telecommunications options connect oclc and libraries to the future
TRANSCRIPT
This article was downloaded by: [Cornell University Library]On: 14 November 2014, At: 20:29Publisher: RoutledgeInforma Ltd Registered in England and Wales Registered Number: 1072954Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH,UK
Journal of LibraryAdministrationPublication details, including instructions forauthors and subscription information:http://www.tandfonline.com/loi/wjla20
Telecommunications OptionsConnect OCLC and Libraries tothe FutureMarshall Breeding a aa Vanderbilt University , USAPublished online: 17 Oct 2008.
To cite this article: Marshall Breeding (1998) Telecommunications Options ConnectOCLC and Libraries to the Future, Journal of Library Administration, 25:2-3, 111-128,DOI: 10.1300/J111v25n02_12
To link to this article: http://dx.doi.org/10.1300/J111v25n02_12
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all theinformation (the “Content”) contained in the publications on our platform.However, Taylor & Francis, our agents, and our licensors make norepresentations or warranties whatsoever as to the accuracy, completeness,or suitability for any purpose of the Content. Any opinions and viewsexpressed in this publication are the opinions and views of the authors, andare not the views of or endorsed by Taylor & Francis. The accuracy of theContent should not be relied upon and should be independently verified withprimary sources of information. Taylor and Francis shall not be liable for anylosses, actions, claims, proceedings, demands, costs, expenses, damages,and other liabilities whatsoever or howsoever caused arising directly orindirectly in connection with, in relation to or arising out of the use of theContent.
This article may be used for research, teaching, and private study purposes.Any substantial or systematic reproduction, redistribution, reselling, loan,
sub-licensing, systematic supply, or distribution in any form to anyone isexpressly forbidden. Terms & Conditions of access and use can be found athttp://www.tandfonline.com/page/terms-and-conditions
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
Telecommunications Options Connect OCLC and Libraries
to the Future: The Co-Evolution
of OCLC Connectivity Options and the Library Computing Environment
Marshall Breeding
The succcss and sustained growl11 of OCLC rcl'lccts the v : l l l~e nl' OCLC's syslcms and scrviccs l o libraries. OCLC's t rn l i~ l c prvclucts s ~ ~ c l i ;IS
Wc~rlclCat (thc O C L C Onl ine U n i o ~ ~ Catalog) tlic I~ i t c r l i h ra ry Loan syslcm. and tl ic OCI-C FirstScarcli service have al l proven I l ie~nsc lvcs ;IS v : ~ l u : ~ h l c rcsoul-ces. T l ic succcss o f these resc>urces t11 a large eslcnt can he a l l r ihu lcd lo the cffcct ivenrss 01' Ihc mclhucls l l int O C L C proviclcs f ~ ~ r accessing its c ~ n l i l ~ c svstc~i is. I ts systcms wou ld he o f l i l l l c v;tluc i f l i l i rar ics lackccl :IL~CLIII;IIC ;~cccss ~ i i c c l i : ~ ~ i i s n i s .
1 have Iic;lrd O C L C s la l l say many t inics that the org:~nizaI inn's c e n t r ~ ~ l ILicus h:~s always h e n on t l i r c ~ i n t c n t ul ' its systcnis and scrviccs. Tclccom- n ~ ~ ~ n i c n t i n ~ i s has ncvcr hccn n gonl i n itself, hut ;I ncccssary endeavor in
Marsli;~ll Breeding is Lihrary Nelworks a d Micrucun~pulcr A ~ i : ~ l y % l . Vailder- hi l l U~iiversily.
8 1998 liy Tlic H;~wortl i Press. IIIC. A l l ~riglils reserved. 1 1 1
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
112 OCLC 1967-1997: Thirty Years of Furhering Access lo fhe World's Infor~nalion
which it must cngagc to support its primary intcrcsts. I n this articlc, wc explore the methods that OCLC has implemented over the course of time to make its services available to its member libraries. These access meth- ods have evolved to keep pace with changes in the library computing environment.
At the time that OCLC began expanding its user base in the early 1970s, libraries lacked both the equipment to acccss such a system and the in-house technical expertise to install, configure and maintain complex telecommunications equipment. OCLC was extremely successful in treat- ing access methods that could be managed under these conditions. Somc of the characteristics o f the network that OCLC constructed to meet the needs of this earlier library environment include:
A l l equipment is provided by OCLC. Communications lines and all telecommunications equipment are installed by OCLC's designated agents. End-to-end support is provided from OCLC. Built-in diagnostics can isolate almost a l l error possibilities. Hardware is maintained by OCLC via its service agents. OCLC equipment does not interact with other systems except for record transfer. Proprietary networks and communications protocols.
Considcrablc timc has clapscd since OCLC's beginnings. The computer and telecommunications industry has changed dramatically and the typical library computing environment'has evolv& accordingly. Today, th; typi- cal OCLC member library employs computers and networks and is involvcd with various types o f automation prqjects and subscribes to a variety of electronic information resources. OCLC is but one of these resources and OCLC's role is to integrate their services into the library's computing environment. I n contrast to the earlier model where OCLC assumed complete control and responsibility, a morc modcrn approach might include these characteristics:
Most computers that access OCLC are owned and maintained by the library. The library assumcs morc responsibility in providing support for its own conimunications environment, and OCLC services are but onc feature of that environment. OCLC provides support only to the point at which it connects to thc
library's network. Failures within the library's network cannot be detected or corrcctcd by OCLC.
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
I> ihrary maintains its o w n c o m p ~ ~ t e r and nc lwork Ii;~rclwarc. O C L C ' s scrviccs arc h igh l y intcgratct l w i t h l ih r ;~ry 's nctwtrrks O C L C fo l l ows industry-stantlard ne twork ing mclliircls.
