Quantification of autonomy on multidatabase systems

Abstract

Amultidatabase system is an interconnected collection of autonomous databases each managed by an autonomous database management system (DBMS). When integrating multiple DBMSs, the key is the autonomy of the underlying participants. Much research has been undertaken in the past five years aimed at describing and building an integrated multidatabase system, but to date the termautonomy has only been defined intuitively. This article provides a rigorous definition for autonomy tailored to the multidatabase environment specifically but applicable to any system environment that involves the collaboration of autonomous participants. The major contribution of this article is a technique that measures autonomy along multiple dimensions so a single numeric value describing the amount of autonomy violated by a particular system design is quantified. This has a two-fold implication. First, the technique described forces researchers to consider autonomy from several different aspects that may not be the central focus of their research, but must be considered because assumptions made regarding one aspect of a system may have implications in other areas. Second, the value can be used as a measure for direct comparison among different systems or proposals. Finally, the article demonstrates the quantification technique's applicability by applying it to several recent multidatabase research efforts.