CERN/FC/1374 CERN LIBRARIES, GENEVA Original: English 15 September, 1971

CM-P00087609

ORGANISATION EUROPÉENNE POUR LA RECHERCHE NUCLÉAIRE CERN EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH

FINANCE COMMITTEE

Hundred-and-fourteenth Meeting

Geneva - 29 September, 1971

ADJUDICATION FOR REMOTE INPUT OUTPUT STATIONS FOR

THE CERN CENTRAL SYSTEM

The document CERN/FC/1340, Programme for Acquisition of Peripheral Equipment for the CERN Central Computer System, outlines the programme of development needed to build up a decentralized service based on the CDC 7600 computer. The first step in this programme consists of the acquisition of five or six Remote Input Output Stations. Each station will be based on a small computer which initially drives a card reader, line printer and a communications controller. Additional stations may be purchased later and some will be expanded by the addition of extra peripherals and high speed communications equipment as the demands on the decentralized service grow.

The offers received from firms show the Modular One computer manufactured by Computer Technology Limited to be the one which most exactly meets the technical specification. The offer from Computer Technology Limited is a few percent more expensive than the two other possible machines for the initial configuration, but this is more than compensated for by the proven software and greater capability for ex• pansion of the Modular One Computer.

The Finance Committee is requested to approve the award of the contract for an initial order of five or six Remote Input Output Stations from Computer Technology Limited at a price of approx• imately 182,000 Swiss Francs per station (excluding the card reader), with the possibility of later

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I. INTRODUCTION

1. This adjudication is the first step in the program for aquisition of peripheral equipment for the CERN central computer system, described in broad terms in the Finance Committee paper CERN/FC/1340. Its purpose is to select equipment for a number of Remote Input Output Stations (RIOS) which are to form the first stage in the process of decentralizing access to the 6400/7600 computer (CERN/FC/1247).

II. SPECIFICATION OF THE RIOS SYSTEM

2. The development of the RIOS will proceed in two stages. In the first stage the RIOS will function in a manner simulating the performance of a CDC 200 User Terminal, i.e. as a simple remote station for reading cards and printing output produced by the central . This will enable the RIOS to be put into operation quickly with the 6400/7600 system, although initially the full speed potential of the stations will not be utilized. The second stage will involve a planned increase in the perfor• mance of the RIOS to allow them to operate at higher speeds and with a wider variety of peripheral equipment. This stage will require the development of a more advanced software (and possibly hardware) interface to the 6400/7600 system.

3. Initially it is planned to install five RIOS in Laboratory I, and probably one in Laboratory II to provide the 300 GEV project group with access to the central computer system. Later it is possible that additional simple stations will be installed, and that some special more powerful stations will be developed in experimental halls, or associated with special uses needing more powerful processing capacity and peripherals. About ten stations may finally be installed.

4. In the first stage each RIOS will consist of a small computer with 8000 words of core memory of at least 16 bits per word, and adequate processor and input-output capacity to support a line printer with a speed of either 300 or 600 lines per minute and a card reader with a minimum speed of 300 cards per minute. The station will be connected to the central system by a trans• mission line with a speed of 4800 bits per second, and provided with a teletype or typewriter as an operator control console. Software must be available to enable the RIOS to function in a manner exactly simulating a CDC 200 User Terminal so that no change will be needed to the standard CDC SCOPE to be used in the 6400/7600 machines. The RIOS equipment must be reliable and robust enough to be used by untrained operating staff, and must be capable of functioning with no special power supply or air conditioning requirements.

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5. The first RIOS must be available including all peripherals and the CDC 200 User Terminal simulator software, not later than February 1972 (i.e. just prior to delivery of the 6400/7600). Deliveries of later RIOS will be staged through the Spring and Summer of 1972 as the 6400/7600 takes over an increasing part of the CERN computer load.