T l i c la l tcr :~pproac l i ~ ~ l t i m a t c l y ol'fers ;I lihr;wy more I ' l c s i l ~ i l i t y u ic l cont ro l i n t l ic way i t uses OCILC's scrviccs. L ibrar ies that l i ;~vc aclceluatc t c c l i n i c i resources can take advant:~gc of O C L C ' s l i cwc r :~cccss opt ions ;IS
p:ut o f ;I more general goal v f c lcvcloping an cnr ic l ied inl 'ormation cnv i - ronmcnt . Fo r l ihrar ics w i t h more ~nicrtlest in-house ctrmputcr cspcrtisc, O C L C w i l l cunt inuc 11) o f i c r its earl ier more controllccl c r~v i remnicnt 1;,r scmc t imc.
I n order l o pruv idc I i ig l i l y rc l iah lc acccss to i ts scrviccs. O C L C clcvcl- opeel anel clcployccl an i nc l~~s t r i i ~ l - s t reng t l i t c l c c o m ~ n ~ ~ ~ ~ i c : ~ t i o n s network . F rom the t imc that O C L C I lcgan expanding its mcmhcrsh ip i n t l ic early 1970s. i ts network g rew accordingly. T h i s network wxtl ilcclicatccl tc lc- c w i m u n i c a t i o n s c i rcu i ls and propr ietary communicat ic ins p ro t i~cc~ ls . I n 1'491, O C L C rcpl:~cccl th is network w i t h a tv ta l ly ~ i e w one hascd o n X.25 packet sw i t c l i i ng tccl inology, 1rep1-cscnting :r $70 m i l l i o n i nvcs t~ i i cn t . T o d i ~ y . O C L C is ill tl ic c ;~r ly st:~gcs o f inst;dling :I new nctwcrrk hasctl on framc relay tc lccommunica l ions imd T C P I I P protuculs.
THE EVOLUTION OF OC1.C 'S ACCESS METHODS
W h e n O C L C Ihcgan dep loy ing its services. l i h r x i c s wc rc I :~rgc ly not a~~rorn ;~ tcc l . For many l ihrarics, O C L C tcrni i r i :~ ls wcrc thcir first computer cqu ipmcnt . %clay, most l ihrar ics arc steeped i n : ~ ~ ~ t c ) m a t i o n . l ' l ~ c y clpcratc l ih rary automation systems, prov ide acccss for their c l ients t o the Inlernct. run C D - R O M networks, as w e l l ;IS many o l l i c ~ . cnmp~~tcr -hasee l systems. Less u t ' t c~ i t lvcs ~ l i c l ihrary ncct l OCLC t o provielc works ta t io~rs ant1 cncl- to-end cc~nncct iv i ty, hu t r ;~t l icr t o intcgratc its scrviccs i n to an ex is t ing I i l m r y compu t ing envircrnment.
O C L C is c~rnstant ly cI1;rllcngcd to k r c p i ts t c l c c o m m u n i c a l i ~ ~ n s ~ i i c t l i - crcls and opt ions i n stcp w i t h the practices of' the data communic;~ticrns inelustry and w i t h t l ic computer dcp leymcn t trcncls in t l ic typical l ihrary. A s sl;incI;~rcls cmcrgcrl, OC1.C I h s reshaped its t r l c c t r ~ i ~ ~ i i ~ ~ ~ i i c : ~ t i o ~ i s nc l - w ~ k round those s t ~ ~ n d a r d s . W h i l e O C L C ' s ur ig ina l acccss metliocls were c l~ rsed ;III~ prnprictary, i t I ias m o v e d t n w ; ~ r d the use ell' st;~ncl;~rcl nctwcrrk tccl inolngics.
O C L C ' s acccss rncl l iods must acco~nrnoda t r a wiclc r:lngc of lil-rrary types. Whcthcr the l ib rary I ic very large 01- very smal l . wl iet l icr h e l ih rary lh;~vc une ccrmputcr o r Iiunclrcds. OCLC m l ~ s l e>ffcr ;I mcthocl t'rrr ;~cccss
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
114 OCLC 1967-1997: Tlrirly Years of Furfl~ering Access to the WorldS Itzfortnufiotr
compatible with its computing infrastructure, technical ability and fiscal means.
OCLC's telecommunications methods have evolved from a completely proprietary, self-contained network, where OCLC provided all equipment, to one that cmbraccs local area network technologies and library-owned computer equipment. In the following section, I wil l examine how OCLC's access methods have evolved to accommodate changes in the library cnvironmcnt.
The Terminal-Based Environment
A look at OCLC's original environment puts the current environment into perspective. When WorldCat was started in 1971, it operated from a single Sigma 5 mainframe computer. OCLC's earliest network was based on static tclccommunications links and data terminals. The original tele- communications network consisted o f dedicatcd circuits bctwccn thc host computers at OCLC in Columbus, Ohio, and each library. The earliest mcthod tor accessing WorldCat involved the use of daisy-chained termi- nals. Thc MlOO block-mode terminal was introduced in 1973 and the M 105 succeeded it in 1978. These terminals provided access to WorldCat, allowed the transfcr o f MARC records to local systems through an asynch- ronous scrial port, and records could be printed on a serial printer. During this era, a common arrangement was for the library to pair an OCLC tcrrninal with a tcrminal from its local system to transber cataloging records. (An carly OCLC tcrminal is on display in the Smithsonian Institu- t i on Museum of American History, Information Age exhibit.)
These terminals communicated with OCLC's host computers through syn- chronous serial communications, using the proprietary "OCLC Library Linking Protocol." Synchronous cornrnunicntions involves an electronic clock pulse that controls the communications stream. The clock synchro- nizes the data communications process. The beginning and end of each data clcmcnt is dcfincd by its rclation to thc clock pulsc. This contrasts with asynchronous communications, that uses no clock signal. With asynchronous communications, timing is not so critical. Stop bits and start bits dcfinc each data clcmcnt, and thc spccd of the data transmission can be flexible. The synchronous communications used by OCLC relies on a polling process where each terminal in a group communicates with the host computer in turn.
