[Bug 45145] New: attempt to call offline/invisible people by guessing a fairly interoperable dialect

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=45145

             Bug #: 45145
           Summary: attempt to call offline/invisible people by guessing a
                    fairly interoperable dialect
    Classification: Unclassified
           Product: Telepathy
           Version: git master
          Platform: Other
        OS/Version: All
            Status: NEW
          Severity: enhancement
          Priority: medium
         Component: gabble
        AssignedTo: telepathy-bugs at lists.freedesktop.org
        ReportedBy: simon.mcvittie at collabora.co.uk
         QAContact: telepathy-bugs at lists.freedesktop.org


We currently try to call offline/invisible people via temporary presence
sharing (aka "decloaking" within Gabble;
<http://xmpp.org/extensions/xep-0276.html>) which basically sends them directed
presence with an embedded request to leak their presence back to us.

This is largely useless, because nobody implements the "leak your presence"
side except us, we have it off-by-default ourselves, and the reason it's
off-by-default is that it's a presence leak. In principle it could be useful
when calling gateways in which "leaking" presence is not a problem (because all
the virtual users are permanently available anyway), but telepathy-fargo is the
only gateway that actually implements it, and is not widely deployed. It's also
not a particularly elegant protocol (there's an extra round-trip when it works,
and an arbitrary delay when it doesn't).

Now that people implement modern versions of Jingle and the namespace has
stopped randomly changing, we could do a lot worse than just trying it:

19:47 < Robot101> google tends to assume an interoperable jingle subset for 
                  calls and just whack an offer together
...
19:55 < smcv> Robot101: oh, hmm. how does the "just staple together some caps" 
              work if you don't know a full-JID?
19:56 < smcv> that's the other reason we need presence, apart from knowing 
              which dialect/etc. to guess at
19:56 < smcv> maybe we could send it to apparently-offline people as a 
              <message/> and they get a "missed call" though :-)
19:56 < Robot101> basically if you peg in a JID (whether a bare server, 
                  user at server or full) then the other end can choose to respond 
                  and make it work
19:57 < Robot101> (be aware call forking may ensue, I guess?)
19:57 < smcv> oh I see. so the bare JID case (which is all you'll ever get 
              unless you type in or remember resources) will only work with 
              server cooperation
19:57 < Robot101> yeah
19:57 < Robot101> in this picture, a gateway is a co-operating server

-- 
Configure bugmail: https://bugs.freedesktop.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the QA Contact for the bug.
You are the assignee for the bug.