Embedded computer systems play increasingly important roles in supporting the modern war fighter. The software on these systems tends to be organized as hierarchical layers, for which the lowest layers have hard-real-time and demanding throughput requirements. In the highest software layers, the software generally needs to be highly functional and flexible, but usually does not have real-time requirements or severe memory limitations. Intermediate layers in the hierarchy tend to demand intermediate levels of performance and compliance with less demanding levels of real-time, such as soft-real-time or firm-real-time. Between software layers, developers must engineer interfaces that provide efficient communication and coordination without allowing software at one layer from compromising the integrity of software running at other layers. This SBIR proposal addresses issues in the design and implementation of high-performance, secure and portable interfaces between layers of hierarchical software architectures. Based on the results of this research, prototype interfaces and tools to support the verification of compliance with interface requirements will be designed, prototyped, and evaluated. Benefits This technology benefits all developers of mission-critical embedded systems, including traditional mil/aero markets, but also automobile control, network infrastructure control and data planes, and rail transport. These technologies are especially valuable to the community because Ada suppliers are phasing out support for their Ada compilers, and the C and C++ languages do not scale as well to large software systems, especially systems that involve the mix of hard-real-time and soft-real-time components. Keywords Java, object-oriented, soft-real-time , real-time, hard-real-time, interface