The telecommunications lmks that connected libraries to OCLC's net- work were called multidrop lines. Originally 2400 bps, these links are now 9600 bps lcascd lincs, providcd by a long distancc carrier. The multidrop linc tcrminatcs in thc library with a synchronous modem which in turn
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
crilinccts lo a chain ot'synclircrnc~us devices. such as Icl-nlin;lls. The early network used AI&T data circuits and P;~raclync modems whilc O(:I.C's current network llses Sprint matlcms and clata circuits. Each multitll-q-, l inc can support up to 1.5 tlcviccs. Mul t ip lc m ~ ~ l l i d r o p lines ;IIK inst;~llccl in l i l~raries th;~t rccluirc larger numhel-s o f O C L C tcrminals. O C L C aswsscs a nionlhly network access cli:~rgc thr cc;~cli n i ~ ~ l t i d r i q ~ linc inst;~llctl in ;I lihrary.
Access Tlrrorrgh ~Microconryrrters
Data terminals such as tlie M I 0 0 and M 105 arc inherently singlc-pur- pose tlcviccs. l'licsc terminals wcrc largc and unruly clcviccs. anel i t t c rd two il l ' them to perform basic cataloging operations-hotli an O C L C I c r~ i i i - nal :mJ ;I local system terminal. Tlic limitations o f terminals cvcntually hccamc more apparent. As more programmable devices cmcrgctl. the Iahcl '.clurnh terminal" was appropriately applied l o these devices.
The micrucompulcr revolution hcgnn in IOSI with the in t ro t luc t i~~n of tlic [BM PC. I t was this system that I'irst made microcomputer tccl inolt~gy ;~cccssihlc to the husiness market. Earlier niicrocwnputcrs were sccn as cspcrimcrital and mostly appropriate for Iiohhyists. But this microciim- puler was dcvclcipcd and supported hy tlie samc company that Iiacl clcliv- crccl large mainframe systems since the carlicst clays o f ciimputing. Mxny Ihclicvccl th:~t n i icrocomp~~tcrs would br ing r;~dic;~l cli;~nges l o the h~~s incss cc~niputing cnvironrncnt.
The I B M PC. I i iwcvcr. lackccl tlic ahili ly tu cummunicatc directly on thc OCLC: netwol-k since its communications opt io~is inc l~~t lcc l only ;~sy~~c l i ronous scri:~l ports and p;~r;~l lcl ports. Adtlit innal li;~rcl\varc ant1 sol'twarc would he needed to use PCs wi th the OCI .C nctwc~rk.
111 1984. O C L C intrcducctl the M 3 0 0 workstalion. This was h;~sically ;in I B M PC cquippetl with n syncl ironnm communic;~tions ailaplcr. OCLC clcvclopcd terminal emulation software for the MXIo t l l :~ t ;1l111wccl i t to access WorltlCat in m ~ ~ c l i the samc way as the M I 0 5 tcrmin:~l. 'l'lic hcy- hn;~rt l I ;~yout o f the PC differed in many ways from the M 105 tcr-minal. hut the sol'twarc rcmappctl the keys. Bihliogr;~pliic records COLII~I he tr;ms- fc r rc~ l to a local system via tllc PC's I ~ i ~ i l t - i n ;~syr~chrimous scri;~l purl. Printing operated through st;~ntl:~rd p a r ~ ~ l l e l printers. w l ~ i c l i wcrc rn~1c.11 rnvrc popular than Ilie serial printers required hy the M I l l5 terminals.
Over time PCs c m c into general ~ ~ s c in lihrarics, :~nd it hccamc tlcsir- ;1l1le for t l i cn~ to he ahlc to use tlicir own ccluipnicnt. The purchase arid support c r f OCLC-supplicd equipment was a I'iriancial hurtlcn 1 ; ~ m;my lihrarics. Uut the rccluir-emcnt for tlie synchl-uncius cummi~~ i ica t ions acl:~pter severely li:~n~pcrccl tlie :lhility l o intcgratc PCs into the 0Cf.C
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
116 OCLC 1967-1997: TI~irly Eurs of Furthering Access to the Worldh I~t/ormutio~z
network. The synchronous adaptcr was sensitive to timing issues and required hardware interrupts and an inputloutput address. These factors led OCLC to allow only M300 Workstations on its network and not allow library-supplicd computers to bc cquipped with these adapters and con- nected to the nctwork.
The M300 was but the first microcomputer-based access station offered by OCLC. This original device was based on the 8-bit Intel 8088 micro- processor. As this microcomputer family evolved, OCLC's workstations have kepl pace. OCLC has offcrcd workstations based on each of the Intel processors: the 8088, thc 80286, the 80386, the 486, and the Pentium.
OCLC Cornnuinications Controller: Native Access for PC-Based Workstations
In 1988, OCLC introduced the Communications Controller, which allowed up to eight devices to access OCLC through asynchronous serial communications. This meant that PCs could access OCLC through their native serial ports without the use o f an asynchronous adapter. For the first time, libraries could use a generic PC as a dedicated computer on OCLC's network without any special hardware. OCLC assesses the same monthly communications charge for each active port of a Communications Con- troller as i t does for a dedicated terminal.
The communications controller itself was a PC with an asynchronous communications adapter and a multi-port asynchronous adaptcr. I t ran soh- ware that controlled the tlow of data from each of the devices attached to the asynchronous ports to the synchronous network. Through its own syn- chronous adapter, the Communications Conlroller connects to a multidrop line. Figure 1 illuslrates a Communications Controller on a multidrop line.
Thc Communications Controller provided access for a variety o f asynch- ronous devices. In addition to OCLC's own microcomputer workstations, libraries could connect their own microcomputers, saving the additional expense and maintenance costs associated with OCLC-supplied equip- ment. Increasingly, libraries are used to providing thcir own support for microcomputers and want the flexibility of doing so for OCLC access stations. The Communications Controller also supported asynchronous ASCII terminals. These devices had somewhat limited functionality, but were very economical.
