Annals of Library SCience and Documentation 1991, 3B(1), 1-7

APPLICATION OF INFORMATION TECHNOWGYIN LIBRARIES

INTRODUCTION

Librarians are increasingly turning to informa-tion technology to automate a number offunctions in the libraries. A large number oflibraries in the world have automated one ormore of the following functions:

a) Acquisition,b) Serials control,c) Circulation,d) Cataloguing,e) Inter-library loan, etc.

For automating the above functions, informa-tion technology offers two approaches at thesystem level, i.e. integrated systems ap-proach, and distributed systems approach.

INTEGRATED SYSTEMS APPROACH

In the integrated systems approach, a singlesystem is used to implement automation in allthe functions or activities. This has the advan-tage that all the data files reside on a singlesystem, which facilitates easy flow ofinformation among various applications i.e.the automated functions of library. Data can beorganised efficiently reducing redundanciesto the minimum. However, the systems hassome drawbacks, i.e.

a) To keep all the applications on the samesystem, a heavy investment on a large con-figuration is required.

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Prof T. VISWANATHANDirectorINSDOC14, Satsang Vihar Marg ,New Delhi 110 067.

b) To give on-line support to a large numberof users, it requires a large disk storageand a powerful CPU to ensure reasonableresponse time for the users,

c) The system requires a mainframe com-puter which involves high initial invest-ment and

d) Failure of the system puts all applicationsout of gear.

DISTRIBUTED SYSTEM APPROACH

A distributed system approach permits incre-mental growth with low initial investment. Oneapplication at a time can be implemented anddedicated systems can be used for differentapplications. Different systems are intercon-nected to cooperate with each other. Multipleinterconnected systems provide backup capa-bility, i.e. if one system fails, another could beused to run the same application. Critical datamay be stored in more than one systems, thusproviding redundant copies of the data that maybe used in the event of a catastrophic failure.Distributed systems also permit the use ofcomputers purchased from different vendorsand thereby provides greater flexibility to theuser. In general, the distributed systems givean overall improved response and perform-ance.

The distributed systems are also not free fromdrawbacks. When multi-vendor systems areused, inter-system operability of hardwareand software is not guaranteed. Data storage

VISWANATHAN

formats in different systems may vary leadingto difficulties in excbange of data among them.The maintenance of integrity, security andprivacy are more difficult in the distributedsystem than in the centralised or an integratedsystem.

INFORMATION TECHNOLOGY ANDCOMPUTERS

For automating library functions, a variety ofcomputer systems and latest techniques ofinformation technology are used to a varyingdegree. They include:

-Personal computers-Mini computers-On-line systems-Large centralised terminal oriented

systems-Local area networks-W ide area networks-Puhlic switched telephone networks(PSTN)

-Satellite networks-Fibre optic transmission systems-Optical disk systems-Facsimile systems-Electronic imaging systems

Three approaches have emerged for the adop-tion of a software:

Development of an in-house applicationprogram,

Acquisition of a standard DBMS from. commercial sources and addition of an

application layer to suit the bibliographicappl ications.

Acquisition of a tailor-made bibliographicDBMS from commercial sources.

CONFIGURATIONS FOR LIBRARIES OFDIFFERENT SIZES

The extent to which information technology isapplied in a library depends largely on the sizeof the library. The number of holdings, thenumber of periodicals subscribed, the clienteleand the availabilityl non availability of on-line user services determine the computerconfigurations and the class and the numberof computer systems to be used. In cases whereon-line services are provided it is assumedthat the bibliographic information about docu-ments along with the keywords is maintained inthe computer. The first step in planning acomputer configuration for a library is tocategorize the status of a library as follows:

If H, P, C, S, represent the maximumnumber of holdings, maximum number ofperiodicals subscribed, maximum number ofregistered users, on-line user service support,and S 1 & S2 represent absence or presence ofon-line user services, respectively, a librarymay be categorized by means of a tuplecomprising four elements H,P,C,S as follows:

Very small library « 50,000, 100, 2000,S I);

Small library (1,50,000, 300, 3000, SI);

Medium Library(3,00,000, 500, 5000, S2);

Large library (5,00,000, 1000, 7000-, S2);

Very large library (>5,00,000,> 1000,>7000,S2);

While selecting the computer configurationsfor various categories of libraries, fourimportant parameters needed to be consideredare as follows:

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APPLICATION OF INFORMATION TECHNOLOGY IN LIBRARIES

a) Storage capacity;b) Processor speed;c) Software; andd) Networking capability.

Very Small libraryFor a very small library , two PCIXT systemswith the following specifications would suf-{ice.

- 8088 based CPU @ 8 or 10 MHz speed,- 640 KB main memory,- 40 MB Winchester disk,- 1 serial port and 1 parallel port,- BIW monitor,- MSDOS operating system,- CDS/ISIS or DBASE III plus software,- PC-to-PC communication software and- 132 Col. NLQ Printer.

Although one PC/XT will serve the purpose,it is desirable to have another PC/XT as astandby system. To get the best results, allthe updates must be carried out on both thesystems. In order to avoid the duplicate effortof inputting the information and the occur-rence of-possible inconsistency in data due totypographical errors, a simple PC-to_PCcommunication link may be established usingRS 232 Clinks.

To transfer files between the system, manylow cost software packages, such asKERMIT, MSNET, PROCOMM andCROSSTALK, are available . CDS/ISIS is agood choice to automate the library functionsalthough DBASE III with some programmingmay well serve the same purpose. DBASE IIIplus also supports network functions andwould enable file transfer between the twosystems.

Small Library

For a small library, a system configuration

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with two computers similar to that of a verysmall library is suitable. However, a morepowerful PC is required and aPC/AT with thefollowing specifications will serve the purpose.

