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Standards and protocols
Standard for interference limits Increasing use of data processing and electronic office equipment means a corresponding increase in the generation of periodic binary pulsed electrical/electronic wave forms, which can cause harmful interference to radio reception. Yet, at the moment, there is no agreed international standard specifying the limits of permitted radio interference caused by computers in either the domestic or commercial area. However, BS 6527 Specifica-
tion for limits and measurements of spurious signals generated by data processing and electronic office equipment, published by the British Standards Institution, aims to provide some guidance for users within the UK. The standard is the first to specify limits for the levels of these spurious signals in order to reduce to an acceptable level the probability of the incidence of radio interference from sources in both
Protocol analysers for the field Two protocol analysers aimed at the development, installation and maintenance of data communications systems have been introduced by the Industrial Systems Department of Panasonic Industrial: The portable VP-3682P is for trouble shooting and fault analysis in the field. It is capable of recording all data sent and received in a network system in its 64 kbyte memory and then displaying information on the integral CRT. Protocols such as the CCITT X.25 are supported, and data can be displayed in either ASCII or HEX. The analyser also includes FCS and parity checking, selective triggering and automatic setting.
The second model, the VP3686P, in addition to real time data monitoring can perform simulation and translation of protocols. The VP-3686P makes it possible to analyse even complicated procedures through 'idle suppress', H DLC, CClTTX.25 protocol translation and selective trace functions. Simulation is particularly useful for some tests such as physical level of CCITT X.25, data link levels and packet levels. As the data link level is generated automatically, packet level can be tested without regard to the link level. (Industrial Systems Department, Panasonic Industrial UK Limited, 280/290 Bath Road, Slough, Berks. SL? 6JG, UK) []
The VP-3686P offers protocol translation and simulation
vol 8 no 2 april 1985
commercial (class A) and domestic (class B) areas. Measurement of limits is at mains terminals in the frequency range 0.15MHz to 30 MHz and of field strength from 30 MHz to 1 000 MHz. These limits and methods of measuring them are based on work currently in progress within the International Special Committee on Radio Interference (CISPR). (Sales Department, British Standards Institution, Linford Wood, Milton Keynes MK14 6LE, UK. Tel: 0?-629 9000) []
British OSI standards The British Standards Institution (BSI) has published a new standard of significance to suppliers and users of information technology equipment that defines the internationally-agreed framework within which open systems interconnection (OSI) standards are being developed. Entitled BS 6568 Description of basic reference model for open systems interconnection, it is the UK equivalent of ISO 7498 and is the first fruit of a major international programme to produce standards that allow communication between computer systems of different types and manufacture. BSI will subsequently publish, as Drafts for Development, the texts of other open systems interconnection standards (now in preparation within ISO) that are relatively stable, thus ensuring that this information is readily available pending final agreement on the standards concerned. Since the ISO texts may be subject to changes resulting from the ballot procedure, the BS Drafts for Development will be updated at suitable intervals. They will be available under the SOS scheme for BSI subscribing members (which includes an automatic updating service), as well as from the BSI Sales Department. (Sales Department, British Standards Institution, Linford Wood, Milton Keynes MK14 6LE, UK. Tel: 01-629 9000) []
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tion for limits and measurements of spurious signals generated by data processing and electronic office equipment, published by the British Standards Institution, aims to provide some guidance for users within the UK. The standard is the first to specify limits for the levels of these spurious signals in order to reduce to an acceptable level the probability of the incidence of radio interference from sources in both
Protocol analysers for the field Two protocol analysers aimed at the development, installation and maintenance of data communications systems have been introduced by the Industrial Systems Department of Panasonic Industrial: The portable VP-3682P is for trouble shooting and fault analysis in the field. It is capable of recording all data sent and received in a network system in its 64 kbyte memory and then displaying information on the integral CRT. Protocols such as the CCITT X.25 are supported, and data can be displayed in either ASCII or HEX. The analyser also includes FCS and parity checking, selective triggering and automatic setting.
The second model, the VP3686P, in addition to real time data monitoring can perform simulation and translation of protocols. The VP-3686P makes it possible to analyse even complicated procedures through 'idle suppress', H DLC, CClTTX.25 protocol translation and selective trace functions. Simulation is particularly useful for some tests such as physical level of CCITT X.25, data link levels and packet levels. As the data link level is generated automatically, packet level can be tested without regard to the link level. (Industrial Systems Department, Panasonic Industrial UK Limited, 280/290 Bath Road, Slough, Berks. SL? 6JG, UK) []
The VP-3686P offers protocol translation and simulation
vol 8 no 2 april 1985
commercial (class A) and domestic (class B) areas. Measurement of limits is at mains terminals in the frequency range 0.15MHz to 30 MHz and of field strength from 30 MHz to 1 000 MHz. These limits and methods of measuring them are based on work currently in progress within the International Special Committee on Radio Interference (CISPR). (Sales Department, British Standards Institution, Linford Wood, Milton Keynes MK14 6LE, UK. Tel: 0?-629 9000) []
British OSI standards The British Standards Institution (BSI) has published a new standard of significance to suppliers and users of information technology equipment that defines the internationally-agreed framework within which open systems interconnection (OSI) standards are being developed. Entitled BS 6568 Description of basic reference model for open systems interconnection, it is the UK equivalent of ISO 7498 and is the first fruit of a major international programme to produce standards that allow communication between computer systems of different types and manufacture. BSI will subsequently publish, as Drafts for Development, the texts of other open systems interconnection standards (now in preparation within ISO) that are relatively stable, thus ensuring that this information is readily available pending final agreement on the standards concerned. Since the ISO texts may be subject to changes resulting from the ballot procedure, the BS Drafts for Development will be updated at suitable intervals. They will be available under the SOS scheme for BSI subscribing members (which includes an automatic updating service), as well as from the BSI Sales Department. (Sales Department, British Standards Institution, Linford Wood, Milton Keynes MK14 6LE, UK. Tel: 01-629 9000) []
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