Nehvork Access to OCLC Through the Communications Controller
While the Communications Controller was dcsigned to provide dedi- cated access to microcomputer workstations, there are a number of ways
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
The Cataloger's Workstation and OCLC Services
One of the models for providing a computer environment for technical processing is the "cataloger's workstation." Such a computer environment would include access to all the systems, services. and information tools rewired to oerform technical services'tasks. Some of the systems included on a cataloger's workstation would be access to the library's local online sys- tem, access to OCLC and other bibliographic resources, access to Internet-based services, and information resources such as the Cataloger's Desktop software from Library of Con- gress. The general principle of the cataloger's workstation is that all these resources be available to each person's individual computer rather than having staff go to other computers to get access. For OCLC Cataloging, the traditional access method involved was having a set of dedicated computers that techni- cal services staff all share. This arrangement usually meant that staff had to take turns doing OCLC work and had to use this resource according to a set schedule. In a cataloger's workstation environment, access to OCLC would be available at any time, though it would be expected that each person would use these resources judiciously. The cataloger's workstation involves providing part-time access to a large number of com- puters rather than providing full-time access to a smaller num- ber of shared stations.
The key to the implementation of the cataloger's workstation involves providing access to all the various resources through a local area network. Three different methods can be used to provide access to OCLC services through a LAN. These include network gateways to the OCLC Communications Controller, the OCLC's Telecommunications Linking Program, and the Dedi- cated TCPIlP Access to OCLC.
to provitlc :I more cost-cffectivc distrihutcd ;~cccss to O C K using this clcvicc. Thc trailiticmal co~lfiguraticln irlvolvcs a cahlc that cvnnccls the scri;~l port ol' tlic PC will1 onc of the asy~~cllro~ic~us purts ol' tlic CCIIIIIIILI- ~ i ic i~t io~is Controllcr. l'hcrc is a one-to-one relationship hccwccn the 11um- Iw of computers tIi;11 can acccss OCLC anil the numhcr ol'activc pcrrts on tlic Communications Controllcr. Wliilc this cvnl' ig~~ralio~~ is wcll suited I. t~r creating tletlic;~tcrl :~cccss st:~tions tli;~t can he sh:~rcd Ihy ;I numhcr i r l users.
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
118 OCLC 1967-1997: Thirty Years of Furthering Access to the World's It~fort~tatiotz
FIGURE 1
Multldrop Llne
Sprlnt Modem
i t is not conducive for providing part-time access to OCLC to a larger number of computers, following the Cataloger's Workstation model, for examplc. Whilc i t would bc possible to string serial cables to each PC to provide part-time access and pay for an active Communications Controllcr port, this would not be a financially efficicnt model. Given the monthly charges associated with each active port on a Communications Controller, libraries must do al l thcy can to maximize their use. The economic factor o f maximizing use of OCLC ports, the desire to provide access to the largest numbcr of computers possible, as well as the deployment of local area networks within libraries, led to the development o f mcthods to integrate Communications Controllers into the network environment.
One of the earliest methods that emerged to distribute the use of Com- munications Controllcr ports involved terminal servers. With this model, each active port o l thc Communications Controller was connected to a port on a terminal server. The terminal server was then configurcd to offer the data on the port as a service to other deviccs on the network. Likewise each computer in the library that was to providc access to OCLC had a cable that attached its scrial port to a terminal server. When one o f these computers needed to access OCLC, it would issuc thc commands to request the service, and a virtual connection would be established between this PC and one of the Communications Controller ports, if there was one available. This arrangcmcnt allowed a much greater number o f computers in thc library to have potential access to OCLC than there werc active Communications Controller ports. Thc number of simultaneous sessions was limited by the number o f active Communications Controller ports. Depending on the workflow patterns o f the library, cach port could support from 2-4 actual uscrs. Libraries might still choose to dedicate some ports
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
to ful l - t ime use to acconimtrtl:~te special ~ ieet ls sucli as intcr l ihr;~ry lo;111 ol f iccs, antl other situations that ilsc O C L C conl inucr~~s ly .
T l i c use of terminal scrvcrs t v clislril?ule acccss I t ) lhc C o ~ n m r ~ n i c ; ~ l i o l i s C o n l r d l c r predated O C L C oi'l'icial support l o ne lwork ;ICC~SS ~ i i e t l i ~ d s . ILiIirarics implemented these arrangements at t l ic i r nuin risk. k n o w i n g that O C L C ' s support gocs on ly :IS Far ;IS the C:onirnunic;~lions Control ler. A n y I ~ i l u r c s uf the terminal scrvcrs. niicrocomputers. o r any crllicr part of the c n v i r ~ i n m c n t were tl ic rcsponsihi l i ly o f the l i l m r y .
