Programming Jabber

Browsing

The more pervasive Jabber becomes and the more it is used, the larger the world of entities grows. And therein lies the challenge. How can we identify, organize, and navigate these entities in any useful way? Within the relatively narrow world of IM, the entities that exist (the IM users) and the hierarchies and relationships that are formed between them (where the only hierarchies are in the form of user rosters) don’t really present much of a problem; as all the entities are users, there’s no classification problem, and there’s no hierarchical navigation problem. But within a system that regards users, applications, and services as equals (the unifying concept of a JID is an especially powerful device here), we need to have some way of searching, traversing, discovering, and querying these entities that is consistent regardless of what those entities are. Enter Jabber Browsing.

Browsing was introduced in Version 1.4 of the Jabber server to solve some specific problems with service discovery: how clients found out about what services (say, what IM transports) were available from the Jabber server that they were connected to. The namespace that supported the original discovery mechanism (jabber:iq:agents) was found to be too restrictive and, more importantly, too specific. A more generic way of describing entities in the Jabber world was needed.

Browsing has since grown from that single problem space and can now be found in Jabber software everywhere. Want to find ...