6. For the second stage it must be possible to expand the RIOS in a number of ways as requirements for an extension of distributed computing facilities develop over the next few years. Particular requirements are: - The availability of additional peripheral equipment, notably additional printers per station, medium speed magnetic tapes, paper tape reader and punch, card punch units and plotters. - The availability of fast transmission line control• lers with a synchronous speed of at least 50,000 bits per second. - The capability of supporting a CERN developed transmission line controller with a speed of about 600,000 bits per second. - Input-output and processor capability to support an expanded peripheral configuration, and in particular to support simultaneously more than one line printer together with magnetic tapes and a high speed trans• mission line. Because CERN's requirements for expanded distributed access in the future are difficult to specify in detail at present, the flex• ibility and expandability of the equipment chosen are particularly important as criteria for selection.

III. THE TENDERING PROCEDURE

7. In order to survey the market end to gain information so as to be able to write a more realistic specification for the equipment, an initial call for tenders was sent on the 11th February 1971 to an extensive list of manufacturers, and 18 offers were received. After an analysis of these offers in the light of experience gained since March this year from the operation of two rented RIOS on the present central computer system, and following extensive discussions with manufacturers, a revised hardware and software specification, as outlined in section II above, was drawn up. This was sent to three manufacturers who then appeared capable of supplying the needed equipment at a reasonable price, asking for final offers.

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8. The first call for Tenders I-1133/DD Replies were received from the following, manufacturers among the list given in the Annex.

Manufacturer Offer based Nationality of on Computer mainframe manufacturer Electronics Associates Inc. (EAI) DCT 132 U.S.A. DATA 100 Model 78 U.S.A. Sprecher und Schuh Ferranti Argus 600 U.K. University Computer Corporation (UCC) COPE 38 U.S.A. Selenia GP 16 Italy Control Data Corp. (CDC) MSBT U.S.A. International Business Machines (IBM) IBM 1130 U.S.A. Telemecanique T 2000 France Philips I 880 Netherlands EMI PDI 11 U.S.A. Interdata Model 5 U.S.A. Varian 620 L U.S.A. Honeywell H 316 U.S.A. Tschäppeller 1200 U.S.A. Compagnie Internationale pour l'Informatique (CII) Mitra 15 France Digital Equipment Corp. (DLC) 11 U.S.A. Hewlett Packard (HP) HP 2100 U.S.A. Computer Technology Ltd. (CTL) Modular I U.K.

9. The replies were evaluated on the basis of the follow• ing criteria. - Price - Delivery delay - Capability of the basic RIOS, together with its potential for smooth expandability and flexibility in use - Availability of proven 200 User Terminal Software - Ability of the manufacturer to demonstrate the performance of the basic RIOS including peripherals 71/206/5/e CERN/FC/1374 Page 4

Using these criteria the RIOS offered were divided into four classes: (i) Machines whose high basic cost put them out of consideration. The tender replies indicated that it would be possible to fulfil our requirements at a price close to SFr. 200.000 per RIOS. (ii) Machines of low performance and little expandability, capable of simulating a 200 User Terminal, but with little or no potential for further development. (iii) Machines with good price and capacity, but lacking in one or other of the necessary attributes listed in Section II above. (iv) Machine which appeared capable of fulfilling our require• ments as posed initially.

10. Class (i) Proposals by the following manufacturers were eliminated on grounds of price. All quoted prices in excess of SFr. 260.000 for configurations equivalent to configuration II (see para. 15 below). a) IBM b) Philips ) Telemecanique d) EMI e) Interdata f) CDC

11. Class (ii) Machines offered by the following manufacturers were eliminated because they were basically too slow and too small to support efficiently the expanded peripheral configurations descri• bed in Section II para. 6. a) EAI b) SINTRA c) Ferranti d) Selenia e) Varian f) UCC

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12. Class (iii)

The following machines were eliminated because they failed to meet at least one important requirement of the tender specification.

a) Tschäppeller - The 1200 offered is a reasonably priced machine of good capability. However, the manufacturer was unable to offer us a fast (600 lines per minute) line printer and was also unable to make available a CDC 200 User Terminal Simulator.

b) Honeywell - The H 316 offered is a machine of good capability. However, a 200 User Terminal Simulator is not currently available on the machine, and Honeywell were unable to guarantee its availability within a reasonable time delay.

c) CII - CII offered a RIOS based on the MITRA 15. This is a recently developed computer of very interesting design and good capabilities and price. CII could not, however, meet the delivery delay re• quired and was also unable to provide a 200 User Terminal Simulator and a satisfactory line printer within a reasonable time.

