Binarians, unitarians and contrarians
It's estimated that there are at least a dozen binary XML formats already in use or in development today. If it does go ahead with an effort to speed up XML, the W3C will seek to create a single group-sanctioned binary format, rather than have several formats for specific purposes, said Quin.
"We hope if we publish something that meets the needs of many of these people, they will switch to whatever we publish. And indeed many have said they would do that," said Quin.
Others argue that multiple binary formats are needed. Michael Rys, a program manager for Microsoft's SQL Server database and a member of the W3C's XML Query Working Group, said that Microsoft does not favour the W3C creating a single binary XML format.
In a blog posting following the Boston meeting, Rys said that if there must be a binary XML standard, then the W3C should "do it right".
"There will be more than one binary XML format," Rys wrote. The W3C is "very unlikely to define a format that optimises a dozen, partially conflicting goals."
Another concern facing the W3C is whether a substantial change to the XML standard, such as a binary XML format, will be widely adopted — or ignored, as existing parsers would have to be upgraded to make sure computers can read both text and binary formats. Without broad adoption of the specification, software developers will be less likely to make use of the speedier XML.
XML proponents note that the latest XML 1.1 specification has been adopted more slowly than hoped. Microsoft, for example, has decided not to support that specification for fear of causing compatibility problems with applications that use the XML 1.0 standard, according to Rys.
Iona's Newcomer noted that there are several different options for making XML go faster. Some approaches would require a complete rewrite of existing parsers, rather than relatively minor changes with a simpler upgrade path, he noted.
If the W3C votes in favour of pursuing a binary XML standard, a working group could be formed as early as this summer and take up to three years to complete a specification, Quin said. To address concerns and solicit feedback, the W3C is scheduling public hearings at various conferences worldwide.
"This one has some controversial aspects," Quin said, "so I would not like to predict the outcome at the moment."
