Transaction validation for XML documents based on XPath

Abstract

Whenever mobile devices modify copies of common XML data, then synchronization of multiple user transactions accessing this data is a key problem. However compared to standard XML database systems, transaction synchronization has to solve new problems, i.e. it has to manage lost connections and it furthermore should reduce data exchange over small bandwidth client connections for the purpose of synchronization. In order to avoid locks that are assigned to transactions of "lost" clients, we suggest to use an optimistic approach to synchronization. In order to reduce the data exchange for synchronization, we furthermore suggest to exchange XPath expressions instead of larger XML fragments wherever possible. This allows us not only to treat lost connections more flexible but also to operate efficiently on mobile devices with small bandwidth connections to a server.