Describes the concepts and model of ROS. It uses ASN.1 to specify information object classes corresponding to the fundamental concepts of ROS, such as operation and error. This in turn provides a notation so that designers can specify particular instances of those classes, e.g. particular operations and errors. It provides a generic set of PDUs which can be used when realizing ROS concepts between objects remote from one another. These PDUs are used in the OSI realization of ROS, which are specified in the respective Recommendations (International Standards). Partial revision of ISO/IEC 9072-1 und ISO/IEC 9072-2.