Vunderhilt Un ivers i ty implcmentccl this type o f O C L C acccss Ihegin- n i n g :11xiut 1988. N o t on ly wcrc w e at Vandcrhi l t able l o ga in c l i s l ~ ~ i l w k c l ;~cccss t t ~ O C L C t h r o i ~ g l ~ l l lc Ic rmina l scrvcr arrangement, w e wcrc ;~ l s t i ahlc to cuml i inc access to O C L C and our N O T I S syslcm I l l rough a single m ic rocon ipuk r . Ihd:~!. i t is cxpcctcd that computer ~ ~ s c r s w i l l acccss m u - t ip lc systcnis tl i trugli mul t i task ing cnvironrncnls such as Winc l (ws. But in Ihc D O S environment. this was not a t r iv ia l ; ~ c c ~ r ~ i i l i l i s l ~ ~ n e ~ i t . We con- nected tl ie ports o f an I B M 7 17 1 asynclirtmous prc~t i rcol cirnvcrtcr to the same typc of tcrminal scrvcrs so that l ihrary stalions c o ~ ~ l c l ;~lstr i~cccss NOTIS . We i11so :~ l t :~c l ic r l c;lcIi o f the t w o serial ports ol' t l ~ c PC I t r I c rm in ;~ l scrvcrs. so that one cou ld connect l o O C L C and tl ic c~t l icr tu NO'TIS. A c o n ~ n i ~ ~ n i c a t i u n s package (M i r ro r f rom SofIclone, Inc.) proviclctl hu111 !lie terminal emulation and tlie task-switching environment. Th is soI'tw;~rc ;1l111wcd i tsc l f and onc o l l ic r prugram to operate i n t l ~ c computcr 's mcmol-y at (l ie same time. T h c user wou ld press the tlcsignated hat key io lo& hetwccn the t w o programs. A NO' I ' IS session w v u l i l apcralc i n l l ic mi l in communic ;~ l ions program, antl the O C L C tcrminal scrl'twarc w : ~ s Itrailctl as tlic scconcl;~ry application. The user coulcl instantly Iogglc I x t w c c n OCIX ancl N O T I S o n the scrccn w i t h a s inglc key prcss. We also ;lclclccl ;I th i rd scrial port t v the I'C MI that records c o ~ ~ l d Ihe exported l o N O T I S t l l ruugl l their Gcncr ic Transl'cr and Ovcr lny (GTO) g:~tcw;~y. W h i l e this was n vcry cumhcrsome arr;~ngcn~cnt i n many ways, i t provct l at the l i m e to hc a vcry effect ive means to creat ing a mu l t i -p i~ rposc technical services workst ;~ t ion. Th is wriul t l not havc hccn an al'forclahle venture w i l l i ou t the comp~,nrnt h a t n l l owcd LIS to share :11ic1 t l istrihutc tl ic use o I ' c ;~c l i O C L C Ccmrn~~nic :c- t ions Contr i r l lcr port. '
O C L C ;~lscr dcvcl<ipct l methods h y w l i i c l i lihr:ll-ics cou ld integrate O C L C Cornmun ica t i c~~ ls Control lers in to their n c t w ~ d s . W h i l e tcl-minal scrvcrs o f fer scrnic capahil it ics I h r accessing d i n e syslcms. l oc :~ l arcs ncttvorks ( L A N s ) arc far more c f f i c i c ~ ~ l and po\vcrl'ul rcsourcc s l i :~r ing cnvirunments. I n ;I LAN. each microcomputer is equipped w i th :I nctwcrl-k intcrl'acc card (N IC) . usually c i t l icr an Ethcrncl o r Token R i n g card. ' l ' l~ rougl i th is one network connection. n I:lrge v : ~ r i c ~ y o f services c:ln he
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
120 OCLC 1967-1997: Thirty Years of Furthering Access to t/le World's It$ormatiorl
provided to the computer. Disk storage on a file server, access to shared printers, electronic mail, and access to various onlinc systems are typically available on a LAN . I n a library environment, one of the desirable options on a LAN would involve access to OCLC.
The Communications Controller can bc integrated into a LAN to pro- vide OCLC services to networked library computers. Therc are a number o f dil'fcrcnt types o f communications servers and gateways that can be connected to the asynchronous port of the OCLC Communications Con- troller to provide network access to OCLC. The main problem, however, lies in gctting the lcrminal software to expect the OCLCsession to operatc from the computer's nctwork card rather than from the asynchronous serial port. This problem was solved in 1992 when OCLC released Version 2 of Passport software which included support for a set o f network drivers. The L A N drivers provided with Passport included those for Novell Asynchronous Server Interface/Novell Asynchronous Communication Server (NASIINACS), NetBIOS, TCPIIP, and one for a generic one for BIOS Intcrrupt 14.
Providing L A N access to the Communications Controller through this approach involves creating an asynchronous gateway on the network and latching up its ports to those on the OCLC Communications Controller. For those with NetWare networks, Novell offered a product called thc Novcll Asynchronous Communication Server (NACS). This software ran in a computer that had a network card and a multi-serial port adapter. Each NACS port connects to an OCLC Communications Controller port. To acccss OCLC in this environment, Passport is configured with the Novell Asynchronous Interface (NASI) L A N driver. This environment allows a much larger number of library computers to have part-time access to OCLC. The numbcr o f active Communication Controller/NACS ports limits the numbcr of computers that can access OCLC simultaneously. Details on the implementation of this model of access can be scen in Breeding (1992)."or those with TCPIIP networks, a terminal scrver can be used in place o f the NACS. For acccss in this environment, Passport would be configured to use the TCP/IP LAN driver. Figure 2 illustrates how the Conimunications Controller can be integrated into a TCPIIP net- work through a terminal server. LAN access to OCLC was originally developed for the DOS version of Passport and this capability continues to be part of Passport for Windows.
At Vanderbilt University, we implemented networked access to OCLC through a set of NACS after a L A N was implemented in the library to replace the earlier terminal servcr environment.
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
FIGURE 2
Network Gateway PCs connected to Network w~th OCLC Passport Software and LAN drtvers
L~brary
configured to offer each asynchronous port as a network service
INTERNET ACCESS
Since 1995. O C L C has offcrccl acccss to it, catalonine and resource -. " s l im ing services via I l i c Inlernet. T h i s access mcthocl wits cs tah l is l ic~ l al'ler a succcssl'itl 9-nicinth trial. I'or many l ihrarics. this :tppro;rcli : ~ l l o w s them to t:~kc aclv;~ntagc o f their cx is t ing It itcrtiet contiectic~ri to r cp l i~ce o r supple- ment o l l i c r access mctlinds. To acccss the OCLC sy*tctl i v i ; ~ l l i c Internel, lihr;try computers n ius l conncc l to a local ;trc;i nc lwnrk Ilia1 supports I 'CPI IP protocols and use Passport I b r W i t i ~ l o w s w i t h i ts hu i l t - i n T C P I I P clrivcrs. Thc computer must :llso l iavc installed a I C P I I P nc twork stack that is W i n s c ~ c k - c u m p l i ~ ~ t i t . T l i i s is the same nc twork scrfw;lrc I-ecl~tircd 11,
support the Nctscape Nnvigalcrr, M ic roso f t Internet Exp lorer and othcr w c h browsers, s o most computcrs arc l i ke l y to h c properly cclitippcd. T l ~ c l ihrary's nc twork rnitst connect to the Internet, either t l ircclly, o r v ia ;I ci lmpus o r ccrrporote n r l w o r k .
