An Evaluation of Information Consistency in Grid Information Systems

A Grid information system resolves queries that may need to consider all information sources (Grid services), which are widely distributed geographically, in order to enable efficient Grid functions that may utilise multiple cooperating services. Fundamentally this can be achieved by either moving the query to the data (query shipping) or moving the data to the query (data shipping). Existing Grid information system implementations have adopted one of the two approaches. This paper explores the two approaches in further detail by evaluating them to the best possible extent with respect to Grid information system benchmarking metrics. A Grid information system that follows the data shipping approach based on the replication of information that aims to improve the currency for highly-mutable information is presented. An implementation of this, based on an Enterprise Messaging System, is evaluated using the benchmarking method and the consequence of the results for the design of Grid information systems is discussed.