Distributed XML Design

TL;DR

This paper develops a theoretical framework for designing distributed XML documents, focusing on type propagation and enforcement across multiple machines, and analyzes the complexity of related typing problems.

Contribution

It introduces a formal theory for distributed XML design, addressing type propagation and enforcement, and studies the computational complexity of these problems.

Findings

Fundamentals of distributed XML design theory established.

Complexity analysis of typing problems provided.

Framework supports both top-down and bottom-up design approaches.

Abstract

A distributed XML document is an XML document that spans several machines. We assume that a distribution design of the document tree is given, consisting of an XML kernel-document T[f1,...,fn] where some leaves are "docking points" for external resources providing XML subtrees (f1,...,fn, standing, e.g., for Web services or peers at remote locations). The top-down design problem consists in, given a type (a schema document that may vary from a DTD to a tree automaton) for the distributed document, "propagating" locally this type into a collection of types, that we call typing, while preserving desirable properties. We also consider the bottom-up design which consists in, given a type for each external resource, exhibiting a global type that is enforced by the local types, again with natural desirable properties. In the article, we lay out the fundamentals of a theory of distributed XML design, analyze problems concerning typing issues in this setting, and study their complexity.