The days are long gone when a real-time operating system (RTOS) was simply a small kernel providing basic services such as task scheduling and reliable inter-task communications. Today's real-time operating systems are expected to perform a wide variety of functions ranging from managing real-time communications to providing a reliable foundation for higher level applications. In essence, today's real-time operating systems provide the foundation for complete software platforms that are increasingly purpose-built for specific applications.

What many embedded developers may not realize is that RTOS software architecture plays a pivotal role in meeting the specific needs of a particular application. Factors such as whether the RTOS is monolithic or based on a microkernel, whether it uses sockets, and whether it enforces a specific programming model can make a significant difference in the types of applications that best suit the RTOS. Enea® OSE® has been designed from the ground up for the fault tolerant distributed systems commonly found in telecommunications equipment, from mobile phones to radio base stations. This paper discusses the OSE architecture and design philosophy, and how that benefits telecommunications oriented applications.