In today's post from Eric's weblog, I found a link to the Sun's Java implementation of a new OASIS standard, XACML: eXtensible Access Control Markup Language, which also has been released on SourceForge, open source.

I wonder how or if this supercedes or otherwise relates to Information and Content Exchange (ICE)? XACML is certainly a less memorable acronym than ICE!

With iCites, there are a couple modules for content access and data exchange. These have to do with access permissions, digital rights expression, and privacy policy expression. In general, I am imagining uses simpler than what is possible with XACML, ICE, and P3P.

I am thinking about simpler things like access control lists, a link to a terms of use / copyright (and/or a Creative Commons license), and a link to a privacy statement. Of course, all of these should be available in machine readable formats (Creative Commons already offers RDF/XML metadata templates of its licenses).

So, since these iCite modules support machine readable (i.e., probably always some XML) policies, the modules should be flexible enough to support these more elaborate policy standards. And, while iCites won't by default have to support these elaborate interchange protocols, they could.

With XACML, the other thing I can't figure out is how exactly it works with "Subjects", i.e., users on access control lists. All of the examples on the XACML sites show policies for "All Subjects". Guess I will have to dig into it more.