A software architecture for intelligent synthesis environments

NASA's Intelligent Synthesis Environment (ISE) program is a grand attempt to develop a system to transform the way complex artifacts are engineered. This paper discusses a "middleware" architecture for enabling the development of ISE. Desirable elements of such an Intelligent Synthesis Architecture (ISA) include remote invocation; plug-and-play applications; scripting of applications; management of design artifacts, tools, and artifact and tool attributes; common system services; system management; and systematic enforcement of policies. A typical middleware foundation for an ISA is a distributed object technology such as CORBA (Common Object Request Broker Architecture). I argue that such an architecture can be profitably extended by enabling "plug-and-play" insertion of new policies into the system. I describe the Object Infrastructure Framework, an Aspect Oriented Programming (AOP) environment for developing distributed systems that provides policy insertion. This technology can be used to enforce policies such as maintaining the annotations of artifacts, particularly the provenance and access control rules of artifacts; performing automatic datatype transformations between representations; supplying alternative servers of the same service; reporting on the status of jobs and of the system; conveying privileges throughout an application; supporting long-lived transactions; maintaining version consistency; and providing software redundancy and mobility.