Aviation

Library network A network of 40 Ampex DM-9300 disc drives is now providing the database for a computer system that handles communications between over 2 100 terminals across the USA and a mirrored 6 000 Mbyte database. The database processor system was designed and built by Tandem Computers, USA, for OCLC, USA, a nonprofit-making firm that operates a computer-network used by I 500 libraries in 47 states. Academic, public, government, school, medical and law libraries use the OCLC system to catalogue books, order custom-printed catalogue cards and maintain location information on library materials. Each week, libraries catalogue over 250 000 books and other library materials from their remote terminals, and OCLC custom prints over 2M catalogue cards. The OCLC database contains information on more than 4M books and other library materials, and grows at a rate of about 20 000 new records (the average length is 600 byte) for library materials each week. The database is growing at the rate of about 3% a month. Tandem have provided a pair of NonStop computer systems: a fourprocessor system that handles frontend network supervision and a tenprocessor system for back-end data transfer between the database and the applications processor. The front-end network supervisor comprises four T/16 NonStop computers that handle communications from more than 2 100 terminals on over 65 leased multidrop lines. The back-end system uses ten T/16 NonStop computers to manage data transfer into and out of a mirrored 6 000 Mbyte database. The Ampex disc drives contain 6 000 Mbyte of primary data duplicated into immediate accessible mirror volumes to provide database integrity. Four levels of computers make up the OCLC system. The first level consists of D-116 concentrators accessed through leased multidrop lines by specially designed CRT terminals. The multiplexed data is then transmitted from the concentrators to the four-processor Tandem system serving

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as a front-end for the applications processors. Four Xerox Sigma 9 computers handle applications, and OCLC plans to add another Sigma 9. The ten-processor Tandem system supervizes communications between the applications computers and the database. Each processor module in the Tandem system includes 484 kbytes of main memory. One processor can address up to 256 peripherals. The Tandem system provides complete redundancy. Access to every peripheral device can continue despite the failure of any one processor. Every peripheral has two paths into the system and switching to the backup path is automatic in the event of a failure. Because of its dual port capability, every Ampex DM-9300 disc drive can be accessed through four independent paths to avoid isolating any disc, even under the worst conceivable system failure. Because of the redundant access paths, any peripheral can be removed or replaced or a new peripheral added without bringing the system down. This feature is especially important for OCLC's online computer network - when it is down, more than 2 000 library workers are made idle. OCLC is planning to increase the size of the front-end network from four to eight Tandem processors to communicate with other databases, such as those operated by Lockheed, the Systems Development Corporation and the New York Times. The equipment will make it possible for libraries to access these non OCLC databases from their specially designed OCLC terminals. (Ampex International,

Acre Road, Reading, Berhs., UK. Tel: Reading (0734) 864121)

[]

Packet service The Telenet Communications Corporation has initiated international packetswitched data-communications services to Israel, Singapore and the Philippines. The service enables terminal users overseas to connect on demand to computers using the Telenet packet network in the USA. International packet-switched service is now available in 22 countries in Europe, North America, Asia and the

Middle East. The overseas telecommunications administrations and the US international record carriers jointly provide the interconnection facilities between each participating country and Telenet in the USA. In Israel, the Ministry of Communications provides public dial-up access to Telenet-based computer systems. Charges for the service average $20/h, including the charge for the connection time and traffic charges based on the volume of data transmitted. Similar services from the Philippines are available at an average cost of $26/h. In Singapore, access to Telenet is available with both dial-up and leasedline arrangement from the Telecommunications Authority of Singapore. Rates average $22/h. About 225 computer centres, which are used for general database searching and time sharing as well as for intracorporate accounting and information management, are connected to the Telenet network. (Telenet Communica-

tions Corporation, 8330 Old Courthouse Road, Vienna, VA 22180, Austria. Tel: 703/827-9307) []

Aviation The UK Civil Aviation Authority has placed a contract with Software Sciences for the supply of a data-processing system for the Oceanic Area Control Centre at Prestwick controlling air traffic in the eastern part of the North Atlantic. The system is due to come into operation in 1982. The Centre (in conjunction with the Canadian Oceanic Centre at Gander Newfoundland) sets up twice daily a series of predetermined tracks across the North Atlantic. The tracks are calculated to provide the shortest journey time, and take into account the forecast weather. As the routes lie over water, radar coverage is not available, and the progress reported by aircraft is monitored at the Centre using arrays of paper flight-progress strips that have the data on individual flights needed for nonradar control. At Prestwick, at the moment, computer assistance is confined to printing the strips, exchanging a limited amount of data with the centre at Gander, and calculating the

