CAN/CSA-Z243.101-89 (R2018)

Preface This is the first edition of CSA Standard CAN/CSA-Z243.101, Information Processing Systems-Open Systems Interconnection-LOTOS-A Formal Description Technique Based on the Temporal Ordering of Observational Behaviour. This CSA Standard is adopted from the ISO International Standard 8807. As a member country of ISO/IEC JTC1, Canada participated actively in this work through the CSA Technical Committee on Open Systems, which, in addition to its role as a National Standards Committee, is also the Canadian Advisory Committee (CAC) on ISO/IEC JTCl/SC21. This Standard was reviewed and adopted by the CSA Technical Committee on Open Systems under the jurisdiction of the Standards Steering Committee on Information Technology, and was formally approved by these Committees. The Standard has been approved as a National Standard of Canada by the Standards Council of Canada. Scope and Field of Application This International Standard defines the syntax and semantics of the Formal Description Technique LOTOS. LOTOS is in general used for the formal description of distributed, concurrent information processing systems. In particular LOTOS can be used to describe formally the service definitions and protocol specifications of the layers of Open Systems Interconnection (OSI) architecture described in ISO 7498, and related standards, and conformance tests for implementations of OSI protocols and/or OSI functions. It can also be applied for the formal description of other distributed systems, such as telephone switching networks.