CA2176534C - Serving signals - Google Patents

Abstract

Output signals are served from a serving device to a plurality of browsing devices connected to a network. The output signals represent commands executable by each browsable device so as to display viewable data in accordance with specified page formatting. Requests from browsing clients are identified which contain information relating to the data itself and the display format for the data. The data is read and processed so as to combine a representation of the viewable data with executable instructions. The signals are then supplied to requesting browsing devices, after effectively being assembled as a real time on-line process.

Description

21 76~i34 P4C~P01-CA

SERVING SIGNALS

Tlle present invention relates to serving signals to browsin~
clients, wher~in s~id signals represent con~mands execut~ble by sai~
5 l~rowsin~ rlients for ~enerating stru~tured pa~es of hurnan ~Jiewable data.

.--~ INTROt)UCTION
The serving o~ hum~n viewable data in re~ponse to client requests has been known for some years in the f~eld of c~ble televlsion 10 syst~ms. Star type systems in parti~lar ~llow view~rs to make sele~tion~ res~lting in rernot~ swit~hing being performed so as t~ route a selecte~ signal from a ~i~tribution head to the request~ng viewer.
Cable t~levision systems are us~lally based on standard broadcast television signals and, as a result, a sub~tantial transmission bandwidth 15 is required in order to provide each ~iewable page of data. Recently.
~lempts have been made to compress video data, by impién~enting recommend~tions using standards such as IV PEG, so as to facilitate the distribution of vi~eo signals over channels of substan~ially less bandwidth. Thus, it is now possible to transmit lo~v quality vldeo signals 20 over conventional telephone lines using '.empo~al and spabal cor"~r~ssion te~hniques.
It has also been possible to distribute hum~n viewable dat~ in the form ~ enooded text for a number of year~. The tr~nsmission of text.
o~en using ASCII coding, re~uires substantially less bandwidth than the 25 transmissi~n of video si~nals and for a number of years data of this type has be~n transmiffed oYer conventional telephone c~bles.
A problem with transmitting oon\~entional d3ta text, ~omp~red to irnags related video signals, is that the quality oS pres~n~ation and ., -2 1 76~34 overall ~raphical forn~t is significantly impair~d. For this reason, traditionaily, the transmission of data, as distinct from video, has tended to dev~lop only in specialist fields where presentation was not ~onsidered p~rticularly important. Very often, for example, the data 5 being rec~i~ed wou~d be considered as b~ing quite valuable and very often it woutd be possible to iUstify the r~typing of i~lf~ ation as and when raquire~.
A further problem with the dissemination of ~ata is that many standar~s and ~,onventions have de~eloped over the years therefore, 10 tr3c3itionally, users have needed to develop techniques ~or accessing di~ere~t data sources, which in itself has tended to ~on~e a specialist activity.
In parallel with the tendency towards bandwidth reduction in the transmlsslon of video signals, there has also been a tendency towards 15 improving the graphical forrrlat, structure and present~tion of what would norm~lly be conslder~d as tex~ural data. Thus, although d~ta may ~e transmitted within a text-based environment. such as within ~e internationally accessible netNork known as the "Internet". there has been ~ tendency toward~ including formatting structures ~uch that a ~0 substantially data-driven source ~ould be vlewed by a user on equipment which woul~ present the data in a form substantially similar to that of a video image. Thus, the ~wo arts of Yideo signal processing and ima~e data processing are coming closer together and rea~hing towards a comm~n aim of pro~/~ding what appears to be a hlgh 2~ reso3ution, hi~h ~andwidth, high quality image ~y transmittln~ data o~er low bandwidth transmission mec ia.

For a number of years, cable television systenns have been used to provide in-home shopping hcilities ~nd, given their two-way capabilitie%, it is possible to inst~ll a le~el o~ inter~tivity wi~hin such 2 ~ 76~3~

systems. On-line systems facilitate a higher level af interac~ivity ~nd, in addition to making pa~icular selections in response to in~ages being bro;~d~st, it is a~so possible to select particular ima3e pages by browsing through c~tal~gues and tree structures etc. Thus, given an 5 ability to dlsplay high quality im~ges, similar to those a~ilable through video based systems, on-line systems present en~lironll~e,lL3 with subst~,ltially rnore interactive capabilities. Howe~e~, it Is appreoi~ted that in many of these envlronments the quality of imagss must be r-- slgnifi~antly enhanced in ~rder to att~ln a broad customer bsse.
10A known w~y of improving the qu~lity of ima3e~ derived from text-b~sed systems is to add formattin~ cornmands or ~nst.uetions to data strings. These instructions control operations of a receiYer, such that the signals are pro~ssed in such a receiver, to ensure that the transmill~d signals are pr~ces~ed in such a way as to generate a high ality video image th~t is ~pabie uf being displayed at a requestlng client's terminal.
In ad~ition to improving the quality of displayed im~ges, such an approach also facilitates an improvement in system compatibility. Thus.
r~ the incoming control signals are execute~ by a reoeiver's tenninal in a 20 w~y that is con~pa~ible w~th the receiving system. Thus, the output signals may be cons;dered as executable instructions that cause operations to ~e performec upon the viewable data ~n asc~rd~nce with ~he lo~al c~n~traints.

Thus, the use of systems of this type must be di tinguished from 25 simple iocal database systems in which ~11 operations of the system are iocally controlled and no account whatsoever needs to be taken of remote facilities and characteristics. Su~h systems are ~ignificantly diff~rent in that d~ e systems only transfer data that is subsequently manipulateci by controlling pro~rams. ln mark-up lang~lages the forrnatting cornmands ~re embecded in the form executa~le commands, executable at the receiving station, so as to perform operations upon the viewable data supported by the local plafforrn and peripherals.
Mark-up lang~ages of this type may ai~o include other ~apabilities previously not found in simple dat~ distribution systems. In pa~icular, a highly v31ued additional feature is the ability to automati~ally re~eive additional files from anywhere within the over311 network. Such a pro~edure is possible be~ause, ~s preYiously stated, the mark-up langua~e i~ effectively executed by the loGal ~ lr~",., and these executable pr~edures may include procedures for making external calls to files h~ld anywh~r~ within the accessible ne~work.
Frcm a user's p~int of view, such links may be considered as providing a level of multi-dimensionality within a viewable document in that a particular word or phrase may be selected, v~here~fter an expansion is provided or related doouments are identifiecl. in order to distinguish such documonts ~rom ordinary self-contained ~ocumen~s, text of this type is commonly referred to as "hypertext". Similarly, such links n~ay al~o be made to full moti~n video sequences or ~udio sequences etc. and such an environment may be referr~d ~o as "hypermedia".
An exampie of a particular re~on~mend~tion under which sisnals incl~de ~ommands executable by browsing clients is the "hypertext mark-up langua~e" (HTML) developed at CERN durin~ the late 1950~
and e~rly 1g~0s, which has recently becom~ a part of the Internet through a serv~ce known ~ the "Worl~ Wide Web". An (HTML) flle is essentially an ASCII document intersp~rse~ ~it~ tags for formatting text and displayi~g ima~es. The tags graphicaliy repr~sent instruc~ions which are acted upon by a r~eeivers browser. confi~ured to r~nder text or g~phics. T~e browser has full ~ntrol of how the page is displayed, 2~ ~6534 therefore it is possi~le :o generate a wide range of p~ye lay~outs from a m~de~t set of (HTML) tags The Internet is an extreme example of a neh~orlc in which many different types ~ plafforms, having vario~s protoc~ls an~ processing 5 capabiliti~s~ may be int~rconnected using highly distributed control instruction sets. As previously suggestec~ systems of this type often provide an environment in which a user may "browse" through m~ny files and structures. ~onsequently environments to faciiltate the reception ancl oon\fersion of HTML files ~re commonly kn~wn as 10 "browsers". rhu~, a browser is an application capable of inl~r~retir,~
and d;spl~yin~ d~uments recei~ed in HTML in such a way th~t the in~nation is displayed to the user in ~ forr~ comp~tible with th~ user's available equipment. Thus, using sophisticat~d terminal equipment, provided with an appropriate browser, it i~ possible to displ~y text-based 15 data at a quality that is perceived as being substantially simila~ to that of full bandwidth video, while significar tly reducing the l~vel of ~andwidth r~uired in order to dlstribute the inform~tion. Thus. as previousiy stated, the purpose of the brow~er is to substanti~lly impro~e the quality of the displayecl image ~uch that a client user i~ presented 20 wi'~h a high quality video image, if suitable equipment is availa~le. In ~ddition, the browser ensures that comp~tibility fs achieved between the local system facilities and the transmitted data. Furthermore, hypertext links may be defined within the doeument that are executed by the b~wsar so as to make additional doc~lmont$ a~ailable in response to 25 user driven selections.
Clearly, it is only possible ~o~ elient users to make use o~ these sophisticated lan3u~ges if networks include accessible data sources.
HTML files n~ay be stored in ~le structures that ~re sul ~5t~ Itially ~imilar to conv~ntional data formats. Requests are ~a~e, via client b~owsers t~ applications m~intained at a distrlbution node, commonly referred to as "servers".
Both browsers and servers represent ~ppli~ations which must be made available when requested ~It~ough, during substant~ally q~iet period~ of operation. there are not ~tually required as such.
Procedures of this type, emlJedded within sy~tems and substantially transpar~nt to operators, have become known, collectiv~sly, as "daemons". Thus, in op~ration~ server daemons intermittently in,e"~at~ selected po~ts for in~oming signal requests. I~ respon~e to these req~ests, servers may make appropriate housekeeping ~nd secunty operations, whereafter, if possible, tlte sele~t~d file is identified and suppliecl ~o th~ requesting browser.

