March meeting of the DC XML Users Group

Last month Karanjit Siyan, from NIST, spoke to the DC XML Users Group about XML schema basics.

W3C schemas are largely replacing DTDs because W3C schemas have better support for namespaces, finer granularity, description of data types, and are more useful for language bridges.

Siyan proceeded to review content models (empty, simple, complex, and mixed) and how they are used in W3C schemas. At the end of his presentation there was a lively discussion about the difficulty of using parsers with W3C schemas.

Diane Lewis of the Office of Justice Programs, was the next speaker. (The DC XML Users Group has a tradition of double features.) Her presentation was wonderfully titled Working towards usable standards at the Dept. of Justice. It is not often you get such hype-free presentations.

For reasons which must be obvious, much of the data at the Dept. of Justice is from statues and pleadings. Unfortunately the Federal Court system puts everything into PDF format, making it difficult to exchange data with other systems. The Justice Dept. also receives are great deal of data from state and local courts and police departments, thus the keen interest in developing, and promoting the adoption of, standards.

During the question period a member of the audience asked about XML and security. After everyone enjoyed a hearty laugh, Lewis explained that security was layered on top of the XML schemas; but that security is an issue that standards bodies need to address. I know the federal XML work group is discussing this very issue.