Subject: [sacm] XMPP-Grid Topic/subtopic vocabulary

From: "Adam W. Montville" <[email-masked]>
Date: Sat, 6 Sep 2014 07:33:14 -0500

I'm reading through section 3.5 of the -00 XMPP-Grid draft [1] and have a question about topics/subtopics.  

Section 3.5 states, “…the providers (publishers) of the capabilities define the schemas for the data exchanged.  The capability provider shall also define the version, the available queries and notifications that it can support.  The capability provider publishes the messages to one or more XMPP Topics, that is requests XMPP-Grid to create dynamically…”

Creation of topics dynamically may cause interoperability issues between implementations.  Suppose, for example, that Vendor A registers its component with the Grid as providing “configuration assessment” data, and Vendor B registers its component with the Grid as providing “configuration” data.  Then, when a consumer queries the Grid for a list of capabilities, it will see a list of two similar, but distinct, topics ("configuration assessment" and “configuration”).

Is it expected that the languages supported by each topic (i.e. the specific schemas supported) will be what’s really depended upon?  If so, then what is the purpose of having the top-level capability at all?  If not, then how do we expect to achieve interoperability of components without having some a priori, controlled vocabulary of capabilities?

Adam

[1] http://datatracker.ietf.org/doc/draft-salowey-sacm-xmpp-grid/