CAREER: Qos-enabled Customizable Middleware for Global Distributed Computing

全球信息系统由异步的、自主的、开放和分布的组件组成。这些组件需要处理多种媒体类型，并满足不同的服务质量（QoS）需求，如响应性、可靠性、可用性、安全性和成本效益。适应不断变化的系统条件和应用程序需求通常很困难，而且容易出错。分布式系统服务可能以不兼容的方式相互干扰，特别是在存在QoS需求时。本研究计划提出了一种新范式的制定、规范和实现，用于为全球信息基础设施开发支持qos的可定制中间件。所开发的可定制且安全的分布式系统中间件基础设施，称为ComPOSE/Q（具有QoS的可组合开放软件环境），能够有效地解决不断发展的基础设施带来的挑战。ComPOSE/Q的主要特点是它提供了“可组合的分布式资源管理”，也就是说，它允许在分布式系统中以安全和正确的方式并发执行多个资源管理策略。为了在广域分布式基础设施中提供经济有效的QoS，需要资源管理机制的安全可组合性。该研究开发了一个表示QoS的语义模型、中间件组件和它们相互作用的推理技术。这项工作基于中间件的正式元体系结构模型，该模型允许自定义放置、调度同步和组件管理的策略。元体系结构允许将系统策略规范与应用程序需求分开，因此允许对两者进行独立定制，以适应不断变化的系统条件和应用程序需求。为了确保不受干扰，CompOSE/Q实现了核心资源管理服务——远程创建、分布式快照和目录服务，这些服务是可组合的，可以用作创建更复杂活动的基础。所提出的方法将通过使用CompOSE/Q中间件来开发支持网络中心和移动计算环境的系统来验证。伴随的教育目标是加强加州大学欧文分校的研究生和本科生计算机科学课程，在广域分布式计算和多媒体技术的原理、实践和应用方面。这将包括建立一个教学多媒体实验室，以促进多媒体、分布式系统和信息管理方面的入门和高级课程的教学。实验室的长期愿景是促进多学科应用导向的努力，随着世界高度互联和计算机化，这些努力日益成为创新研究的推动力。

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. Distributedsystems 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 ofcomponents. 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-areadistributed 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.