DOORS: towards high-performance fault tolerant CORBA

An increasing number of applications are being developed using distributed object computing middleware, such as CORBA. Many of these applications require the underlying middleware, operating systems, and networks to provide end-to-end quality of service (QoS) support to enhance their efficiency, predictability, scalability, and fault tolerance. The Object Management Group (OMG), which standardizes CORBA, has addressed many of these application requirements in the Real-time CORBA and Fault-Tolerant CORBA specifications. We provide four contributions to the study of fault-tolerant CORBA middleware for performance-sensitive applications. First, we provide an overview of the Fault Tolerant CORBA specification. Second, we describe a framework called DOORS, which is implemented as a CORBA service to provide end-to-end application-level fault tolerance. Third, we outline how the DOORS´ reliability and fault-tolerance model has been incorporated into the standard OMG Fault-tolerant CORBA specification. Finally, we outline the requirements for CORBA ORB core and higher-level services to support the Fault Tolerant CORBA specification efficiently