- 80286 CPU @ 10 or 12 MHZ speed,- 1MB main memory,- 80 MB Winchester disk,- 1 serial and 1 parallel port,- BIW monitor,- l32 Col. NLQ printer,- MSDOS operating system,- CDS/ISIS or DBASE III plus software and- PC to PC communication software

Medium Size library

For medium size libraries with on-line accessfacilities, a larger computer system and a localarea networking environment are required.Users may access the database from a numberofterminals/PCs. Simultaneous operations ofcatalogue updating, inputting, issue/return,record and bibliographic search can take place.The larger computer system having a powerfulCPU may hold the complete database andprovide a good response time. A suitableconfiguration may be as follows:

- 80386 based CPU,- 4 MB main memory,- 160 MB Winchester disk,- Serial and parallel ports,- B/W monitor,- 132 Col. NLQ printer,- Unix operating systems and- A bibliographic DBMS or a relational

DBMS with a user written shell.- A Local Area Network (LAN) can be config-

ured in the library in one of the followingthree ways:

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1. Star configuration of LAN,

T = Terminal system

MAIN = Main system holding the database

2. Bus configuration of LAN

ITJ IT] tn

=rl/[MAIN ,

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APPLICATION OF INFORMATION TECHNOLOGY IN LffiRARIES

In a star LAN, the serial ports of the maincomputer system are connected to telephonelines through modems. Similarly, other accesssystems like PCs are also connected to thetelephone lines via modems. The PC can dial upthe number corresponding to the port of themain system and establish communication linkusing the PABX lines. This configuration iseconomical and does not call for special net-working interfaces and software. However,once a port of the main system is engagedfor a user, it is not available for other users.On the other hand, the bus and the ringconfigurations permit a large number of sys-tems to access the main system quasi-simultaneously. These configurations requirespeciaIised interfaces and software packages.These are generally suited for heavy trafficsituation and are recommended for large andvery large libraries.

3. Ring configuration of LAN.

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INTER LIBRARY NETWORK

For catalogue access and document inter-change among various libraries, inter librarynetwork is used with wide area communi-cation facilities. These may be:

- Public Switched Telephone Network (pSTN),- Public Data Networks (PDN),- Satellite Data Networks (SDN),- Network of Leased Lines and- Integrated Services Digital Network (ISDN).

PSTN works on the basis of circuit switching.In this case, the computers in two differentlibraries are connected to each other by a wirepath which is dedicated to these systems for theentire duration of communication. In this typeof switching systems, a call is set up, data istransferred and the call is released. It may benoted that once a call is set up, the line is held

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even though there is no data transfer using theline. PSTN, however, is the most easilyavailable form of communication that could beused for data transfer purposes.

Presently, many countries have set up dedi-cated public data networks (pD N) for datatransfer. These networks work on a packetswitched mode wherein a physical line can beused more efficiently by multiplexing mes-sage packets from a number of sources. Inpacket switched networks, the packets are movedfrom one station to another in hops and thus thenetwork functions in a store and forwardfashion.

Satellite networks are, in general, broadcastnetworks where a message transmitted by onestation is heard by all other stations.However, frequency division multiplexingand time division multiplexing techniques canbe used for providing point to point links insatellite networks. The main reason for this isthat a number of switching stations are in-volved in terrestrial connections whereas inthe case of satellite networks the only switch-ing station is the satellite itself. Satellite datanetworks may be single hop or two hopnetworks. In a single hop network, the ground

stations use larger antenna and powerfultransmitters and hence are more expensive. Ina two hop network, there is a large centralearth station and a small inexpensive userterminal. There can be no direct user to usercommunication in this case and all communi-cations have to be routed via the main earthstations.

ISD N is relativel y a new concept where a singlenetwork may be used for a number of serviceslike voice, data, facsimile and so on. Suchnetworks when realised will offer fairly inex-pensive mode of data transmission and docu-ment interchange.

FULL T.EXT STORAGE SYSTEM

Another important area of information technol-ogy that is likely to find extensive use inlibraries is the electronic imaging system.

These systems permit the storage of completedocuments including diagrams and graphs inelectronic media. With the use of opticalstorage devices, these systems are ideally suitedfor archival purposes. A block diagram depict-ing various components of an electronic imag-ing system is shown below:

SCANNER f-- DATA - DATA e---- OPTICALACQUISITION COMPRESSION STORAGE

I I I II I II

LASER PROCESSING MAGNETICf---SYSTEM

I---STORAGEPRINTER

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APPLICATION OF INFORMATION TECHNOLOGY IN LIBRARIES

FIBRE-OPTICS

Optical fibres are emerging as an alternativetransmission media to co-axial cables in tele-communication networks. There are three typesof optical fibres:

- Step index single mode- Graded index multi-mode- Step index multi-mode

Of these, the first one is the most expensivebut has a high bandwdth capacity. Thecommonly used fibres are graded index multi-mode type. Optical fibres have several advan-tages over the electrical cables but are notwithout problems. The merits of the opticalfibres stem from the fact that the basic materialused in their construction is non-metallic andelectrically non-conductive. The problems aredue to their delicate structure.

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CONCLUSION

The world is passing through an age of unprece-dented information explosion. As the timepasses, the librarians and information scien-tists will be called upon to handle, process andsupply larger and larger volumes of informa-tion. Recourse to automation and employmentof information technology is, thus, inevitable.However, the computer and communicationtechnology, itself, is passing through a periodof extreme evolution and development. In thetimes ahead, therefore, libraries and informa-tion centres will have to employ more andmore of modern information technology tocope with the rapidly multiplying literature andits demand allover the world.

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