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This article focuses on the proposed USA Standard, which presents control procedures for the data communication systems. This employs the USA Standard Code (SC) for Information Interchange. It is intended for systems that are controlled through the use of the communication control characters provided in USASCII. Other standards have been adopted or are being developed which prescribe the character structure, bit sequencing, signaling speed, message format, and other parameters vital to the communication of information in a data system. In the development of this standard both historical and present data communication practices were considered. In addition, consideration was given to the requirements for future systems and to the applicable standards being developed internationally. This standard is intended for systems that are controlled through the use of the communication control characters provided in USASCII. This standard specifies a variety of data communication control procedures to meet the needs of data communication links having different configurations or complexity.

The decomposition of a complex data transmission system into segments and the identification of the terminal configurations employed on each segment appear to offer promise as a powerful tool for permitting and clarifying measurements and comparisons of the performance of like system segments, and for describing the features of systems which are significant to performance measurements. Many problem areas remain, however, for further study. For example, the question of combining the individual performance measures of a multisegment, multi-mode-of-operation system into a meaningful measure of total systems performance appears quite formidable. It is the intent of the Task Group to approach these problems of performance measurement gradually and to resolve them first for the simpler systems before proceeding to complex system configurations. Although the techniques which this Task Group has evolved for system description may appear to be voluminous or even redundant when applied to very simple configurations, they are orderly, and every effort has been made to seek and exploit the "common denominators" of data transmission systems having arbitrary degrees of complexity. We doubt that much further compaction can be realized without, severely curtailing or destroying the generality and (hopefully) universal applicability of these methods. The format which has been described is admittedly incomplete. It is suggestive rather than exhaustive. It is believed that its chief virtue lies in the identification of an orderly succession of levels of abstraction which permits the regular decomposition of highly complex systems into functional subgroupings having a size structure within the span of human attention. The details of description outlined within these subgroupings require further study and elucidation and it will probably always be necessary for the system describer Io employ good judgment and imagination in extending the scope of description in those areas where new advances, unique applications and/or common sense so dictate. [ABSTRACT FROM AUTHOR]

The article presents information on the proposed American Standard for digital data transmission speeds, developed by the Subcommittee of the American Standards Association Sectional Committee X3. It defines the standard signaling speeds used for equipments designed to operate with up to 8 parallel data bits per character. These speeds are applicable on the received data and transmitted data circuits at the interface between data processing terminal equipment and data communications equipment. It suggests that the establishment of specific speeds ensures the compatibility between communication channels and data terminal equipments of data communication systems.

Reports on the expansion of the ARPANET, a system of interconnected computers set up by the U.S. Department of Defense's Advanced Research Projects Agency (ARPA) or for users involved in research financed by the U.S. government. Description of the system; Information on how the interface message processor solved in the incompatibility of the computers used in the network; Views of Lawrence G. Roberts, diretor for information-processing techniques of the ARPA, on the ARPANET.