[Standards-JIG] Server disco features: presence, iq, message

Dave Cridland dave at cridland.net
Mon May 8 08:00:53 UTC 2006


On Sun May  7 22:29:59 2006, Maciek Niedzielski wrote:
> Recently I noticed that my server returns in its disco#info query:
> 
> <feature var="presence" />
> <feature var="message" />
> <feature var="iq" />
> 
> What do these features really mean? I can guess, but why are they 
> used? I can understand advertising "presence-invisible", but 
> "presence"?

Yes, I've been implementing Disco in my client library, and I'm a 
little bewildered about what, exactly, the features mean from that 
standpoint, too.

In most cases, I know what the feature *is* - the registrar pointers 
are enough to tell me that - but I'm so sure what the advertisment is 
*for*, or to put it another way, what advertising it - or the lack of 
an advertisement - actually means in terms of protocol.

I'm particularly interested because while my client library (and thus 
Infotrope Polymer as a whole) could advertise support for a huge 
range of features (as can, presumably, any half-complete XMPP 
client), Infotrope Polymer as a whole is specifically designed to 
operate under low-bandwidth, so it makes some sense to only advertise 
those features that have a direct operational impact, rather than 
advertising every feature I possibly can.

Dave.
-- 
           You see things; and you say "Why?"
   But I dream things that never were; and I say "Why not?"
    - George Bernard Shaw



More information about the Standards mailing list