In eariier sirnple ASCII based text sy~terns, the gener~tion of text in ~ form suitable fcr transmission over networks involYed reiatively easy oper~tions. Generally, documents could be accessed from text files or databases ~nd transmitted di~ectly across the network. At the receiver, the input data wouid o~ten be buffered, but thereafter it could ~e supplied directly to line printers, or similar devices. thereby producing a listing or print out of the transmitted ASCII text.
As previously sta~ed, HTML allows sophistJ~ted formatting structures to be adde~ to the viewable data so as to present a subst~ntially more appealing image to client users However, a n~ajor disadvantage of using such systems is that it is necessary ~o ~onv~rt source data into HTML ~rm ~efore it m~y be transmitted ~ver the n~twork. In practice, such a procedure is presently performed m~nually and a significant number of man hours m~ be requir~d in order to ~on~ert originating t~xt into an appropriate ~l~ML v~rsion suit~ble for distribution throughout the network.

In some environments, such as research envlronments etc., data may be r~quired for si3nific~nt p0riods of time and under s~h circumst~nces It is pos~i~le to Justify the time ancl ef~ort required in order to mark up the text for distribution throughout a network in an appropriate form. ~lowever, as i~ well known in the m~azine ~nd newspaper a~ts, some forms of data. although initiafly highly va!uable, m~y ha~e ~e~ short "sh,elf iives" and, even the next day, they may be~ome virtually wsrthless. Thus, many forms of existing paper publications may be witl~held from electronic p~Jblishing if the amoun~
1~ of time an~ effort required to ~overt the text-based ir~formation in~ a f~rm suitabl~ fo, dlstribution t~roughout networks is ~ignifi~antly large.
hlrthermQre, in mOny sit~l~tions! the extent to whi&h the time scale for per~orrnin~ ~n exercise may be redue~ by increasing manpower~ may be re~tr~c~e~, given that it i~ only po~ible for one person to work on 1~ one page at any one instant.
Traditional marking-up is a la~orious task, gi~en that, by its very n~t~lre, the ~ct~al transmitted dat~ looks very different from the viewed im~ge. In most sit~tions, it is necessary ~or a level of marking-up to be performed, whereafter the data is tr~nsferred to a locally si~ua~ed - 2Q browser, so that the resulting viewable image may be eonsidered, before further oper~tions ~re performed. On~e ~reated, files are IGaded on appropriate storage devices and thereafter made a~ailable to requesting ~ust~mers.
Systems ~re available w'nich facilitate the creation of (HTML) ~5 documents. For example, it is possible to process documents generatedunder ~,hrotd processing systems, such ~s ''Word ~r ~ndow~", whereby, in response to m~n.~l operations, (HTML) tag~ are added to human viewable text. Systems of this type are sol~ under the Tr~de Marks 'WebAutholJ' and "Intem~t Assist~nt"

It is well known that traditional newspapers tend to change sligh~ly ove~ a day, as various eciitions are modffied so as t~ take aocount of recent news items. Thus, very often, a late ~clition of a newspaper will carry a ~ir~erer,t main story to that of earlier editions.
5 Within electronic environments, there is an expectation ~or 3n even higher level of updating ~nd inter~tivity Presently, in order to satis~y this expect~tion, it would ~e neces~ary to continually update pa3es manuaily.
Systems have been propose~ in which clients are given the 10 impression tha~ a ntag~zine has been tailored to th~ir partieular ne~ds.
Thus, systems are kno-~n in which parti~uiar selections m~y be made thereby tunir~ documents to wstomer re~ulrements ~ problem with known ~ppro~ches of Ws type is that each page viewed by a elient must be pr~cr~ated, ther~by doubling the num~r of pages required 15 each time a decision point o~curs. S~ch an app~o~ch may have applications in p~rticular environments but it ~an be appreciated that ~s the num~er of notion~l pages increases, the number of actual pages required within the system becomes extremely large and th~ task of creating and maintaining ea~h of these pages manually would be hishly 20 laborious and very oKen make the syst~m uneconomic. This is particularly th~ case when dealing with publiGations which, in their conventlonal paper form, are perceivecl as having rel~tively low value or o~en no int~insic value at all. Such ~ situation wo~ld apply to free newspapers and ~dvertising catalogues etc.

2S SUMMARY OF THE INVENTtON
According to a first aspect of the present invention, there is provided apparatus for serving output si~nals fron~ a serving device tc a plurality of ~rowsing devi~es connected to a network, wherein said o~tput signals represent comm~nds executable by eaGh browslng g device so as to display viewable d~ta in accordance ~vith the specified page format, c~ rising: means for identifying req~ests from ~rowsing clients that define a request for ~ecifiied viewable data with commands for displaying said data in a specified format; me~ns for 5 reading data representing said viewa~le d~ta; Means for pro~es~in~
said read data so as to combine a representation of said viewable data with executab~e inst~uctions; and means for supplying out~ut sign~ls to the requestin~ browsin3 d~vice deriveci fr~m said processed d~ta In ac~ordance v~ith the s~id inventlon, it is not necessary to sto~ e 10 all output files as predefined HTML fil~s. ~iTML outp~t instructions are generated "on-th~fly" in response to requests made by users.
The apparatus may be used within many networlc configurations.
In a preferred embodiment, the network is the Internet.
Prefer~bly, requests are made by browsln~ cllents in the form of URLs 15 and output signals ar~ supplieci ~a~k to browsin~ d~vices in the .~orm rf hypertext mark-up language ~ommands.
The ~pparatus rnay be use~ for supplying any type of ~at2 to users, partic~llariy text data and graphical data.
~.
Preferably, view~bie ciata is read from conventional dat~bases in ~0 response to a URL bein~ receivecl, where~er this data is p~o~essed so as to confi~ure it into HTML commarlds.
In a p,~f~rr~d embocliment. dat~ is i~entified within ~atabases by means of an index, such that the rel~tionship between indice~ and ~he a~cess dat~ may be adjusted. This facilltates the updating ~f d~ta 25 without needir~ to g~nerate new HTML code.

BRlrF DESCRIPTION OF TffE DRAWINGS
Fisure 1 is a diagrammati~ representation o~ part o~ the international ~3ta distribution ne~work known as the Intemet, ha\~ng a ~ . --2 ~ 76534 plurali~y of servlce pro~iders and a plurality of servic~ usPrs;
implemented using a plurality of network topolo~ies.
Figure 2 shows an example o~ a typical seNice provider network of the type shown in Flgure 1, including a l~cal area network and a serving host;
Figure 3 de~ails the se~ing host identified in Fiyure 2, including a processlng unit and a random access memory for storing instruc~ions executable by said pro~essing unit;
Fi3ure 4 represents a processing enYironm~nt specified by the proces~ing unit and its assoGiated instructions created ~y the precessing unit aQ~ its associated memory shown in Figure 3, in~lud,r.g a hypert~xt transport proto~ol daemon and on-line pr~c~ssing procedures in accordance with the present invention;
~i~ure 5 illust~te~ the operation of the hypertext tr~nsport protocol daemon identified in Figure 4 in response to teceivin~ an input URL r~uest ~nd in~luding an i~entification of initi31isati~n proce~ures and procedures for performin~ on-line processing;
- ~igure ~ shows requesting user devices, including ~ processing deviGe and a visual display unit, f~ ~0 Figu~ 7 illustra~es a typical displ~y shown on the Yi8Uiill digplay unit identifie~ in ~igure 6, in response to instructions being supplieci to the user from a server;
Fi~ure 8 show~ an example of instructions in the form supplieci to the browser, in order to gen~rate the display shown in Fi3ure 7, Figure 9 ~etails the initialisation proced~lres identified in Fig~re 6;
~igure 10 d~tails the on-line procedur~s identifie~ in tj9UFe ~, incl~ding an indl~tion of procedure~ for ~onerating HTML pa~es;
Fiaure 11 ill~sl~tes the retatiorlship between ser~ing components when conflgured to supply HTML pa~e~ to a requesting device;