Connect ing l o I l ie OCLC system v i :~ the In lc rnct dcrch 1101 e l imina le c o m m ~ t n i c a t i o n chargcs. OCLC asscssrs a per-minute conncclicm fcc l o r Cata log ing atid Rcsvurcc Sharing over t l ic Inlcrnct. For libraries w i t h r x t cns i ve OCLC acccss needs. i t may h c cost-cl'l'cctivc to use c~thcr con- nect iv i ty methods.
'l'lre ma in dr;iwhack o f Internet :~cccss to O C L C services invo lves pcr -
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
7 22 OCLC 1967-1 997: Tltirty Years of Furfllerit~g Access to the World's I~lforntation
formance and reliability. OCLC built its private network to be extremely reliable and to offer consistent performance levels. The infrastructure o f its network is well-balanced with thc numbcr of actual users. OCLC main- tains over a 99.8 percent reliability rate on its network. Such is not always the casc with thc Internet. Scrvice interruptions and periods o f perfor- mance degradation are unfortunately much too common on the Internet. Many libraries prefer to maintain dedicated links to OCLC's private net- work for thcir production cataloging environment to avoid the vagarics of Internet access. Libraries with dedicated OCLC access can use Internet access to supplement the OCLC access during busy periods, and can use Internet access in the event of a service interruption on thc dedicated nctwork.
TLP
I n 1992, OCLC introduccd a totally new approach to providing access to its services called thc Telecommunications Linking Project, or simply TLP. The previous access methods involvcd the use of OCLC-supplied equipment of various sorts, whilc TLP relies almost completely on library- supplied equipmcnt. Through TLP, the library connects its existing TCPI IP nctwork to OCLC's X.25 network via a 56 Kbps telecommunications link and a routcr that translates between these two network protocols. OCLC nccd not provide any hardware or other communications cquip- ment to the library. The library provides the router which provides access to the TLP link.
A TLP implcmentation provides a fixed number of virtual circuits between the library's network and OCLC's systems. The number of virtual circuits represcnts the number o f sessions that can be open simultaneously with OCLC services. A l l computers on the library's network are eligible for OCLC access, provided they have the right network softwarc and access to Passport. TLP accommodates a very disperscd model of OCLC access, which contrasts with the other methods that concentrate OCLC use to dedicated terminal or microcomputer stations. Through TLP, as well as the other mcthods described above that provide access to OCLC on a network, i t is possiblc to provide access to OCLC services to all library computers.
On the library side, TLP relies on a standard networking environment, usually TCPIIP. The library wi l l have a local area network and all comput- ers that access OCLC services must connect to the network. For TCP/IP networks, uscrs' computers must have TCP/IP nctwork software. While it is possible to use the DOS Passport to access OCLC services in a TLP
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
nctwork, Passport f o r W i n t l ~ w s is t l ic ideal rncl l~cr i l . Passpurt for- W i n d o w s is :I s t ; ~ n t l ~ ~ r t l W i ~ ~ s o c k - c o r ~ ~ p l i ; ~ ~ i t application, ~IIILI w i l l operate 011 :illy cumputer that has hccn c c l ~ ~ i p p c t l w i t h TCPI IP network sol'twarc. A\ IIUIII- Ihcr o f prot lucts arc ; ~ v ; ~ i l a l ~ l c h a t prov ide tl ie rcqu i rcd TCPI I I ' r ~ i v i r o n - n icn t l o r W i n d o w s 2,s. and avl i ic arc ; ~ v ; ~ i l ; ~ h l c ;i t l i t l l c or n u cost. W i w clowsO5 ; ~ n d W i n d o w s NT Workstat ions c o m w i t h this capal?il i ty h i l l in .
The w o r k s k ~ l i u n cnvircmmcnt recluircd to use T L P is Jcvc lup ing i n most I i l x ~ r i c s . T h e o v c r w l ~ c l m i n g trend i n ne twork ing is t oward a I'Cll/ll'- h:~set l nc twork . Access to t l ic ln tc rnc t and t l ie t l e v e l o p ~ ~ i r n t ul'"111trancts" requires in tcgr ;~ t ing 'I 'CPIIP software in to nn organizatiun's desktop com- puters. Sincc Passport fo r W i n d o w s i ~ s c s csact ly the same nctwork cnv i - ronment for Jcsktop computers ;IS programs such as Nctscapc's N : l v i y t o r and Micrcxr) f t 's ln tc rnc t Explorer, T L P is qui te consisten1 w i t h the nct- w t ~ r k t l cvc lo lmcn ts t l i :~ t arc g o i n g on i n l ibrar ies anyway.
Onc of the l imitutions o f T L P is its primary or ient~l t ion 1 1 ~ ; 1 r d Windows- hasecl computers. I n many ways this is not a ma,ior l i~ i i i ta t ion since this is the domin;~nt computer p la t l i~ rn l . UOS-based computcrs can he configured to access TIJ? though in most cases i t is n ~ u c l i cnsicr t o implcnicnt Windows. O C L C otfcrs softwarc (LAN drivers) that w i l l a l low D O S Passport to opcrutc w i t h ' fCPIIP networks: bu t i t is sumewl ia l compl ic ;~ tcd to instal l . O C L C of fc rc t l P;~ssport o n l y l o r D O S and W i n d o w s computers. and is e l i d ing suppurt of the D O S vcrsion on .lanu:~ry I, 1998. A t ahout the aamc t ime that TLP was m;ltlc nvail;~hle. OCLC also rcle:lsed a prot lucl c :~ l l ed Gtlte- way. T h i s su l tware runs on ;I U n i s ccmputcr and prov i i l cs ;~cccss to OCLC: t u cclmputcrs that cannot run P:~ssport. T l i r o ~ ~ g h G;~tcw;~y. l ihrar ies cc i~ l l t l a l l ow their M x i n t o s l i computers and U n i s - h ~ ~ s c c l wo rks ta~ inns to access O C L C .
