Global information systems consist of asynchronous, autonomous components that are open and distributed. These components will need to handle multiple media types and satisfy varying Quality-of-Service(QoS) requirements such as responsiveness, reliability, availability, security and cost-effectiveness. Adapting to changing system conditions and application requirements is often difficult and error prone. Distributed systems services can potentially interfere with each other in non-compatible ways, especially in the presence of QoS requirements.
This research plan proposes the formulation, specification and implementation of a new paradigm for developing QoS-enabled customizable middleware for the global information infrastructure. The customizable and safe distributed systems middleware infrastructure developed, called ComPOSE/Q (Composable Open Software Environment with QoS), has the ability to effectively address the challenges posed by the evolving infrastructure. The primary distinguishing feature of ComPOSE/Q is that it provides "composable distributed resource management", i.e., it allows the concurrent execution of multiple resource management policies in a distributed system in a safe and correct manner. Safe composability of resource management mechanisms is required to provide cost-effective QoS in a wide area distributed infrastructure. The research develops a semantic model for representing QoS, middleware components and techniques for reasoning about their interaction. The work is based on a formal meta-architectural model of middleware that permits customization of policies for placement, scheduling synchronization and management of components. The meta-architecture allows for the separate specification of system policies from application requirements and hence permits either to be customized independently to adapt to changing system conditions and application requirements. To ensure non-interference, CompOSE/Q implements core resource management services -- remote creation, distributed snapshot and directory services that are composable and can be used as a basis for creating more complex activities. The proposed methodology will be validated by using the CompOSE/Q middleware to develop systems support for network-centric and mobile computing environments.
The accompanying educational objectives are to strengthen the graduate and undergraduate computer science curriculum at the University of California, Irvine in the principles, practice and applications of wide-area distributed computing and multimedia technologies. This will involve the establishment of an Instructional Multimedia Laboratory that facilitates teaching both introductory and advanced courses in multimedia, distributed systems and information management. The long-term vision of the lab is to catalyze multidisciplinary application-oriented endeavors that are increasingly the driving force for innovative research as the world becomes highly interconnected and computerized.