Figure 12 details pro~edures for gener~ti~g HTh1L pages id~ntified in Figure 10, including a ~ep for exeGuting a f-~nction string;
Figu.e 13 det~ils proceclures for executing a function string, including a ~nction execute step; and Fi~ure 14 det~ils fun~tion execution steps used to gener~te fines of output comm~nds of the type identified in ~igur~ 8 DETAII ED D~C~IPT~ON OF THE PREFER~ED ENIE~ODIMENT
A diagramma~ic represent~tion of part of the Int~rnet is shown in Fi~ure 1. An intern~tional d~ta c~mmunication network is provi~
10 represen~ed diagrammaticall~f ~y region 101. Access to this network is provided over data ch~nne's 102, that are in t~lrn ~onne~ted tc~ service nodes 103. Service nodes 103 allow ~se~ to gain access to th~
Internet with varying levels of tran~rnission bandwidth.
In the example, a loca! area net~ork 10$ is provided with a high ~;~ndwidth link 1~ to an In~ernet service provider 103. The ~etwork 105 includes servers, that supply data to the Internet in response to reque6ts m3d~ ~y u~ers. Pr~sently, users ~re given accas~ to the Internet over channels providing traffic oapacities from 14.4K blts per _ second (telephone dial up) to 100 M bits pPr second and beyond, w~hen im~em~nted using optical techniques.
A low ~ width user 106 communio~t~s w~th ~ service provider 103 ~ria co-operating modems 107, 108 conne~ted vi~ a transmission cable 109. Many usefs of this type may ~o~ess inforrnation from a server, such as ser~/er 1G5.
2S Nehvork 105 is detai!ed in Fi~ure ~. The ne~work ~omprlses a fibre distributed data interface (FDDI) ~ackbone nng 201 having four ro~ters 202, 203, 204 and ~06 c~nne~t~d thereto. Kouter 20~ is a token rin~ router which routes data betuveen a token rin~ network 206 and the FDD~ b~skbone ~01. In the example shown in Fisure 2, a fi~st h.ost processin~ system 207 and second host processing sys~em 208 are connec~ed to the token ri~g ~C6, thereby facilltating cornm~nication betv~n said hosts 207 and 208, along with c~mmunication between said hosts and the backbone ring ~01, via token ring router 202.
Ahost processing system 209. ~nd a host pr~c~ssin~ syst~rn 210 communicate ~Jia an sthemet n~twork 211. The ethernet rletwork 211 also allows cornmunication between ho~ts 209 and 210 and the back~ne ring 201 via ethernet ro;Jter 203.
The back~on~ ring also communicates wi~h an asynchronous 10 tr~r~sfer mode (ATM) network, including a first ATM host 212 and a second ArM hos~ 213. Information .for dlstril~ution to the Irltemet is generated ~y "serving operations" executed by host 212. rhis host communic~tes with the bac~one rin~ 201 via the A~M router 205, which in turn facilil~es communication to the Internet itself via Internet router 204 and an Internet line driver 215. ~his facilitates the transfer of data to an Intemet service p'ovid~r, as shown in Figure 1 The present embodiment i~ dirscted towards providing ~ITML
en~ocled data, in accordance with the HTML r~c~, n" ,~ndations implemented over the Internet ~s a servioe known as "World Wide 20 Web". However, the invenUon as a whole has broader application~
particularly when it is neces~ary to process human view2ble data in combination with signals r~presentin~ a selecte~ display structure, such that comm~nds a~ executabie by remote browsing cli~nts.
Servin~ station 21~, as showrl in ~i~ure 1, ser~es files, processed ~5 in a~cordan~e with t~ est~lished hypertext mark-up language (HTML) to bro~sing clients Yia the In~emet. P~ browsing ~lient makes a request for the inform~tion to be ~upplied and this reque~t is identified by a se~ing station, such as station 212, which responds to said request by returning the int~,r,l,~lion via the lnternet conn~ction to the browsing 30 client device Onoe a requesS ha be~n re~eived, first signals are processed by the serving station which represcnt th~ human viewable data. Second signals are received which ropresent a se~ected display structure. These two sigr:als are processed in order to produce an HTML o~tput. Ho~ever, t~is processing step only takes place after the 5 client req-~est has been received such that the first signals and the secon~l signals are processed to produce output signals in the form of ~lient execut~b~e instructions which are then serv~d as o~Jtput signals suitabfe for exe~ution by the requssting browser. In this way, many pa~es of HTML encoded data may ba produoed ~utomatically withou~
10 requiring manual effort for e~ch individual pa~e. furtherr!lore, pages may be t~ilored for specific user requirem~nts and, in some circumstances, it may be possible to adj~st th~ extent to w~i~h this customisatiort t~kes place in response to t~e ~lients own history of use, such that topics of interest are identifie~ automati~ally ancl this 15 identification is used in order to diect i,lfol"-~ti~n of interest to the ~lling client.
The hardware of serving network 10~ i~ sho~rn in Figure 2. A
request fr~m a browsing c!ient would be received from the Internet provider via d~t~ link 104, thereby allowing the IntPrnet router to direct 20 the packet of infoll"~tion onto the backbone network 201. This p~cket would Include an address so as to identify the processing environment arrange~ to ser~e the requested information.
ATI~,1 host 212 is d~taiied in Figure 3. A central procsssing unit 301 proYides a general purpose multi-tasking processing environment, 25 po~slbly running under the UNIX operating system. The processing unit includes intern~l buses to facllitate ~ommunication with a mass storage device, such as a h~rd disk drive 302, and a randorn access n~emory 303.
Communication with external devices is facilit~ted throu~h an 30 inp~ou.put (I/O) in~erfa~e 304 which is in tum ~nnected to typical user periphetal~ such as a keyboard, a monitor and a mouse et~. In addition, the l/O devi~e 304 is connected to A~M router 205 vi~ a - n~twork control circuit 305.
A routine is exeeuted continually by the pr~cesslng unit 301 to 5 identify requests made to a p~rticular IJO port esta~lished by the i~O
~ircuit ~04. Thus, ~ packet received by the backbone 201 includes an ~ddre~s that enables the networt~ control interface 305 s~eh ~hat said control~er may direct the packet to the l/O interface 304. Thus, the packet identifiecl by the network controlier 305 will be supplied to parffcular port of the IIO device 304. The processin~ unit 301 will identify the fa~t that data has been supplied to the relevant port 3nd establish a connecti~n, effe~tively placing the system into an acti~e mode. Once placed in its active mode, the packet of data passes through the tJO device 304 to b~ome ~ packet of information which is 15 then held under the control of the operatin~ system of the processin~
unit 301.
In response to receiving this information, the processing unit 301 is ~rr~nged to perform the steps identified abov~t that is, it is arr~nged to process first and second signals to produce output signals in the form 20 of client ~xecutable instructions. After this pro~essing h~s t~ken place, the resulting output signal is returned for transmission to the Internet via line driv~r 215, Internet router 204, ATM router 205, nPtwork ~ontroller 305 and t~ de~ice 304.
The processing envir~nment provided by the processing unit 301 ~5 is illust,~t~:l in Fg~lre 4~ An HTTP d~emon 401 is exeouted by the pro~essing environment 402 in order to detect requests received by the inp~t/output device 304. in response to detected request~, the pro~ssing environrnent 402 is arrangec to supply predetermined HTML
files 403 to the IIO device 304. In addition, it is also possible for the 30 HTTP daemon 4Q1 to identify c~l "m~n yate~Yay inte~a~e biriary programs ~CGI.BIN pro~rams) which are executable in~tructiorls within tho proccssing ertvironrnent 402 and results in id~ntified files being supplied to the IIO d~vioe 3~4. The GGI.BIN files are ~apable of operating in res~Jonse to variables, including information identifying the 5 type of browser, the host name of the system and details of the client requesting informa~ion etc. Facilities ~ this type are available within existing HTTP servers. However, in addition, it is po~sible for the da~mon to re~pond to requests where the output ~TML file will ~e produ~ed "on the fly" in response to instructions identi~led as "on~line 10 processing". VVhen requestecl, the on-3ine pro~essing will receive human ~iewable da~a f~m a database 406 in combination urith file structures frorn a fi!e structure sourc~ 407. Thereafter, in response to instructions from the on-line pr~cessing system 405 the processing environment 402 will process hurnan viev~le data in con~lrlalion with flle structure 15 data to produce tlTML output files for the IIO device 304.
T~e HrrP dael~on procedures identified at 401 in Figure 4 are detailed in Figure 5. InitializaUon procedures are implemented at step 501 on start up, wherea~Ler the appropriate port is into"~gat~d at step 503 ~flcer waiting for ~ precletemlined p~riod at step 5~2 The ~0 procedures shown in Figure 5 a~e executecl within a multi-tasking environment, lher~ru~t: the wait period at step 502 refers to a single task and other tasks will execute without being affected. At st~p 504 a question is ~sked as to whether a user request, in the form of an uni.form resource loc~tion (URL) is waiting at the i~ ,t~n~a(~.l port. If the 2S quest~on asked ~t step 504 is answered in the neg~tive, control is re~rn~d to ~tep 502 ~nd the proo~ss repeated. Thus, as previously stated, the system ~erat~s within a multi-t~sking enYironn~ent, such ~s that provided by the VNIX operating system. Thus, while the particular t~sks shown in Figure 5 repeatedly loop until a URL is received. the 30 syst~m is arranged to perform other tasks.

