Dissemination of heterogeneous XML data in publish/subscibe systems

Abstract

The publish-subscribe paradigm is an effective approach for data publishers to asynchronously disseminate relevant data to a large number of data subscribers. A lot of recent research has focused on extending this paradigm to support content-based delivery of XML data using more expressive XML-based subscription specifications that allow constraints on both data contents as well as structure. However, due to the heterogeneous data schemas used by different data publishers even for data in the same domain, an important challenge is how to efficiently and effectively disseminate relevant data to subscribers whose subscriptions might be specified based on schemas that are different from those used by the data publishers. In this paper, we examine the options to resolve this schema heterogeneity problem in XML data dissemination, and propose a novel paradigm that is based on data rewriting. Our experimental results demonstrate the effectiveness of the data rewriting paradigm and identifies the tradeoffs of the various approaches.