Commercially available, DO-178B level a certifiable, hard partitioned, posix compliant real-time operating system and TCP/UDP compliant ethernet stack software

With the move towards large scale avionics systems integration, the functionality demands required to meet system needs along with the market moving towards open system architectures(OSA) have exceeded the ability of avionics equipment suppliers to support these needs with proprietary solutions. Selection of a real-time operating system(RTOS)can have a dramatic impact on the ultimate capability of a product or system, from both the functionality as well as supportability aspects. In addition, selection of the system interconnect along with the RTOS will dictate the flexibility, scalability and reusability of the system architecture. However until recently, neither an RTOS with robust functionality such as those provided with a POSIX API nor one with an adaptable system interconnect such as Ethernet existed in a commercially available, DO-178B safety criticality Level A certifiable state. This paper will discuss how a POSIX complaint RTOS with hard partitioning, combined with a TCP/UDP complaint Ethernet stack, both of which are commercially available, can provide 'work station class' functionality in a DO-178B Level A environment. It will look at the functionality required, desirable attributes and capabilities, as well as how to meet the requirements and objectives of an Open Systems Architecture. Finally, the paper will take a brief look at a typical implementation.