If the question asked at step 504 is ~nswered in th~ ~ffirmative, to the effect that a URL h~s been ~etected, the URL is processed at step 5C5, whereafter valid~tion procedures are executed at step 506.
V~lidation procedur~s firstly determine whether the URL satis~ies ~n S ~cept~b'e structure and thereafter, security provisions may be executed in order to establish whether the ser~er i~ permit~d tc serve the requestin~ client. Assuming a valid UP~L has been supplied to the s~rver, a question is asked at step ~07 as to whether the client has requested ~ predefined HTML file. If the question is ~nswered in the 10 arrit~l~alive, the requested file is supplied to the req~l~sting cllent at step 508 ~nd ~ontrol is then ret~rned to step 50~. Alternatively, if the questton ~ske~ at ~tep 507 is answered in the negative, control is ~li,æt~l to step 509.
At step 509 a question is asked as to whether the on-~ine 15 proces~ing procedures have been requested. If this question Is answered in the af~lrmative, the requested file is prepared on-line ~nd s~p,~ied to the browser at stPp 5~0. AltematiYely, if the que~tion ~sked at step 50~ is ~nsw~red ;n the no~atiYe, control is direct~d to step 511.
At step 511 ~ question is ~sked as to whether an instruction has 20 been supplied to the effe~t that CGI.BIN are to be executed. If this question is ~nswered in the drri""dlive, control is directed to ~tep 512, resu~lting in the execution of the identified CGI.E3IN instructions.
Altematively, i~ e question asked at step 511 is answered in the negativet all possibillties wi~l h~ve been consldered and an error 25 ~I~es~age is returned at step 514.
Referring to Fi~ure 1, ser~er network 10~ has been ~esuibed with refe~ence to Figure& 2 and 3 and the operations ex~cuted within sald server 212 could be described with re~erence to Figures 4 and 5.
In~r."~tion from the server 212 is supplied to re~uesting clients over 30 the Internet ~nd files ~re serve~ to brow~ers in response to reque~ts made by browsers. As previously stated, ~ browsing cli~nt 106 iss~)es requests, in the ~orrn of URLs via a modem 107. A ~rowsing station 106 is detai~ed in Figure 6 connected to a modem 1~7, which is in tum connected to the Internet via communication ca~le 109. The browsing 5 ~lie~t hardware consists of a programm~ble d~vice such ~s ~n 18M
personal computer conhgured to operate as a browse, in re~ponse to instn~ctions installed from local permanent storage medium, usually a h~rd disk drive. The system includes a keyboard 601 and a visual d~splay unit 602. An operator issues commands via the keyboard 601 -10 or the mouse ~3, causing the browser to issue a ~JRL to the server.
The browsing instru~ions ~xe~uted by the termin~l shown in Figure 6 ~re configured in a form to be cornpatible with the servin~ instru~tions generated by the server 212. Thus, particular instrustions would be installed on the s~rve, 105 ~nd in order for us~rs to g~in access to 15 these instructions it would be necessary to install an appfopriate browser for execution on the user's terminal. Thus, in response to a user issuing colr"-,ands via the keyboard ~01 or mouse 603, the browser converts these instructions into a IJRL which is in tum processed ~y the remote server. This in turn res~lts in HTML
20 instructions bein~ supplied to the browser from the networtc such that the browser effectively executes these instructions in order to generate a dlsplayable ~ideo signal. The video signai is supplied to the rnonitor ~02, resulting in the human viewable information being d!splayed on the moni~r In a ~orm derived from the J ITML instructions supplied to the 25 browser as executed by the browser itself.
Monitor ~2 i~ detailed in Figure 7, showing a typic~l ~pplica~ion of the system~ In this example, on-line ~eneration of liTM~ Instrucbons are being ~Ised to present ~ home "sl~opplng on-line" c~talogue to users, ~o fflat sald users may inspect availabl~ products and place 30 orders ~or said produGts. Th~s, the interactive envi~onment ensures that users are kept up to d~e ~!th availa~le product~ pri~.es while at the s~me time allowing orders to b.~ placed wlthin a common facility.
The page shown in Flgure 7 represen~. an initi.~l c.ontents page for a servi.^e identifying itself as ~ "Home Shoppern. (this is a ~ctitious 5 publication made ~or the purposes of this description and any simfl~rities to ~xisting p..bli~ations is not intended~. The contents page allows a user to quickly seJect areas of interest in a structured way Thus, from the initial page, selecticr.s may be mad~ for spc~s ~,oods, elentrlcal goods, cc.rnputer goods, children's games and toys et.^., gardenng 10 products or .~.lothing. Tne user's termin~l ~shown in Fi~ur~. 6~ inclu.~.e~
a mouse 603 and oper~tion of th'.s rnouse results in a cursor being moved over th.- ~iewed image. The ,ma~e inclu.~es ~ g~phical i~n for .~ch of the av.~ila~le c~tegories. Thus, an icon 701 fn the forn~ of a tennis r.~cquet identifie~ a region arranged to effect a c~ll to the 15 products rela~ng to. s~or~s. Thus, the mouse may be manuaily adjusted so as to po~.ition the cursor over this icon Thereafter, a mouse button may be operated resulting in exe~ution of a hyperlink to ~nother HTML
pa~e. Thus, the identifcation of the sports i~on by the user will autc.~natically result in a new UR._ being genera~ed which is in turn 20 supplied t~ the server vla ~he network, resulting in a se~ond pase being supplied to the requesting user. Slmilarly, a graphical icon 702 of an electrical d~ill is provided for the electrical selection. Placing the cursor over this icon and operating a mouse ~utton will result in a new pa~e b~ing supplicd from the ser~rer containing electrical ~oods. Thi~ page 25 may take the ~onn of a se!cond level ~ tents page allowing further select50ns to be made. Thus, the next pa~e may identify parti~ular types of electrical goods, electrical DIY goods, white goods or hi-~i goods ete. ~imilarly, a button may be selected at this se~ond level resulting in n~w icons and products being displayed. Thus~ electric~l .

