Open Systems Interconnection

The subject of Open Systems Interconnection (OSI) standardization is becoming increasingly important to the telecommunications and information processing communities. A number of OS1 standards have been completed, others are near completion, and initial product offerings by vendors have begun. This paper briefly defines what OS1 is, the interrelationships of the various standards bodies, and the goals and benefits to users, vendors, country post telephone and telegraph bodies, common carriers, and governments. The IBM view of OS1 and how it relates to Systems Network Architecture is also discussed. 0 pen Systems Interconnection (OSI) is an international standards activity that primarily defines formats and protocols to interconnect systems that have different architectures provided by different suppliers. OSI can also be used to interconnect sophisticated devices that operate on a peer-to-peer basis. This activity has had the strong support and involvement of manufacturers, users, governments, common carriers, and the government agencies for Post, Telephone, and Telegraph (PTTS). IBM has actively supported and participated in the OSI standards efforts since their start and has made numerous contributions to the technical work. OSI activity was initiated in March 1977 by ISO, the International Organization for Standardization, and interest and participation in it have continued to grow. The objectives of os1 are Interconnection of the systems of different vendors Coordination of standardization activities in tele-Promotion of new information systems business communications and information systems OSI standards are beginning to reach maturity. Many are approved, and a complete set is expected to be approved by 1988. OSI standards are a major activity not only for ISO but also in all of the major regional and international standards organizations, including the International Telegraph and Telephone Consultative Committee (CCITT), the European Computer Manufacturers Association (ECMA), and the Institute for Electrical and Electronics Engineers (IEEE). Since its inception, OSI has grown in technical concept from the initial development of a telecommunications base to the current scope of effort, which includes subjects such as file transfer, job transfer, and message handling. The telecommunications base has expanded to incorporate technical innovations such as local-area networks (LANS) and integrated services digital networks (ISDNS). OSI has the potential to create significant business opportunities in the information processing industry, especially in user multivendor system environments and in government procurements. Manufacturers are beginning to announce support of OSI standards that have reached completion. User groups are forming for the purpose of understanding and evaluating the usage …