[Standards] SIFT

Joe Hildebrand hildjj at gmail.com
Mon May 18 18:20:58 UTC 2009

2009/5/18 Jiří Zárevúcky <zarevucky.jiri at gmail.com>:
> Well, until now I believed that "unavailable" presence doesn't mean
> "show me offline", but "make me unavailable for presence exchange and
> messaging". But you're right, it doesn't really matter.
> Anyway, if SIFT capable client went invisible mid-session, it could do
> so by sending unavailable presence. But possibly without any prior
> SIFT command. So I think it should be noted that either supporting
> client must use sift to initiate it's "SIFT based session" prior to
> using such invisibility, or the server must not terminate the
> communication availability even when there was no explicit SIFT.  If
> it is not specified, the first possibility should be implicit for the
> client developer to avoid problems, but I'm afraid not everyone would
> realize that.

Agree.  The default is not to sift, and we may not have captured that
adequately in the draft yet.  We also need to make it explicit that
you can change your sift rules at any time.

There is still a use case for priority -1 presence; I'm a presence
publisher that doesn't want to receive messages.  The -1 here is a
hint to the sender that they shouldn't expect me to get this message
if they send it right now.  We probably need to add text like this:

If a client requests message sifting, but sends presence, it SHOULD
send priority -1 as a hint to subscribers.

Joe Hildebrand

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