DIY goods may again be sub divided down into dri~ls, sanding machines, ele~tric screwdrivers etc.
A tl-ir~ icon 703 shows a graphical image of a computer and, similarly, selecting this i~on will result in ~ second leYel ~ ts page 5 being supplie~ identif~ing types of computer eqliipment. A fourth icon 7~4 shows ~ silhouette of children ~t play ~nd operation of ~ mo-Jse button with the cursor pl~cecl over this icon will r~sult in a c~ll being m~de t~ the ser~er and a new page being generated identifying children's game~ and toys.
.~ .
Afiftl~ ;con 705 show~ a pair of ~sacks and represent~ gardening supplies and products, while a sixth icon 70~ shows a sm~rtiy dressed young l~dy as a r~e~ns of identifying ;~ referenc~ to clothin~. Ti~us, in a ~imilar way, icon 705 or icon 70~ m~y be sele~ted, resulting in a call being made to the server for an appropriate page to be supplied to the 15 browsing client.
1 he icons 701 to 706 are high definition grapl lical images and are stored as. GlF ffles, although other types of graphlcal format may be employed. rhe informatl~n used to construct the page is derived from a d~t~base and all of the in~ormation within the ~atabase may be ~0 modified, possibly in response to changes in availability and price etc.
usin~ conventional d~t~h~se techniques. Pre~iously, all HTML pag~s were con~tructed ~nd stored as such, thereby making them availab~e when requests were iss~ed by clients. Such an arrangement is similar to ~hat identifed at step 50~ in Figure 5, where a predetermined file is ~5 supplied to a re~uesting user. In some situations such an ~pproach provi~es a pe~ectly ad~ate sol~JtTon. ~or example, technical p~pers and I ~er~nce books tend not to chan~e once they have been published an~ thereafter reference may ~e made to the~e doouments for a con~iderable period of time. However, sh~pping catalo~ues tend to 30 change at least s~ason~lly and retailers would clearly prefer to m~ke special deal~ available to customers as and when they themselvos can m~ke arrange",~n~s with their suppliers. Clearly, an inability to resporld to market changes in this way woul~ place the on-line retailer at a disadvantage when ~ompared to traditional ret~ilin~ actiYit.ies~ In c~ther 5 situati~ns the shelf-life of data may be ~ven tower. Thus, magazinç?s are monthly or weekly, while most newspapers are only valid for the partic~llar day of iSSU8. Redudng the time scale still hrther, is comrnon pr~ctice for newspapers to chan~e during production, as new news ~tems are received and developme~ts take place. Thus, it is 10 adYantageous for e~ito~s to ~e in a posi~ion to m~ke upd~tes to the di~tributed news as and when changes occur. ~learly, whon news items ~re broadcast using conventional radio techniques, the news bulletins a~e continual~y updated, thereby placing traditional news publi~ations ~t a co",F,~ra~i~e disadvantage.
In the present embodiment the viewa~le data is retained Qn a ~t~base and signals are read from the d~t~h~se, representtng ~aid data, fo~ processing in combin~tion with se~ond signals representing the way in which the i~ormation is to be formatted on the vi~wed page. In a possible configuration, H~ML code oouid be held as a te""~ t~ with ~0 ~ps therein for th~ a~ual view~ble data, such that, in respon~e to a request being made, the viewa~ie data could be ide- Itifi~d ~nd i, ,~(laced with the formatting HTML instructions. However, in the pr~f~rl~d embodiment, a pl~lr~lity of executable functions ~rs proYided at the server su~h that in response to a particular request being made ~5 a strln~ of functions are executed resulting in ~alls being made to appropri~te dQt~h~ses in order to obtain ~iewable irmsr,llation. ~his viewat~le inf~ tion is then processed s~ as to con~bine it with HTML
t3~s, to pro~e output signals for transmission to brow~ing ctients HTML instructions for yeneratir1g the viewable image displayed 30 on mon~tor ~02 are detailed in Figure 8. Line 1 inclu~es the viewable text (home shopper) ~nd this has been em~edded within tags to identify this word 7.s being at the head of the document and as b~ing a title for the whole p~ge. At lin~ 2 the tag iden~fies the start of the body of the document and within the body of the document a s~b-heading "Contents 5 Pa~e" is displayed surrounded by form~mng tags H1. Line 3 oonsist~
of ~n HTML Instruction to create a h~nzontal line 700. The instr~lctions from line 5 cnwards create the icons 701 to 706, along with tt~e hyperlinks associated with said icons reguired in order to allow subsequent pages ~o ~e rQc uested by a user.
Each icon is describecl by two iines, thus icon 701 is defined by lines 5 and 6, icsn 70~ is defined by lines 7 and 8, iGon 703 is defin~d by lines 10 and 11, icon 704 is defined by lines 12 ~nd 13, icon 705 is de~ned by lines 15 and 15 and icon 706 Is defined by lines 17 ar.d 18.
The vlewable ima~e is ~ffectively constructed on a line-by-line b~sis, 15 therefore the instructions effectiYely originate from lef~ ~o right, and th~
from Sop to bottom. After the sports icon, the word ~spor~, the electrical icon and the wording "electrical" h~ve been processe.l, it is.
necessary to create a new ~ine and paragraph breaks of this type ~re gener~ted by the p ta~, as present at lines 9, 14 and ~0. As previously 20 statedt each selecta~le icon is gener~ed from two lines, the first of ~hich, for example line 5, ~fines the hyporlink to ano~her page, by means o~ a URL to the seNer. The URL defined at line 5 woul~ be reco~ni~ed as a request ~or an on-line processing by the server.
Subsequent par~r~elers increment fronn 1000, to 1001, to 10~2, to ~5 1003, to 10Q4 and to 1~05, so as to unictuely identify the requ~sted pa~e.
The second line ~or e~ch entry, for example line ~, specifies the location of the graphl~al icon, thus th~ sports icon has been ~to~ecl in ~ flle identified as "sp~rtgif", while ~e electrical icon, ~efined at line 8, 30 has been stored as "elec.gi~', the comput~r equiprnent icon has been 2 ~ 76534 st~r~d as "comp.gif', the children ;con has been stored as "chlld.gir', the g~rdening icon has be~n stored as "ga~d.~i~' and the clothin~ icon has been stored as "~Ith.gi~'. The subsequent cocing specifies the Incation of the ioon withln the page so as ~o complete the o~ferall ~ormatting 5 requirementc From a user's point of view, the Image displ~yed on monitor 602 ~ppears iike a high-quality high-definition video ima~e, so as t~ ensure that ~ user Is not alienated by the system. However, from a transmi~sion point of ~iew. the imaye dlsplayed on monitor ~0~ is 10 g~nerated by the instructions shown in Figure 8. This recluires a sophis~icated le~el of processing to ~ pe~ormecl ~y the tra~smitting server and by the receivir~g ~rowser but the level of banclwidth required in order to pe~rm the transmission of information is substantially reduc~c3. The transmitted output signal con~ists of eight data bits for 15 each cf the ASCII ~h~racters represented in Fi~ure 8~
Although the ~andwidth rec uir~ment ~or transmitting ~n HT~IL file of t~?e type shown in Figure 8 is significantly redu~ed, when comp~red to video transmissions, it oan be apprsciated that the manual generation of a file of th~ type shown in Figur~ 8 would be extremely time 20 consuming, resulting in economi~ dimculti~s for anyone wishing to use the tecl,nc,logy for distributing information having a short shelf-life, having relalively low value or hav~ng both a short life and a low value.
In aGcordance with t~ e present system, it i~ possi~le for the inforrnation to be derived from conventional dztabases and for the HTM1 ~5 inst~u~tions to be generated on-th~. fly, as r~ cts ~re made by ~rowsing ciients. Thug, the generation of ;nstruGtion~ of the type shown in Fi~ure 8 ~comes an automated technical process performe~ in resporlse to strin~s of c~de generat~d functions stored at the ser~er.

~1 76534 HTML ou~put pages aro cre~ted by assembling portions of HTML
instr~tions, so as to ~reate a page suitable for generating outpuS
sign~ls, of the typo sho~vn in F~ure 8.
Each portion of outp~t HTML instructions i~ created by executing a p~rtioular function. This function is arranged to process data frorn a d~t~h~e or dat~bases in the form of ~iewable dala. This Yie~able data is then pro~essed under the control of the seleoted function in order to generate a portion of output HT~IL. A format function of this type may be consid~red as the small~st unit of instructions for producing a p~tion 10 of HTML oo~e.
The system as a ~hole includes a universai family s~t of all th~
available funeti~ns ~vhich may ~e used in order to senerate port;ons of HTML code. As the system develops, new functions may ~e add~d to the fam;ly set and it is expected that the HTML stan~ard will be 15 enh~nced, thereby recuirln~ additionai functions to be created. For any particular app1ication~ it is likely ~a~ not all of the possible ~nctions will be required, therefore fusncti~ns rnay be seiected ~rom the universal sets of ~11 available fun~tions. Select~ functions are known to both the browser and the seNen The br~wser issues URLs to the ~ver th3t are 20 understood by the serverS resulting in the req~ cl HTMsl page being transmittec~ back to the browser.
It is possi~le that a particular server may be corlfigured t~ run ~
plur~lity o~ applications and that s~id applications m3y requiro a different su~set of ror~n~tling funstions derived from a universal set of 25 a~/~ilable functJons. ln order to a~commodate this situation an in;ti~lisation process is performed by the on-line processing routines in order to as~emble the required formatting functi~ns in a w~y which enhanc~s on-line pr~essing speeds.
The fvr~ lling functions are arranged to generate sm~ll portlons 30 of HTML ~de, such that the universal set of f~",~dLIiny functions is minimised and so that any required ~utp~t p~ge may be generated by stringing formatting ~unctions together. The pr~processing initi~lisation procedur~s consist of identifyin~ strings of formathna f~nctions required to gener~te pa,~icular lines of HTML ~ode. Thus, a parti~ular llne of ItTML ~od~ is prod~cecl by s~quentially exea~ting a string of fo~matting functions and the pre-processing step consists of arranging such fun~tion strin~s such that ~ particular function string, arranged to generate a HTML page, may be q~lic}cly sought and executed during on-lttle operation.
C)ne function string ~Nill ~er~erate a par~icular line of HTML code.
In most applic~tions, not al~ lin~s will t~ke up the s~me forrn~t, therefore it is necessary to gener~te a plurality of function strin~s. These funetion strings are ~rr~ngecl in a string list, with an ind~xing pointer being provided so as to enable a particul~r function ~tring to be quickly "5 Identified fr~m the lis~ ~nd there~fter executed in order to generate the output ttTML instr~cffons.
Initiallsat,on step 501 is detailed in Figure 9. ~t step gO1 ~he system is effectlvety activated, which may con~ist o~ apply~n~ power to the system re~ulting in an ~utomatic "boot-up" or may consist of a ~0 selection being made to pe~r~ the particular task~ in preference to a previous unr~iated ~ask.
At step 902 the ~.e,dLi"~ system is initialis~d and the system conf~ured so ~s to facilitate connections to the Internet. This in;tialisation al~o includes all standard ~r~cesses to load peripher~l 2~ driYers etc., theroby placing the system in an operational condition.
~ t step ~03 com~entional procedures are exe~utecl in order to initialise the HTTP daemon, whereaf~er procedures are perfom~ed to initialise the on-line processing procedures ~ssociated ~ith the pr~sent "~.lil "~,l It.

