 AM, Dave Cridland wrote:
> > Versioning is *nearly* always the wrong thing to do.
In the message you quote, I continued:
Our namespace versioning is not versioning of the protocol in this
sense, because that would imply that "urn:xmpp:features:dialback:0"
is a subset of "urn:xmpp:features:dialback:1", whereas no such
assertion exists - the two are entirely unrelated from a protocol
standpoint, and any similarity is merely in the familial sense -
they're likely to have both been specified in the same document at
But - crucially - no compatibility is asserted; indeed the precisely
opposite assertion is made: the two protocols are mutually
This matches what I originally proposed in the message of mine you
have cited above:
That last portion we'll treat as a version number. Any time we cause
incompatibility between versions of the XEP, we update it. (Note,
that's not "every new XEP").
Note use of the word "incompatibility". The use of the term "version"
is, I agree, confusing, but my point here is that by changing the
namespace version number, we're actually both signalling, and
causing, an incompatible variant of the protocol.
I don't think the variants of dialback in discussion here are
incompatible within the subset currently defined.
Dave Cridland - mailto:dave at cridland.net - xmpp:dwd at dave.cridland.net
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