computer communications

estimated elapsed flight times along the tracks. The new system will display flight data electronically. Aircraft position reports from air-ground communications stations and flight plans will be received and processed, and flight data will be exchanged with Gander and other ATC centres. Potential reduction of separation between aircraft will be detected and solutions proposed for consideration by the controller. The progress of flights will be monitored, and the controller alerted if, for instance, an aircraft fails to make its scheduled report. Predetermined tracks taking into account the forecast weather will be calculated. Data will be recorded continuously for statistical and incident analysis and to provide a means of rapid recovery from a system fault. To meet the design aim to restrict breaks in operational service to no more than one failure of more than 5 min in ten years, the hardware will consist of two equipment groups arranged as main and standby with special switching and the ability to restart quickly. Each group will be based on a DEC PDP 11/70 computer, and where possible, all the other hardware will be commercially available. The software will be mainly written in CORAL and the task is estimated at 75 man-years.

(Civil Aviation Authority, CAA House, 45-59 Kingsway, London WC28 6TE, UK. Tel: 01-379 7311) []

Supermarket modems Fine Fare has ordered Case modems, multiplexers and electronic switching to upgrade its distribution and stockcontrol system. The 9 600 bit/s modems will support leased and dialup circuits linking PDP-11 computers at each of six major depots with the head office computer. The PDP-1 ls support up to ten VDUs and printer terminals. Multiplexers are being installed to provide these terminals with access to the head office computer in the event of a local computer failure. To achieve the level of back up required by Fine Fare it is necessary to provide alternative network configurations for each depot. This has been accomplished by an electronic switching complex that can be operated by

vol 2 no 2 april 1979

nontechnical staff from a rotary switch. (Computer and Systems

Engineering Ltd, Woodcock Hill Estate, Harefield Road, Rickmansworth, Herts. WD3 IPL, UK. Tel: Rickmansworth 76699, [] Tx: 923325)

Cash and carry The Landmark group of wholesale cash and carry companies have bought an RTC 4560 Cash and Carry computer system. The system comprises a 32 kword minicomputer, 10 Mbyte disc storage for customer and product file information, four checkout stations, one goods inwards station, three highspeed printers, and one manager's console. The printer will be used to provide management reports on'goods received, to produce labels and to provide customers with detailed invoices.

(Real Time Control Lt~ Kebbell House, Carpenders Park, Watford, Harts. WD1 5BE, UK. Tel: 01-428 0088)

[]

Wholesaling Kesko Oy, the Finnish retailer-owned, wholesale corporation has placed an order for a Sperry Univac 1100/82 system. The primary applications for the system will be inventory control, order processing, warehouse operation, purchasing, statistical work and forecasting. A network of 16 Kesko branch offices with warehouse facilities are equipped with data terminals enabling them to communicate in real-time with the central computer complex. The communications network handles more than 110 000 transactions per day. The company carries a stock of more than 110000 individual items and handles over 2M order lines each month. As well as serving 3 500 stores of its own shareholders, the company also owns several department stores. Subsidiary companies operate a nationwide chain of petrol service stations and manufacture clothing, matches and bicycles. (Sperry Univac, Reming-

ton House, 65 Holborn Viaduct, London ECIP lAB, UK. Tel: 01-236 1010, Tx: 884403) []

Voice response system Golden Wonder Ltd, UK, are to install an MCS OVR-24 Voice Response System to speed up their sales force administration and order processing. The system will be switchable between two Data General Nova 2 minicomputers. These will be linked to another Nova 2 in each of a sister company's 13 UK depots where delivery notes will be printed out. Order input will also be transferred to files held on the company's 96k 1902T via a tapeto-tape link for inclusion in the production and stock-replenishment system. By equipping its sales force of 127 representatives and 35 telesales girls with voice-response terminals, the company hopes to speed up data capture, improve the accuracy of centrally held information, eliminate the cost of form filling and increase the amount of data fed into the system. It expects to be able to improve deliveries to customers from 72 to 48 h. The sales representatives on the road will be equipped with portable terminals that can be linked to any telephone with an acoustic coupler, while the talesales girls will have similar desk terminals. The MCS Voice Response System can support 24, 48 or 96 telephone lines. At Golden Wonder, 21 lines will be available. (MenziesCommunications

Systems L td, Princess House, High Street, Bagshot, Surrey GUI9 5AF~ UK. Tel." 0276 72523, Tx: 858304 []

Building society The Birmingham Building Society has installed an NCR 8450 Criterion computer and a minicomputer to act as an input device at its headquarters. VDUs have been installed at the head office to provide online enquiry facilities. It is planned to extend these to other head-office departments prior to developing a branch terminal network throughout the society's 31 branch offices. The computer is producing arrears reports with the appropriate letters, daily and monthly investors' balances reports by branch, management reports and statistics to be returned to the registrar. Those mortgage accounts handled at the moment by a bureau

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