At step 904 a question is asked as to whether another function string is to be generated which, on ~he first iteration, shoul~ be answered in the airi"nali~/e. At step 905 the f~nGtions r~quired to create ~he particular strin~, drawn from the universal set of avail~ble f~lnction~, 5 ~re identifl~d and at step 801~ the string it~elf is assemble~l by llsting the functlons ~r sequential processing with data derived from the database or data~ases. Thus, at step gO6 a complete funcUon string is creat~d.
At step gO7 the function string gene~ated at step ~06 is appended to the string list created for that part~cular ~pplication and at st~p 9V8 10 an ;n~exing reference is identifiecl within the list of strings. Thus, when a particu!ar call is ma~e for for"~alling si~nals, in the fo~n of an executable string of functions, the partiGular call identifies the index r~ferençe within the list of strings, resulting in the selected index being selected from the list and there~fter executed in ~ombination with the 15 referenced data.
~ hereaft~r, control is returned to step 904 thereby ailowin3 the nex~ function strin~3 to be processed. Eventual!y, all of the function strings w~ll have been c~ eated, append~d to the strir~ list and appropriately indexe~, resulting in the question asked at step 904 beir)g 20 answered in the negative and control being directed to step 90g At step 909 procedures are implemented to initialise ~tab~ses; so that data may be ac~essed from said datab~ses In aceordance with conventi~nal te~hniq~es.
The on-ilne file preparation step~, idenmied in Figure 5, are ~5 detailed in i~igure 10. At step 1001 the in~o~ URL, previously proc~ssed by the Hl~P daemon as Illustrated in ~igure 5 is buffered within a data stnucture defined by the on-line proces~in~ routines. The URL wili inciude an element identifying the data required, an ele m ent identifying the type of form~tting required, information rel~ting t~ the ~ 1 76534 user and a che~k sum, so as to reject URLs corrupted durin3 transmisston.
At step 1002 a question is ask~d as to whether the check sum is valid and if this ques~ion i9 answered in the negative, to the effect that 5 the check sum i~ inv~lid, control is directed to step 100g ~sultin~ in an error messaae being retumed to the browsing client device.
Similarly, a question is asked at step 1003 as to whether the user identi~cation is valid. 5n order for this question to be answered, it is n~essary for a call to be made to a user dat~base whioh wiil return an 10 indic~o~ as to whether the user c~n be identified from the datah~se.
If it is found that the user ID is not pr~sently available from the database, r~utines may be c~lled whi~h en~ble a user to be treated a~
a new user and open an appropriate a~co~nt while remaining on-line.
Thus, for ~x~mple, these routines m~y request the user to supply credit 15 card details etc. so that ~n aecount m~y be established i~nmediately.
In addition, the analysis of the ~ser ID at step 1003 allows additional ir,rorm~lion to ~ drawn from the ~ser database relating to th~t spesi~lc user. If ~ user ID has become inv~ , the ~ue~tion asked at step 1QO~ rnay ~e answer~d in the ne~ative, a~ain resulting in control 20 b~in~ ciirçct~d to step 100g and an error messa~e being directed to the browsing client.
After the check sum has been vaiidated and the user ID has b~en ~alidated, a ~uest;on is asked at step 1W4 as to whether the data identifier is valid. Identifiers for data are placed within established 25 formats, thus i~the server is unable to identify the clata being requested, an error message will be gener~ted at step 10~9. Simll~rly, an identifier for the formattin~ requested is validated at ~tep 1005, which may again result in an error Illessage being generated at step 1009.
~fter the data identifier and the format identifier have been 30 v~lidated at their respectiYe steps, the HTML page or payes ~dre generated at step 1006 with reference tQ the data identifier ~nd the form~t identifier. ~hereafter, with reference to the user ID, the pa~s are supplied back to the requestin~ browser via the nehNork.
After pages have been supplied b~ck to the br~wsing client, the 5 system is aware of this fact and therefore has inforrnation as to what ~s actua~y supp!ied to ~ user at a particular time. In some systems, this information may be oonsidered as haYina no valu~ ~nd tllerefore no further action is taken. H~wever, in al~ernative systems. partic~larly when proclucts are being sold, marketlng informatiGn may be c~nsi~ere~
10 a~ highly valuab3e, therefore pro~/ision is made ~r this inform~tion (i.e.
an indic~tion of what page~ were viewed at what particul~r tirn~) to be wnYten back to the user ~l~t~h~s~ at step 1W8. Thus, over timel illf~"nation will become available relating to us~r preferenc~s which, l~nder ~ome circ~;mstances, may ~e used to modify the operation of the 1 5 system.
It will be appr0ci~te~ that, d~ring normai opel~tion of the system various portions of fhe ~ta will ~e used on more than one occasion.
Thusl in a~ordance wi~h conventional techniq~es, d~ta r~3d from a d~t~b~se may be cached such that, on a second i~r~tlon, the da~a m~y 20 be more readlly available, ~hereby making it unneoe~sary to make an additional call to th~ user datab~se 1000. The system m~y be configured s~lch that data is held in cache for a pr~cletermlned period, say thirty minutes. Thus, if no use i~ made of the data within thirty m,nutes, the cz~he may be flushed such that, at any time, d3ta held in 25 the c~che represents a snapshot of users who ~re actuatly m~king use of ~he system.
A diagrammatic representation of proce~sing unit 301 along with its associated I~AM 303. when confi~ured to execute the on line processin~ instruGtions 40~ is shown in Figure 11 The hy-pertext 3~ tr~nsport protocol ~aem~n 40~ is shown diagramm~ti~ally on the le~ of Figure 11 and is ~rr~ng~d to supply URLs to an input URL buffer 1101 and to reoei~e output HTML d~ta from an output HTML buffer 1102.
The ~n-line processor 310 (prooessor 301 of Figur~ 3 ~rranged to execute the on-line pro~essing p~ocedures 405 o~ Figure 4) communi~tes with the user database 1000 as shown in Figure 10. In addition, the processor 301 is a~ranged to access strings from a string iist store 1 103, to acoess viewa~le tex~ from a text datab~se 1104 and to access viewa~le ~raphics from a graphics database 11~5 Each of the ~t2h~es ard ~e strin~ liSt store is relational, in that an index known ~o the pr~ce~sor 301 relate~ to a particular database ~ntry.
Thus, in respon~e to the processor 301 pointing to an inclex, the relafed data is retumet b~ck to the processor 301. Tht~s, the string list store 110~ includes a string index portion 1106 an~ the ac~uai string list portion 1107. Function strings are added to the string list portion 1107 at step 907 of Fiyure 9 with their reiated index reference being added to por~ion 1106 at step 908. The pro~essor 301 makes ~ request in terms of identifying a particular index reference, storec~ in po~tion 1106.
This index is related to a particular string he~d in pQrtion 1107. Thus, it is po~sible to adjust ~he relationship ~e~Neen indexes ~nd strings, thereby adjusting the way in which the ~ata is actually folmatl~d in resporlse to a p~rtioular req~lest.
Similarly, tex~ clata in a text database 1104 consists of th~ text data itself in porti~n 1108 and rel~ted text data indexes in portion 11~g.
Thus, da~a is selectecl from ~atabase 1104 by the or~line processor 30~
2~ issL~ing a partioular in~x to portion 110~. resulting in the related data, from portion 1108, beir~ returned to the on-line processor 301. Thus, it is the indioes that are known to the on-line processor 3û1 and the relationship b4~w~en in~ices and their related text data may be adjusted, so as to change the act~al d~ta th~t is returned in response 3~ to a parti~ular request being rnade.

The graphics database 1105 is also divided into re3at~d portions, consisting o~ an index portion 1 1 10 and a data portion 1 1 1 1. Thl~s, in response t~ ~he on-lin~ proce~or 301 identifying a particular referen~e within portion 1110, graphical data is read from portion 1111, As previously stated. a string read from portion 1107 consists o~
a string of executable functions. Thus, these functi~ns are supplied to the on-line processor 301 for exe~ution on said processor. Execution of a function read from the string list m~y result in HTML tags beir7g written directly t~ the output HTML buffer 1 102. Alternatively, execution of these fun~tions may result in a c~ll being made to the text database 1104 or to the graphics datab~s~ . In elther event, the call identifies an index, in portion 1109 or portion 11 1a, which in turn results In the related text data or gr~phics data belng supplied directly to the output HTML buffer 110~.
1~ Thus, the input URI will Identify particular types of formatting and particui~r type~ ~f data. The form~tting information for the URL will resul~ in particular ~unction strings being read from the string list ~tore 1103. Thereafter, these funetions are exe~uted, with reference to the dat~ ,t;riers, re~ulting in text d~t~ and graphics d~ta being read from the res~ive databases 1104 and 1 105. As the f~ln~.tions are executed, output HTML is written to the ~utput HTML buffer 1102 and after an identified set of fun~tions h~ve been executed, the H~ML
stored in out,out buffer 1102 is read, so as to supply the output llTML
si3nals to the Hl~P daemon 403.
In a~dition t~ usin~ the user d~ta~ase to oonfirm user ~alidity and to re~r~ ~ctions rn3d~ ~y the user (possibly for billing purpos~s) the on-line proGessor 301 may also make use of inror"~tion re~d from the user database in order to adjust the rel~tionship b~tween indexes (1106, 1109, 1110) and their associated function strings and data (1107, 11~8, 1111~. Thus~ it is possible for the processor t~ respond to a URL