The router used k i r T L P w i l l have at Icilst t w o inlcrI';~ccs, a scri;~l intcr- I:~ce wi th connects to h c Sprint n iodcm via a V.35 scr i ;~l c ;~h lc . T l i c routcr's Etl icrnct intcrfclcc connccls t o the l ibrary's nc twork . T l ic router is then c o ~ i l i g ~ ~ r c d I0 per form a translation between I l ie X.25 prolucol and TCPIll'. Cisco's ~ O L I ~ I - s t l~;~t ~ p c r a l c t l ie Enterprise version o f i ts Internetwork Opcr- at ing System (IOS) l iavc this c:~pahil i ty. W h e n conl' iguring the r~ iu tcr . ;in 11' x l t l rcss is nssignctl t o the router's Ethernct intcrfacc, and a second x ldrcss is usctl I;>r the X.25 translntion. II is this Iattcr adtlrcss that one ~ ~ s c s to connect 11, O C L C . Figure 3 i l lustrutcs l l i c T L P connection ~nct l io t l .
One (11' the d is i~dvan lagcs o f T L P invo lves its cost. T l l c 56 K h p s X.25 tc lcccmmunicat iuns l i nk rccluircd for a T L P irnplcmcnt;lt ion costs ahoul ;IS
m u c h as 4-5 9GOCI bps mu l t i d rop l incs. T L P targets tlrc largcl- l ihrar ies that WOLIILI o t l i c rw isc 11ccd fou r 01- m o r e mu l t i d rop l ines to suppcwt their O C L C ; I ~ C ~ S S ncctls.
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
124 OCLC 1967-1997: Thirly Years of Furthering Accers to the WorldS Itlfortnatiot~
FIGURE 3
TLP Access Model PCs connected to Network: Winsock-compliant TCPIIP stack and Passport for
X.25 to TCP/lP Translation
DEDICATED TCPIIP
OCLC's most recent development in telecommunications methods involves a product called Dcdicatcd TCPIIP. This access method resembles TLP, but uses more up-to-date data communications methods. This new service relies on frame relay packet-switching technology and native TCPIIP nctwork protocols rather than thc proprietary OCLC Proto- col over the X.25 packet-switched network.
OCLC Dedicated TCPIIP service is not Internet access, i t is a virtual private network and can only be used to connect with OCLC services. Libraries that havc Internet access may want to consider OCLC's Dedi- cated TCPilP service to avoid the hourly connect fees that OCLC charges for access to its services via the Internet. Libraries can fairly easily calcu- late the hreak-even point between the number of hours of Internet access to OCLC versus the cost of maintaining a Dedicated TCPIIP linc. Dcpcnd- ing on the quality of the library's existing Internet connection, it is likely that OCLC Dedicated TCPIIP service will be more reliable and offer more consistent response time. The Internet is subject to unpredictable failures and dcgradativn in pcrformancc during pcak pcriods is common.
From the library's perspective, Dedicated TCPIIP works much like TLP. The library must have a LAN with support for TCPIIP network
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
protocc~ ls fur cacli P C that w i l l access 0C:l.C. l'hc l i l i r x y m u s l p r w i c l c a router por t crr intel l igent sw i l ch port ( rout ing funct ional i ty 11r~1st hc : ~ v : ~ i l - ahlc and supported). OCLC w i l l install i ts u w ~ ~ router that w i l l in lc rk lce w i t h l hc library's router. Passpurt fu r Windows w i l l I i c the p r i m : ~ r y access sol' lwarc 1~ O C L C Cat ;~ l i rg ing and Restruvcc S h a r i n ~ . w l i i l c tclnct. W c h browsers, and 239.50 cl ients cun he ~rsccl l o ;~cccss cithcr OCLC scrviccs such as FirstSc;~rch. Figure 4 illustrates tl ic Dctl ic;~tccl TCPI IP access ~nel l i r ic l .
Dcclicatccl 'l'C3'IIP o f fers scvcr;il :~dv:~ntagcs over TLP. Frame Rclap is a morc c f f i c i cn t tc lcco~i i~ i iun ic : t t ions pro toco l than X.25. For the r c la l i vc l y low-spcccl l incs ~ ~ s e c l h y OCLC, frame rclay is l hc o p t i m u m lecl inology. W h i l e A T M (Asynchronous 'l'ransmissinn Mode) is gcncr :~ l ly considered t h r hcst sw i t ch ing technology I'or high-speed network ing. the I ' ra~nc rc lay c~pcralcs most c f f i c i cn l l y fo r :~pp l ica t ions i n tlrc muclcsl -56 K h p s tci 250 K h p s range. W l i i l c tlrc in i t ia l deployment o f 0CL.C's I>cclic;~lctl T C P I I P service w i l l o p e r a k v i : ~ f rame rclay services. r n i g r : ~ l i o ~ i t o ATM w o ~ l l d Ix relat ively easy s l iou l i l l i ;~ndwi t l t l i needs increase ~ l r a n ~ a t i c a l l y . Such migra- t ion w o u l d l i c transparent lo tlrc end user.
