Building Evolvable Systems: The ORBlite Project

Hewlett-Packard has been building distributed and parallel systems for over two decades. Our experience in building manufacturing test systems, medical information systems, patient monitoring systems, and network management systems has exposed several requirements of system and component design that have historically been recognized only after a system has been deployed. The most critical of these requirements (especially for systems with any longevity) is the need for the system and system components to be able to evolve over time. The ORBlite distributed object communication infrastructure was designed to meet this requirement and has been used successfully across HP to build systems that have evolved along several dimensions. The ORBlite framework supports the piecewise evolution of components, interfaces, communication protocols, and even programming APIs. This piecewise evolution enables the integration of legacy components and the introduction of new features, protocols, and components without requiring other components to be updated, ported, or rewritten. A vertical slice through the ORBlite framework forms the basis of HP’s ORB Plus product, a strict implementation of the CORBA 2.0 standard.