in one ~f three ways. Firstly, in a standard m~de of operation, the particular output 11TML produced in response to a particular input URL
wili remain constant. The user database is mereiy used to check user valldity and to record user usage of the system. Thus, output clat~ i~ not 5 dependent upon user type and all users ~r~ supplied with the sarne data. However, adjustrnents rnay be m~de to the relationship within d~t~h~se~ over time, such that upclates or upgrades m~y be macle to take a~eount of the circumstances.
Thus. for arl in-home shopping s~tuation, t~e ~vailabiiity of goods 10 ~r,d changes in prices may be reflected in ~t~h~se relationships.
Simi~arly! in on-line journals and newspapers, the d~ta rel~tionship rn~y ~e adjusted in response to editorial ~ontrol, usually driven by news events. Thus, in a news environment, it is not necessary for ~ditors to c~eate new HTML doeuments if they wish to supply new doc~sments in 15 this format to users. All the f~r-"alling required to produ~e a pa~e in a p~rticular form is provi~ed within the formatting fu~ct.ions~ Thus, in order to update a news i~em, an editor is mereiy required to Ipdate infor" ,dtion contained in the datab~se (u~ually database 1~ 04) in accordance with conventional ~t~b~e techniques.
~0 As st~ted above. it is possible for the processor to respond to the UR~ in one of three possible ways. In a second enhanced mode of operation, it is possible for the user to identify information to the system as a means of expressing user preferences. Thus, in a home shopping ~viro"~ l for example, it is possi~le for a user to spe~ the 25 particular goods of interest. Thus, for examplel one user may only use the on-line shopping facility when shopping f~r gardening supplies. Th~
~ser may relay th,s information to the system, such that the systern will concentr~l~ on gar-J~ning products. Thus, on initiating the system, the first URL will result in a reference to gardening supplies, thereby 30 avoiding the first ~creen shown in ~igure 7, ~vhere the client has littie int~rest. The client will stil1 be able to access ~ll o~ the available ~nctions. For examp~e the sec~nd sGreen, containing predorninantly gardening prod~ct~, would include a link for "other areas" and on execu~ng thi~ i~utton ~e user ~ouid be effectively supp5i~d with the 6 higher level p~ge, there~y allowin~ his selections to branch out into the other areas o~ the on-line ca~alo~ue. In a more sophisticat~d system, the llser may only be inter~stedi in electrical equipn~ent ~nd sports equipment, such that a first screen would display the sports icon followe~ by particular types of sport, in co~ ination with the ~l~ctric~l 10 icon followed by particular electrical products. Thus, it is possible ~or the user to speci~ pref~r~n~es such that the system become~ more tail~r-rn~de and specific to that particular user.
Such ~n approach may also be used in news publications. For example, sonle users may be interested prc~ in~ntly in financial news 15 while others may ~e interest~d in sports news. Thus, with this inr~3rr"atioll programmed into the user database, the orcier in which p~g~s are supplied to a user may be adjust~i in accorclan~ with pr~f~re~1ces specified by the user. It will also be pcssible for users to speci~y w~ether the materiai is being re~d by children ~r by zdults and 20 f~r appropriate psge selections to be made. Pages desi~ned children ~uld ~e written using limited ~oGabularies and in~lude a higher ccncentration ~f hyperiinks, allowln~ children to rapidly access related information. In many situations~ some pages wouid ~e ~ppropria~e ~or both ty~s af users and ediitors would have control as to wnat is made 25 available at what levels. Similarly. higher ~harges cou~d be made for partlcular types of information ancl, gi~en information d6rived from the user ~atabas~, low priced pages or hi~h priced pages could be supplied as ~ppropriat~.
In a t~ird n~ocle of operation, identifiecl as a recursive mode of 3Q operation, it is not necess~ry for a user to identify their own pre~eren~es in ordc~ for ad~ustments to be made to the actual nature of pa~es r~turned to users. The system reco~ds a history of usags and there~fter analyses this Inforl~dlion in order to determine the relationship ~tween selection~ made by a browser and the actual data ret lmed back to the 5 customer. Thus, ~f~r a number of uses, it may become apparent that a user is only interested in clothinq and has shown very litffe i~terest in ~th~r pr~ducts available from the catalogue. On ~etecting ~his interest.
it will be possible for the system to present the clothing page ~s the first page sent to the user on initiation. Movlng on fr~m this, it m~y be 10 po~sible to identify particular types of clothing that are of interest to user. l'hus, for example, ~ user may be only interested in designer labels and having i~entified this inforrnation, it would be possible fot the systsm to give a higher priority to spe~ial of~ers available in this area.
Thus, informa~ion m~y be supp!ied to the system to the effect that 3 5 new limited edition has been produced which may be of particular rest to a minority of users of the system ~ region may be provided within an initial page to provide sp~cial informatlon or advertise-nents.
A particular type of information or adverti~ement supplied to this re~ion will depend upon customer history. Thus, if ;nformation has been 20 supp~ied to the effect tha~ a limited edition has ~ecome av~ilable, th8 system will automatically know which users are interested in obtaining it~ms of this type. ~hus, when this parti~ular sub-set of users log on to th~ system, the relevant information will ~e ~upplie~ back to them autom~tically. Similarly, an advertisement for a d~signer jacket, for 25 ex~mplel win not be sent to ~ user ~ho has preYious~y only shown an ~terest in computer equipment.
The sys~ern will ~e ¢apable of identifying sit~tions in ~Yhich pa~icular prociucts have been browsed for signi~icant periocs of time by u~ers. The ~ystem couici be prog(~rnln I to iden~ify this r~ct ~nd m~ke 30 an a~,ro,,riat~ modification when the user next lo~s on to the system.

For example. having d~tected that a parti~ular user has shown an inter~st in a par~i~ula. pro~uct, it may be assumed that a custorner is interested in buylng this product but, a3 yet, has not made a final decision The sys~em rnay use this informatlon in an attempt to persuade the client to make the purchase. Thus, the system may be programmed to offer discounts to c7ients such that, on the next use o~
the system, an ~dvertisen~ent appears ~Q the efrect that the product of interest h~s been reduced by a certain amount. Th~s, it is possible that users would perceive thls as an offer b~ing made to all clients, with the f~ct that they h~ve a particular interest in that product ~eing seen as a coinciden~e. ~l~arly this i~ not a coincidence and each us~r w~uld be offered ~omething which the system had detected as ~eing to their liking.
It can be appreciated that the possibilities are endless. This is all provided t~y the fa~t that the actual HTIVIL pages supplied back to users are generated ~'on-th~fly" by indexin~ locations within databases. The relation~hip be~e~n an index and an item may be adjusted so that the same instructions may be used to ~ccess different clata with on-going c~anges. Similarly, the system may id~ntify the particular usel concerned and, in response to this information, select an index which differs from the norrnal index selected. Alt~rnat~`vely, a particular index identified by a user may be treated by the ~ystem as a "wild c~rd", with an actual sele~t,on of an ind~x being made in response to information stored ab~lt the part clllar user.
Operations per~rmed by pro~essor 301, as il'ustrated in Figure 11, are detailed in Figure 12. At step 1201 a data strin3 index is identl~ied enabling the processor 301 to make a call to an appropriate database. At shp 1~02 a call to the database is ~nade, by issuing the string indexed to the appropriate database. resu~ting in th~ data string itself b~ing returned from the datab~se to the processor 301. ~hus, as shown in Figll,e 11, the read operation perforrned at step 1202 would resu~t in an inde~ ~ommand being issued from the processor 301 to :he indexed porti~n 11C9 ~f d~t~h~se 1104, whereafte~ the appropriæte data, from portion 1108, is retumed b~ck to the processor 301.
At step 12~3 a function string index is identified, from the form~tting information pre~ent in the U~L and at step ?~04 the irldexed function string is read from the string list store 1103 At step 1205 the function string re~d from the ~tring list store 1103 ~ executed, result~n~ in ~iTML code being written to the outps~t HlML b~ffe~ 1102, wher~ler, ~t step 1~06, a q~lestion is aske~ as to whether another function string ~as be~n identified. I~ this question is answered in the affirmative, control is returned to st~p 1201 and t~e procedures identified above are repeated. Eventually, the question asked at ~tep 1206 wi~l be answered in the negative, resulting in the completion of procedure~ within step 1006.
Step 1~05, for the ex~çution of a string function, is exp3nded in Figure 13. A string of functions has been read from the string list store and this string of functions Is executed, sequentially function by function, at step 1~05.
At step 1301 the next function, i.e. the firs~ function on the first itera~ion, is read from the function strirly. At st~,~ 13~2 this p~ cular fun~ion is executed, resulting in a unit of HTML code being written ~o the o~tput tllML buffer 1102 at step 1303. At step 13W a q~estion is asked as to whether a function includes a further functional step and if an~wQr~:d in the amrmative, control is returnecl to step 1302 for the nex~
funçtion step to be executed. Thu~, a funcUcinal step may be considered as the sm~llest portion of a function that rçsults in a write to the HTML buffer.
Af~er all the exe~utable steps of the function have beeri completed, the question asked at step 1304 will be answer~d ir the ne~ative, resulting in a question being asked at st~p 1305 as to whether another function is present In the strin~. If another function is present in the s~ring, the question asked at step 1305 will be answered in the arri,~ e, thereby returning control to st~p 1301. Thus, steps 1301, 1302 1303 and 1304 are repeateci in order to execute the next executable function within the string r~ad from the string ~ist store.
Eventually, all of the f~nctions making up the strinq will have been executed, resultin~ in the question asked at step 1305 ~eing an~wer~d in the negative so as to comp~ete pro~ed~res within step 1205.
The functions exe~l~ted over steps t3û2 to 1304 will have ~een created so as to generate the parti~ular HTML c~de require~. An example Gf a fun~tion i~ ~hown in Figu~e ~i4 and it should ~e appreciated that simila. techniques are employed in order to generate all of the avai!able types of HTML code. the fun~tion shown in Figure 14, that may be considered as being exe~uted at step 1303 of Figure 1~, is used to generate the fir~t line of the exarnple HTML code shown in Figure 8 A first functional step, ~hown as step 1401, writes the tags "CHEAD~TlTL~" as the st~rt of line 1. Th~se tags are written to the output HTML buffer ~t step 1303 an~ thereafter the q~estion asked at step 1304 would ~e answered in ~e ~ri~ dti~e, res~l!ting in the next functional step ~eing executed at step 1302. In the example shown in Figure 14, this would consist of the execution ~f step 1402, consistin3 ~5 o~ a write to the output HTML buffer of tt~e view~ble data ~Home ~hopper". This parti~ular portion of the code is derived by makin~ a call to the text d?t~h~se. Thus, the write instru~tion consists of a d~t~h~se index. Da~abase 1104 is identified. along with index position 001.
Th~us, it is known that at inc-iex positi~n OQ1 in the text dat3base 1104 the title of the fir~t p~ge has ~een stored. Thus, as part o~ an editing procedure it may be decided that the title should be changed to "Shopping at Hom~" for exarnple. When a change of this type is required, it is only necessary for an editor to make a change to the d~tabase enby stored at index p~sition 001 in d~P~e 1104 This ~an 5 be achieved using conventional database te~hniques, without any spe~ia3ist knowledg~ required of the HTML language us~d to transmit the information over th~ Intemet. The operation of the system is unaffected by this change of title and the proc~dure sho~n at step 1402 will execute as required, irrespe~tive of the nature of the ~ctu~l tit~e text 10 contained within the d~t~b~se.
Thus, at step 1402 datab~se 1104 is identified, ~n address to that d~t~h~se is n~ade in th~ form of identi~ying index 001 ~nd text is returned to the processor 301. This text is then suppllec~ to the nex location o~ the output HTML buffer 1102 ~t step 1303 and control is 15 directed to step 1304, where the question is again asked as to whether another functional step is present. Again, this questTon will be answered in the a~i.",~ti"e, resulting in control being returned to step 130~ so that the next h~nctional step may be executed. As shown in Fi~ure 14, the rext executable step consists of step 1403 whi~h will resu!t in ~o 'lcrrlTLE~HEAD~ being written to ~he output HTML ~uffer 11û2 at step 1303. Again the question will be asked at step 1304 as t~ whe~her another ~n~tional step is present and on this oc~sion the question will be answered in the negative, resulting in control being dire~ted to step 1 305.
~5 Thus, it can be seen that a particular function l~as resùlted inthree writing op~rations to the GUtpUt HTML buffer in the forrn of ~ tag.
view~bte text o~ined from ~ da~base. followed by another HTML tag.
This prooess is re,~eat~d for each of the ~unctions contained w~thin the funGtion strin~ until the hull page of HTML code has been gene~ted and written to the HTML ~uffer 1102. Signals from the HTML buffer 1102 ar~ than supplied to the HTTPD 403 which in turn supplies the signals to the browsing client via the Internet.
The clatabases for storin~ text ~nd graphi~s are o~ conventional types, having mechanisms for requests to be made ~or inforn~ation to be 5 supplied. In particular, requests to d~tah~ses are made l~sing t~e s~ru~tured query language (SQL) and d~ta is obtained from the d3tab~ses by gPnerating an SQL en~iry.

