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 recently in the Real-time CORBA and Faulttolerant CORBA specifications. This paper provides four contributions to the study of fault-tolerant CORBA middleware for performancesensitive 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 Faul...
Balachandran Natarajan, Aniruddha S. Gokhale, Shal