13. Class (iv)

The remaining offers were those of CTL, DEC and Hewlett Packard. The second call for tenders was sent to these three Manufacturers.

14. The replies to the first call for tenders had indicated that it might be difficult to obtain a card reader that would satisfy fully CERN's requirements of strength and operability. The second request therefore contained a clause stating that CERN re• served the right to make its own arrangements concerning the supply of card readers.

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15. The second cell for tenders I-1133/II/DD The three manufacturers were asked to make offers for two configurations (described in section II), which differed only in the speed of the line printer. Configuration I includes a line printer with a speed of about 300 lines per minute, and configur• ation II includes a line printer with a speed of about 600 lines per minute. Details of the prices offered are as follows: Config• Manufacturer Computer Purchase 1st Year Subsequent uration Price Maintenance years SFr. SFr. SFr.

I DEC PDP 11 174,073 No charge 13,908 HP HP2100 176,828 9,720 14,448 CTL Mod. I 190,000 4,243 21,225 II DEC PDP 11 186,116 No charge 18,168 HP HP2100 183,627 9,960 14,940 CTL Mod. I 200,000 4,643 23,225

The prices above differ from those given by the manufacturers in the following respects: 1) The Hewlett Packard price includes the addition of a Direct Memory Access channel to make the machine more nearly comparable in performance to the others. 2) Hewlett Packard quoted a one time price of SFr. 13.200 for the CDC 200 User Terminal simulator. One sixth of this has been included in the price for each HP configuration. 3) The DEC offer has been modified by the replacement of an asynchronous line controller by a synchronous controller, necessary for 200 User Terminal simul• ation.

16. All manufacturers tendered as their two printers the Data Products model 2410 (Configuration I) and Data Products model 2440 (Configuration II). These printers have been evaluated by CERN and are considered satisfactory. Experience with the current RIOS operating in CERN has shown that a printing speed of 600 lines per minute is necessary in at least some of the sites to be serviced. This fact, together with the advantage of standardising on one printer and the small price difference, indicate that CERN should adopt Configuration II for all RIOS ordered.

17. All three offers meet the required delivery schedule. CERN/FC/1374 Page 7

10. The Hewlett Packard Tender HP have offered an RIOS based on the HP 2100 computer. This is a re-engineered and slightly faster version of the HP 2116 computer which has an internal design already many years old. The internal structure of the machine is old fashioned and lacking in flexibility. As card reader HP have offered the Documation , which is considered to be the most satisfactory reader of those offered.

19. HP have offered a CDC 200 User Terminal simulator based on one developed at the University of Bologna and adopted by HP as standard. HP have not, however, been able to make this package available to CERN for evaluation.

20. HP offer a wide range of additional peripherals, however from the point of view of expandability the HP 2100 is the worst of the three offers. The machine is above all limited because it has only two independent direct memory access channels, a fact which critically limits the input-output flexibility of the system. The card reader and printer interfaces offered can work either by interrupting the processor for each character of input-output or by direct memory access, but the limitation in direct memory access channels means that they would have to work by in any configuration containing high speed devices (e.g. tapes and fast transmission line). CERN has considerable experience in the use of the fully compatible HP 2116 computer for applications involving heavy input-output loads, and the somewhat dated input-output structure of the machine is known to place a severe restriction on the number of medium speed devices (e.g. printers and card readers) that may operate simultaneously in interrupt mode. This basic limitation in the input-output capacity of the HP 2100 makes it unsuitable for further consideration for the RIOS application.

