Applying a real-time OS to transmission equipment management

Advances in transmission equipment functionality have been accompanied by an increase in the scale of software running on these systems. To reduce the software development burden and achieve more efficient software maintenance, NTT decided to introduce a real-time operating system (OS) and port application programs across different systems. This paper presents the software interface structure and design principles adopted in OS introduction for transmission equipment. Covered in this discussion are the Basic OS interfaces for hiding differences in hardware specifications, the Extended OS interfaces providing logicalized common functions, and the AP interface forming the platform for creating applications. Also discussed are some technical features in implementing the OS for transmission equipment, including the methods of implementing communication control and OAM management and a message tracer for tracing communications between applications. These techniques have contributed to the portability of applications developed on this OS.