Claims (17)

1. A method of serving output signals from a serving device to a plurality of browsing devices connected to a network, wherein said output signals represent commands executable by a browsing device so as to display viewable data in accordance with a specified page format; said method comprising steps of:
identifying requests from browsing devices that define a request for specified viewable data, said request including formatting type identification data;
maintaining a plurality of formatting types of data defining respectively corresponding predetermined formats for portions of said viewable data;
storing content data representing said viewable data;
selecting a specific part of said content data representing specific viewable data;
selecting a specific one of said types of formatting data in response to said formatting type identification data;
processing said content data and said formatting types of data so as to combine said selected part of said content data with said specific one of said types of formatting data, and for outputting processed viewable data with executable instructions; and supplying output signals to the requesting browsing device derived from said output processed data, in which said output signals represent commands executable by a browsing device so as to display said specific viewable data in accordance with a first specified page format when a first type of formatting data is selected and in a second specified page format when a second type of formatting data is selected.

2. A method of serving output signals from a serving device to a plurality of browsing devices connected to a network, wherein said output signals represent HTML (hypertext mark-up language) data executable by a browsing device so as to display viewable data in accordance with a specified page format; said method comprising:
identifying requests from browsing devices that define a request for specified viewable data, said request including formatting type identification data;
maintaining a plurality of formatting types of data defining respectively corresponding predetermined formats for portions of said viewable data;
storing content data representing said viewable data, said content data including graphics data;
selecting a specific part of said content data representing specific viewable data;
selecting a specific one of said types of formatting data in response to said formatting type identification data;
processing said content data and said formatting types of data so as to combine said selected part of said content data with said specific one of said types of formatting data, and for outputting processed data in the form of hypertext mark-up language data; and supplying output signals to the requesting browsing device derived from said hypertext mark-up language data; and in which said output signals represent hypertext mark-up language data executable by a browsing device so as to display said specific viewable data in accordance with a first specified page format when a first type of formatting data is selected and in a second specified page format when a second type for formatting data is selected.

3. A serving device for serving output signals to a plurality of browsing devices connected to a network, wherein said output signals represent commands executable by a browsing device so as to display viewable data in accordance with a specified page format, said serving device comprising:
means for identifying requests from browsing devices that define a request for specified viewable data, said request including formatting type identification data;
means for storing a plurality of formatting types of data defining respectively corresponding predetermined formats for portions of said viewable data;
means for storing content data representing said viewable data;
means for selecting a specific part of said content data representing specific viewable data;
means for selecting a specific one of said types of formatting data in response to said formatting type identification data;
means for processing said read content data and said formatting types of data so as to combine said selected part of said content data with said specific one of said types of formatting data, and for outputting processed data in the form of executable instructions; and means for supplying output signals to the requesting browsing device derived from said output processed data, in which said output signals represent commands executable by a browsing device so as to display said specific viewable data in accordance with a first specified page format when a first type of formatting data is selected and in a second specified page format when a second type of formatting data is selected.

4. A serving device as in claim 1, wherein said content data is stored in a first database and said types of formatting data is stored in a second database such that said viewable data is updateable by updating said content data only.

5. Apparatus as in claim 1, wherein output signals sent to a browsing client are derived in dependence upon an indication of the identity of the user.

6. Apparatus as in claim 5, wherein output signals sent to a browsing client are derived in dependence upon a stored indication of previous user selections.

7. Apparatus according to claim 1, wherein:
a request from a browsing client takes the form of a resource location, a first database is accessed in response to this resource location to identify a function, said function retrieves viewable data from a second database, and said viewable data is combined with mark-up language codes to produce said executable instructions.

8. A serving device as in claim 1, wherein:
said serving device further comprises a user database storing information relating to each of a plurality of users, said request includes data relating to a user identity, said serving device determines whether the user identity is stored on said user database, and when said user identity is stored on said user database said serving device serves output signals in dependence of stored information relating to said user identity.

9. A serving device as in claim 8, wherein said stored information relating to said user identity relates to previous requests from said user.

10. A serving device as in claim 9, wherein a particular region is provided within a page to provide advertisements and a particular type of advertisement supplied to said region depends on said previous requests from said user.

11. A serving device as in claim 1, wherein:
said request includes data relating to a user identity;
said content data is stored in a content database having an index portion containing a plurality of indexes and a content data portion containing a plurality of database entries, such that said database entries have related indices; and said serving device further comprises a user database for storing information relating to each of a plurality of users, the relationship between said indexes and said database entries being adjustable in response to information read from said user database, whereby said specific part of said content data is selected in response said user identity.

12. A serving device for serving output signals to a plurality of browsing devices connected to a network, wherein said output signals represent HTML (hypertext mark-up language) data executable by a browsing device so as to display viewable data in accordance with a specified page format, said serving device comprising:
means for identifying requests from browsing devices that define a request for specified viewable data, said request including formatting type identification data;
means for storing a plurality of formatting types of data defining predetermined formats for portions of said viewable data;
means for storing a plurality of formatting types of data defining predetermined formats for portions of said viewable data;
means for selecting a specific part of said content data representing specific viewable data;
means for selecting a specific one of said types of formatting data in response to said formatting type identification data;
means for processing said content data and said formatting types of data so as to combine said selected part of said content data with said specific one of said types of formatting data, and for outputting processed data in the form of HTML data; and means for supplying output signals to the requesting browsing device derived from said HTML data, in which said output signals represent HTML data executable by a browsing device so as to display said specific viewable data in accordance with a first specified page format when a first type of formatting data is selected and in a second specified page format when a second type of formatting data is selected.

13. A serving device as in claim 12, wherein said content data is stored in a first database and said types of formatting data is stored in a second data base such that said viewable data is updateable by updating said content data only.

14. A serving device as in claim 12, wherein:
said serving device further comprises a user database storing information relating to each of a plurality of users, request includes data relating to a user identity, said serving device determines whether the user identity is stored on said user database, and when said user identity is stored on said user database said serving device serves output signals in dependence of stored information relating to said user identity.

15. A serving device as in claim 14, wherein said stored information relating to said user identity relates to previous requests from said user.

16. A serving device as in claim 15, wherein a particular region is provided within a page to provide advertisements and a particular type of advertisement supplied to said region depends on said previous requests from said user.

17. A serving device as in claim 12, wherein:
said request includes data relating to a user identity;
said content data is stored in a content database having an index portion containing a plurality of indexes and a content data portion containing a plurality of database entries, such that said database entries have related indices; and said serving device further comprises a user database for storing information relating to each of a plurality of users, the relationship between said indexes and said database entries being adjustable in response to information read from said user database, whereby said specific part of said content data is selected in response said user identity.