21. The DUG Tender DEC have offered an RIOS based on the PDP 11 computer. This is a recent small computer of good internal structure, designed round a common bus used for all computer activity, inclu• ding memory access and input-output. As card reader DEC offer the Documation , which is not considered fully satisfactory because of the small input hopper and output stacker. DEC have indicated that this could be replaced by a more satisfactory reader at an as yet unspecified increase in price, or that they could supply a system without a card reader with a reduction in price of about SFr. 14,000 (estimate only) to allow CERN to replace the reader. A satisfactory replacement card reader would cost CERN about SFr. 12,000 leading to a configuration II price of about SFr. 184,000. More than 1000 PDP 11 computers have been delivered.

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22. DEC are the only manufacturer not to offer the CDC 200 User Terminal simulator as a standard software package. Such a package is known to be under development at the University of Texas. However this software is not yet available and we have not, therefore, been able to evaluate its performance. In addition DEC will take no responsibility for its installation and subsequent maintenance.

23. DEC also offer a wide range of additional peripherals. The expandability of the PDP 11 to handle a heavy input-output load at high performance is however, limited by the interfaces offered for the card reader and the line printer and the nature of the common bus used in the computer. The card reader and line printer both operate by interrupting the computer processor for each character of input-output performed, thus imposing a considerable load. The common bus structure limits the total input-output capacity of the system since all data interchange in the computer must use the same path. This is particularly restrictive when high speed peripherals (e.g. magnetic tapes and a high speed transmission line) operate at the same time as interrupting devices (e.g. card reader and line printer) and it imposes limits to the number of high performance peripherals which may be simultaneously serviced by the system.

24. The CTL Tender CTL have offered an RIOS based on their Modular I computer. This is a powerful small computer specifically designed for communications and time sharing applications. Its design is modular with a large number of independent data paths and a cons• equent hign total input-output capacity. The card reader offered is the Data Sciences 6002 card reader which is not fully satisfactory because of the small hopper and stacker capacities. CTL have however, confirmed that a system without a card reader could be supplied for a reduction in price of SFr. 18,000. CERN have already investigated a satisfactory replacement reader that could be installed for less than SFr. 12,000 using the CTL inter• face. This leads to a total price for CTL configuration II of less than SFr. 194,000. More than 100 Modular I computers are already installed in the field.

25. CTL are the only tenderer to have developed the CDC 200 User Terminal simulator themselves, and they offer it as a fully supported software product. This simulator is operational and has been demonstrated to CERN. It is considered to fulfil our requirements satisfactorily.

26. The range of additional peripherals offered by CTL is not as wide as DEC or HP but it includes all the items required by the tender request. The expandability and flexibility of the Modular I computer exceeds the DEC machine. The machine can be easily configured to include additional processors and considerable

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extra memory, and the high degree of independence of the data paths within the system makes its total input-output capacity completely satisfactory. In the configuration offered Modular I forms the smallest model in a range of satellite processors for large computer systems. The range is known as Satellite One and can be expanded by standard hardware and software increments to include support in an RIOS environment for more printers, paper tape equipment and magnetic tapes. The CTL printer inter• face also works in interrupt mode but CTL have indicated that a modification will become available to enable it to work without interrupting the processor. Their card reader interface works without interrupting the processor except at the end of each card.

IV. COMPARISON THE DEC AND CTL OFFERS 27. The comparitive prices of the DEC and CTL offers for configuration II including the card reader interface and system maintenance over three years, but not including the card reader are as follows DEC SFr. 208,452 CTL SFr. 233,093 The DEC price is based on a preliminary estimate from DEC that the price reduction in the case that CERN does not take the card reader offered, will amount to SFr. 14,000. A large part of the difference in price between the two offers is due to the difference in maintenance prices (see paragraph 15). The low maintenance price offered by DEC reflects the fact that DEC is already well established in Geneva. CTL on the other hand, do not presently have any installations in Geneva and consequently face high overheads in servicing the first computers in this area. CTL have, however, indicated that they would be prepared to negotiate a decrease in maintenance costs as a function of the number of systems ordered.

