CAREER: Integrated Fault Tolerance and Real-Time Support for Middleware Applications

本项目以CORBA中间件标准为载体，研究分布式中间件应用的实时性和容错性的组合。虽然最初的方法将适用于CORBA，但其结果将适用于其他中间件，如Java。该项目的主要科学贡献是描述了当中间件应用程序同时需要实时和容错支持时发生的精确权衡，以及可用于解决这些权衡的体系结构和策略。该项目的主要技术贡献是一套用于构建实时容错系统的新实践和算法，以及用于消除中间件应用程序中的不确定性的工具，目的是同时满足实时可预测性和容错一致性要求。该项目加深了我们对实时和容错之间的精确迁移和复杂交互的技术理解，从而帮助减少继续构建的专有脆性系统的数量。该项目有可能影响技术水平和实践水平，使未来基于COTS的关键任务应用程序能够同时获得实时和容错支持。认识到应用程序不同的可靠性需求，该项目的独特之处在于它提供了混合和匹配不同的容错机制的机制，允许定制系统的可信性。通过参与对象管理小组等组织，该项目的结果将可用于加强当前和未来的容错和实时硬件标准。该项目的内容将被纳入课程，以使学生接触到可靠性和实时这两个交叉问题。如果学生接触到的不是单纯的“无能”，而是多个“无能”之间的冲突和取舍，他们将成为更好、更有鉴别力的软件/系统架构师，他们可以被委托来构建未来的关键任务系统。

This project exploits the CORBA middleware standard as a vehicle forexploring the composition of real-time and fault tolerance fordistributed middleware applications. Although the initial approachwill apply to CORBA, the results will be applicable to othermiddleware, such as Java. The primary scientific contributions ofthis project are the description of the precise trade-offs that occurwhen both real-time and fault tolerance support are required for amiddleware application, along with an architecture and strategies thatcan be used to resolve these trade-offs. The primary technicalcontributions of the project are a new set of practices and algorithmsfor building real-time fault-tolerant systems, and tools forsanitizing non-determinism in middleware applications, with the aim ofmeeting both real-time predictability and fault-tolerant consistencyrequirements.This project furthers our technical understanding of the precisetrade-offs and complex interactions between ``-ilities'' such asreal-time and fault tolerance, thereby helping to reduce the number ofproprietary brittle systems that continue to be built. The projecthas the potential to influence the state of the art and thestate of the practice, enabling future COTS-based mission-criticalapplications to be developed with simultaneous real-time andfault-tolerant support. Recognizing that applications vary in theirdependability needs, this project is unique in that it providesmechanisms to mix-and-match the different fault tolerance mechanismsin a manner that allows for the customization of the system'sperceived dependability.Through participation in organizations such as the Object ManagementGroup, the results of this project will be made available to hardenongoing and future standards on fault tolerance and real-time formiddleware. Elements of this project will be incorporated intocurricula in order to expose students to the cross-cutting concerns ofboth reliability and real-time. Students who are exposed to not justone ``-ility'', but to the conflicts and trade-offs between multiple``-ilities'', will make better and more discriminating software/systemarchitects who can be entrusted to build the mission-critical systemsof the future.