Algorithms and programming models for efficient representation of XML for Internet applications

Abstract

XML is poised to take the World-Wide-Web to the next level of innovation. XML data, large or small, with or without associated schema, will be exchanged between increasing numbers of applications running on diverse devices. Efficient storage and transportation of such data is an important issue. We have designed a system called Millau and a series of algorithms for efficient encoding and representation of XML structures. In this paper we describe some of the newer algorithms and APIs in our system for compression of XML structures and data. Our compression algorithms, in addition to separating structure and text for compression, take advantage of the associated schema (if available) in compressing the structure. We also quantify XML documents and their schema with the purpose of defining a decision logic to apply the appropriate compression algorithm for a document or a set of documents following a particular schema. Our system also defines a programming model corresponding to XML Document Object Model and Simple API for XML streams and documents in compressed form. Our experiments have shown significant performance gains of our algorithms and APIs. We describe some of these results in this paper. We also describe some Web applications based on our system.