>> It's not explicitly spelled out in XEP-0045 one way or the other, but >> I can't think of a reason it should happen (since the spec says "If a >> MUC service receives such extended presence information from an >> occupant, it MUST NOT reflect it to other occupants.") >> >> My personal preference is to spell out explicitly that this SHOULD >> NOT occur (I'm also ok w/ MUST NOT :) ), as I can't see a valid >> reason for having multiple, and a client-side assurance that there >> won't be multiple simplifies code.
> I'm in favor of MUST NOT. I'm probably a little late to the game here, but why does the spec say a MUC service MUST NOT forward extended presence information to other occupants? From personal experience, it is a useful business case, for example when an application is built on top of MUC and its users have extended identity information that they want to share with the other application users in the room. Of course, this could also be implemented by users sending broadcast messages to the room with the custom extension included, but the presence method has a 2-fold advantage: 1. Meaning. Information relating to identity just makes a lot more sense when it is in a presence message. 2. Caching. I believe MUCs cache the most recent presence from their members, so now when a new person joins and receives the presence information of everyone else in the room, they are already caught up with the custom extension data as well, versus the clients having to send a new empty message with the custom extension out to the room. Our application uses this functionality for users to share their identity information with the room, so I might be a little biased here :) But, I do want to show that there is a legitimate case for using this, so a MUST NOT seems a little strong...a SHOULD NOT seems better. Then again, 2 of the 3 XMPP server implementations we have tested with allow this behavior to occur. I'm curious, what's the reasoning behind a MUST NOT here? Cheers, Karthik Karthik Kailash | Product SocialVision, Online Television Becomes a Social Experience CELL • 408.768.7704 | WEB • www.socialvisioninc.com | FACEBOOK • facebook.com/socialvision | TWITTER • twitter.com/socialvision