Dcd icatcd TCPI IP SI~CWICI I ~ C more c o s t - ~ f f e c ~ i v c 11i:ln I'1.P. I noled ahuvc a l i l i ra ry must replace a t Icast 3 t o 5 mul t i d rop l incs wi l l1 a single TLP l ine Lo hrcak even i n cost. OCLC has rcccrit ly annuuncct l p r i c i ng I'or this scrvicc and thc p r i c i ng fur thrcc or morc works t :~ t ion l ihrar ics is the
F I G U R E 4
I Dedicated TCPIIP Access I PCs connected to Network: Winsock-compl~ant TCPilP Library corn uters can
Windows @i,-ral~~ a c c ~ s s $ebbbased resources at OcLc usmg
standard web browse~s Local TCPilP
Network
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
I26 OCLC 1967-1997: Thirty Years of Furtheritrg Access to the Worldk Itrformutioti
same as they would pay for multidrop. This cost difference makcs network access to OCLC accessible to smaller libraries.
A wider array o f OCLC services can be supported through Dedicated TCPIIP. One of the recent developments in OCLC services involvcs 239.50 access to Worldcat. This service relies inherently on TCPIIP and cannot easily work over TLP connections, but wi l l be supported in the Dedicated TCPAP service. Libraries may access any of OCLC's Web- bascd scrvices through this method, including Firstsearch, OCLC First- Search Electronic Collections Online, and other OCLC Web servers including the OCLC Home Page. As OCLC migrates more of its scrviccs to a Web-based environment and as libraries deploy networks that support TCPIIP protocols, the Dedicated TCPAP service wi l l be the ideal access method.
OCLC's Dedicated TCPIIP service fits well into the current evolution o f technologies. Even though the field test o f the Dedicated TCPnP ser- vice has just begun, this access method promiscs to grcatly simplify thc process of gaining access to OCLC's services for both large and small libraries.
DIAL TCPIIP ACCESS
Since 1974, OCLC has offered some sort of dial-up access to its system for computers and terminals equipped with a modem, through a standard telephone line (see Table 1). Many OCLC member libraries cannot afford to have dedicated terminals and prefer to access OCLC services through the dial-up method and pay an hourly connect charge. The OCLC Termi- nal Software, the DOS version of Passport, and Passport for Windows each were designed to support dial-up access in addition to equipment directly conncctcd to the OCLC network. Computers can use other termi- nal emulation software to connect to OCLC services, but only OCLC's softwarc can fully support fcaturcs such as diacritics. OCLC offers dial-up access through value-added networks such as Compuservc as wcll as through its own dial-in servers. This dial-up service operates over an asynchronous serial terminal emulation session.
I n conjunction with thc Dcdicatcd TCPIIP service, OCLC also plans a dial-up version o f TCPIIP access. I t has become common for computers to use SLIP or PPP software to connect to Internet Service Providers, corpo- rate networks or campus networks. This software does not rely on a serial terminal session with a host computer, but rather establishes a TCPIIP network link with a remote network. This link operates much the same way as a LAN connection, but uses a modem and a telephone line rather
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
TABLE 1
OCLC Online System began on a single Sigma 5 computer Use of the Spiras LTE Terminals lntroduction of the MI00 Terminal Dial Access lntroduction of the MlO5 Terminal M300 Workstation First Tandem computer: Database Processor OCLC Online System expanded to four Sigma 9 computers A second Tandem computer added as Network Supervisor All computer equipment moved from facility near Ohio State to new headquarters on Frantz Road lntroduction of Communications Controller-up to 8 asynchronous connections First OCLC System reached its largest configuration, with 17 Sigmas and 64 Tandem computers New OCLC system implemented on Tandem computers (Nov 26) OCLC completes the installation of its new X.25 packet-switched telecommunications network, a $70 million project Transfer of cataloging operation to new OCLC system complete (December) Cut-over of the ILL system to new OCLC system complete TLP (Telecommunications Linking Project) available Passport for DOS 2.0 with LAN drivers: NACSINASI. NetBIOS, TCPIIP and BlOS Interrupt 14 (October) lnternet access to OCLC trial (December 17) The last of the Sigma computers was decom- missioned (February 1) lnternet Access to OCLC available to all OCLC customers 14 percent of OCLC cataloging and resource sharing operates through the Internet access (August) OCLC offers Dial TCPIIP Access (year end) OCLC will offer Dedicated TCPIIP Access
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14
128 OCLC 1967-1997: Thirty Ears of Furtl~eri~tg Access to die World's Itformaliotr
than a network interface connected to a high-speed computer network. With current modem technologies, computers can communicate on a SLIPIPPP session at speeds up to 56 Kbps. OCLC's dial-up TCPIIP ser- vice wi l l offer access to the same information products as the Dedicated TCPIIP service. This new service is completely consistent with thc gcncral trend in computer use toward PPP-based dial-up methods.
SUMMARY
OCLC's access options have generally kept pace with the evolving trcnds in the telecommunications industry and the library computing envi- ronment. I n the absence of any existing technical infrastructure in libraries, OCLC initially delivered a complete acccss solution. As libraries deployed microcomputers and developed networks, OCLC has offered access methods consistent with such an environment. The overwhelming trend in the current era involves the Internet and Intranets. I t seems that the wholc computing world is rapidly converging on TCPIIP networks and Web-based information systems. OCLC has workcd quickly to re-orient its networking paradigm towards these technologies. Libraries wil l do well to embrace these new access methods to make OCLC services just another component in their network-based information cnvironmcnt. Proprietary acccss methods and equipment are remnants o f the past, while integrated networks rich in information rcsources are required for libraries to be the information leaders o f the future.
NOTES
1. Breeding, Marshall. 1991. "Multipurpose technical services workstations: Access to NOTIS/OCLC/GTO with a sinlrle microcornouter." Library Hi-Tech, " Issue 35, Vol. 9, No. 3: 69-81,
2. Breeding, Marshall. 1992. "OCLC Connectivity: Current Models, Network Integration, a; Future Directions" OCLC Micro 8:4.(~u~ust): 28-36.
Dow
nloa
ded
by [
Cor
nell
Uni
vers
ity L
ibra
ry]
at 2
0:29
14
Nov
embe
r 20
14