Software survivability

Distributed software is highly vulnerable to the loss or degradation of hosts, networks, and processes due to physical and information warfare attacks, hardware and infrastructure failures, and software errors. Since the loss or degradation of components is inevitable, it is essential that critical systems behave well when subsystems fail. A system that can repair itself or degrade gracefully to preserve as much critical functionality as possible in the face of attacks and failures is called a survivable system. This report summarizes an architecture and software mechanisms to make software applications based on the popular Object Services Architecture (e.g., OMGs CORBA or Java/RMI/Jini) model far more survivable than is currently possible, while at the same time maintaining the flexibility and ease of construction that characterizes OSA-based applications