From sdw at lig.net Thu Feb 9 14:38:46 2006 From: sdw at lig.net (Stephen D. Williams) Date: Thu Feb 9 14:38:59 2006 Subject: [esXML-dev] Efficiency Structured XML - esXML 0.9 specification available Message-ID: <43EB9A46.3010608@lig.net> The specification for esXML has been updated significantly. The current specification includes the ability to be tuned for processing, compactness, and processing+compactness optimized application scenarios. Several innovative ideas are included, especially the MetaStructure Instance (MSI) representation of information that is "externalized" from a "complete" instance of a data object. esXML supports documents or objects that are any place on a spectrum from self-contained and self-describing (a la text-based XML, with or without a schema) to a fully-externalized data representation. The latter externalizes various typing, structure, and metadata into an MSI, leaving a highly compact and optionally compressed instance, similar to PER encoding. One ore more MSIs + a referring instance are equivalent to a self-contained, self-describing instance. This mechanism helps unify the various styles of data encoding under a theoretical framework, referred to as "externalization", for thinking about what is or is not present in an instance. In many legacy cases, for instance, knowledge about the structure of an instance is embedded in the actual code that knows how to interpret it. This is important when comparing various approaches to general purpose data representation. The MSI is designed to allow any template, schema language, or automated encoding design process to produce metadata that any encoder and decoder can use to access or convert data. This allows both the specification and codecs to be simplified while allowing the use of schema-based encoding that can evolve independently. Comments, discussion, and collaborative development are welcome. See: http://esxml.org http://esxml.org/esxml-specification.html sdw Stephen D. Williams http://sdw.st sdw@lig.net swilliams@hpti.com