20. In comparing the two offers for technical merit for this application, two points are critical - The capacity of the equipment to support a wide range of peripherals in a flexible and efficient way. - The availability of proven software to enable CERN to offer an immediate trouble-free RIOS service when the CDC 7300/6400 system is installed.

23. Experience at CERN and elsewhere has shown that an RIOS system rapidly becomes the focus of computer activity in its neighbourhood. Computer users become used to having the RIOS facilities directly available to them and gradually demands for expansion of these facilities develop. It is already forseen that card punches, paper tape equipment, additional printers and magnetic tape units will be attached to different RIOS.

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requirements for expansion will certainly evolve with operational experience over the next few years, and thus the flexibility with which the basic RIOS can be configured to support additional peripherals is of great importance.

30. As noted above, there is a basic difference in the way in which the 11 and Modular I support peripheral devices. The FDF 11 uses a common bus (the Unibus) for all data transfer in the computer system. While capable of very high transfer rates if dedicated to one transfer only, the total transfer capacity of the Unibus drops sharply if a number of devices wish to share it by carrying out their transfers in an overlapped manner. this is the typical situation in an input-output system such as a RIOS and under these circumstancas each transfer on the Unibus (including processor references to memory) can be delayed for up to 3.5 microseconds despite the fact that the 11 memory offered has a cycle time of 950 nanoseconds. The Modular I on the other hand offers a choice of a number of ways of carrying out transfers between a peripheral device and memory. Each memory module in a Modular I system has a minimum of 4 independent access paths, one of Which is dedicated to the processor. Slow peripheral devices may operate by interrupting the processor to make it carry out the memory transfer. Medium speed devices (e.g. card reader) may suspend the processor and use the processors path to memory to carry out a memory access in less than 3 microseconds without actually interrupting the current processor program. High speed devices (e.g. tapes, fast transmission lines) may use their own direct access path to the memory completely independently of the processor, taking only one memory cycle (1.5 microseconds for thc memory offered) for each word transferred. This choice of data paths within the system offers an extremely high degree of flexibility in connect• ing peripheral devices efficiently in a way that is suited to their characteristics.

31. The attachment of a number of non-CDC RIOS to the CDC 7600/6400 system is likely to cause a number of operational problems. Locating responsibility for possible malfunctions in the RIOS service and correcting the errors, require confidence and goodwill on the part of CDC, the RIOS manufacturer and CERN. wish to reduce these problems by choosing an RIOS manufacturer with experience in the installation and support of CDC 200 User Terminal simulators, so as to ensure the smoothest possible introduction of the RIOS service. CTL is the only manufacturer who fulfils this requirement by offering a fully supported software package, as well as having satisfactory operational experience in providing RIOS for CDC 6000 installations.

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32. It is therefore apparent that while the offers of both DEC and CTL satisfy the minimum requirements of the request for tender, the CTL Modular I computer offers by far the greatest flexibility for future expansion, and at the same time only CTL offer a fully supported CDC 200 User Terminal simulator, together with first hand field experience in installing it. These factors more than justify the price difference between the and the DEC offers.

V. RECOMMENDATION 33. The finance Committee is therefore requested to approve the award of the contract for the standard Remote Input Output Station for the CDC 6400/7600 computer system to CTL at a purcnase price of approximately SFr. 182,000 per station (excluding the card reader) for an initial order of five or six stations with the possibility of purchasing further stations and additional equipment at a later date. The cost of the initial order will then be approximately SFr. 310,000 or SPr. 1,092,00. The recommendation is made subject to the satisfactory conclusion of negotiations with CTL on maintenance and other costs.

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