Protecting the quality of service of existing information systems

Organizations that offer external access to their data need a mechanism that ensures a desired level of service for local users. We propose such a mechanism, called the provider agent (PA) architecture, that protects local users by ensuring a (DBA specified) quality of service for local requests in the face of computational demands made by external requests. The PA is a general purpose solution that enhances most information systems currently available. The novelty of our approach is the combination of request profiling with load control mechanisms to improve both protection and performance, while not requiring any modifications to the underlying information system. We demonstrate the effectiveness of the proposed techniques with a prototype PA for a commercial DBMS.