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Title: A truly distributed database architecture for hard real-time systems
Author: Al-Rashoud, B. S. A.
Awarding Body: University of Wales Swansea
Current Institution: Swansea University
Date of Award: 1997
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In any system, good management depends on access to good information. In real-time systems, however, it is not enough to have access to correct data; that data should also be referenced to time. In distributed systems the validity of data is affected by many factors. Besides the errors that can occur because of hardware or software failures, inconsistency can occur through other factors such as uncontrolled access to distributed data, or because of uncompleted access to duplicated data. Many factors contribute to the incorrectness of data in the domains of value and time. This thesis sets out to investigate the requirements for handling hard real-time data in distributed databases, and suggests an architecture that allows access to such data in a timely and controllable manner. The nature of real-time data, and the requirements for accessing it in the presence of hard real-time and distributed-access constraints, are investigated. Current techniques that maintain the correctness of concurrent access to data in systems were investigated and found to be inappropriate in hard real-time situations. The need for suitable real-time techniques is therefore obvious and urgent, and so an approach that maintains the correctness of distributed access to data under real-time constraints, is proposed here. An experimental attempt to implement and measure the effectiveness of the proposed techniques using an existing environment is described, followed by a proposal for a more complete, fieldbus-based environment. The thesis concludes by showing the results of the work, as well as further research that could be done to obtain solutions to the problems described and partially solved in this thesis.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available