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A LEVEL INFORMATION TECHNOLOGY REVISION NOTESUser SupportMethods of User SupportA help desk?A dedicated telephone number/email address/electronic link?The user can communicate directly with a person trained in support Who may be able to control the user’s computer remotely?Who may have access to a database of problems and solutionsWho will talk the user through the systemA user groupA formal/dedicated body of enthusiasts/end users of a particular system/software package?Who communicate via an electronic forum/bulletin board/series of meetings?The user can post their problem/query?Or start a thread?And get a response from users with the same problemsUser Group HelpThe user group enables its members to share knowledge/exchange ideas about the ICT application?The user group will have an online forum/bulletin board/publish e-bulletins/produce newsletters and other publications ?The employees could check posts/threads/blogsTo see if an answer to their problem already existsOr create a new post or thread/blog?And receive replies/feedback from other users of the application Health IssuesHealth Issues from ICTRepetitive Strain InjuryPain or numbness in muscles / nerves / tendons / ligaments Caused by constant repetitive / forceful activities when using ICT equipmentSuch as secretary using a keyboard for prolonged periodsMinimised byUsing ergonomically designed devices e.g. split keyboardOr taking regular breaks from using ICT equipmentPosture / Skeletal problemsBack pain / disc problems / postural stress / sciatica Caused by sitting for long periods in an uncomfortable / unnatural sitting positionMinimised byUsing adjustable chairs / 5 wheeled chairsOver exposure to the EMF frequencies emitted by CRT’sCan lead to reduced productivity / fatigue / sleeplessness / skin problems / headachesMinimised byUsing a screen shieldEyestrain problemsCaused by an unnatural view positione.g. small fonts, glaring coloursMinimised byUsing an anti-glare screenPrecautions to minimise eyestrainBlinking regularlyAdjusting the screen heightAdjusting the brightness / contrastRegular eye testsLarger monitorsAdequate lightning conditionsHealth Problems that may affect computer users and how they can be minimisedRSIThis occurs in the upper back/neck/shoulder regions/arms/elbows/ wrists/hands/fingers?Symptoms range from numbness/restricted movement to chronic painRemedy?Take regular breaks every half hour from working at your computer?Regularly stretch to relax the body?Use footrests, wrist rests and document holders?Use an ergonomically designed workstation/keyboard/chair Carpal tunnel syndromeThis occurs when a nerve is pinched/compressed in the wrist?The symptoms are pain, numbness, tingling/weakness in the wrist Remedy?Take regular breaks every half hour from working at your computer?Wear a wrist brace/splint?Have a cortisone injection/surgeryUlnar neuritisThis affects the back of the inside of the elbow?The symptoms are tingling/pain in the fingers/elbow/funny bone Remedy?Use an adjustable seat?Avoid putting the elbows on the desktop Use a wrist supportBackacheThis affects the muscles in the back?The symptoms are mild/severe pain in the back Remedy?Maintain a natural posture while using the computer Have adequate lower back support/footrests?Avoid sitting in the same position for extended periods An ergonomically designed workstationRadiation damage?From rays from the screenWhich can affect the whole body Remedy?Use an anti-radiation screenVideo ConferencingHardware resources required for video conferencing:Video WebcamMicrophoneSpeakersMonitorBroadband ConnectionModemBenefits of video conferencing to train users:Travelling is reduced (cost/time)Trainees can participate from their normal work placesTrainees throughout the country can be trainedReduction in costs / time / environmental impactSupports multimediaTrainees can observe what the tutor / trainer is doingInteractiveTrainees can communicate directly with the trainerTrainees can be observed using the systemTraining sessions can be recorded and repeated laterCASE ToolsCASE ToolsAutomates / supports all / many project management activitiesFor the planning / monitoring / controlling of the project’s schedule and costSuch as identifying / assigning / sequencing tasks and resourcesProducing CPA / PERT charts / Gantt chartsIn electronic formCan be saved / reusedUsing templates / drawing toolsMay perform validationSupports electronic communication within the project teamE.g. via email / forumsImproved software quality?CASE tools such as DFD generators provide automatic validationEnsuring that validation is carried out accurately/completelyReducing the risk of errors/eliminating human error?Code is produced automatically by a code generator?And should be error-free/free from human error?Code will be optimised?So it will be efficient/execute faster?A project management tool supports the organisation of a software projectReducing the risk of the system not meeting its objectivesReduced development time?Code is produced at electronic speeds?Which is faster than a human programmer could?Code generators produce consistent/standard code?Which requires less testing?Templates such as DFD shapes can be ‘dragged and dropped’/ reusedWithout having to be drawn from scratch?Graphics tools such as DFD generators automatically populate the data dictionary?So this stage does not have to be performed by the designer/ developer?CASE tools produce electronic output?Which can be saved and re-used for other systems?A project management tool automates CPA/Gantt charts/timelinesEnsuring development will progress to scheduleBenefits of using a CASE tool for project managementReduced development timeThe PM CASE tool automatically performs tasks such as critical path analysisPerforms tasks such as CPA faster than a humanStandard templates / previous PM data can be re-usedImproved quality / increased accuracyThe PM CASE tool automatically validates / checks processes e.g. Gantt chart productionDoes this consistently / eliminates human errorThe PM CASE tool provides the PM with better quality informationEnables the PM to make better decisions such as responding to risks / bottlenecksOther types of CASE ToolGraphics toolAssists / automates the modeling of the systemBy creating and maintaining DFDs, ERDsAutomatic validation of DFD levels / ERD relationshipsAutomatic population of the data dictionaryCode generating toolAssists / automates the production of program code / interface codeFrom formal program specificationsCode is optimizedInterface generating toolAssists / automates the production of code for the user interfaceFrom design of IO objects (buttons / text boxes etc)Data dictionary generatorAutomatically populates the DDWith processes / entities / attributesAutomatically validates the DDThe developer can add documentation / annotationUser InterfacesGraphical User Interface (GUI)Not text basedUses windows / icons / menus / pointersPull down menusButtonsScroll barsWizardsMouseMultimedia ElementsAudio / sound clips, video clipsWYSIWYGMain features of a Natural Language InterfaceAllows user to interact using written or spoken language instead of computer language and commandsVerbs or phrases usedTo instigate functionalitySuch as creating, selecting, modifying dataSounds are stored in a databaseUser input compared with theseSpeech recognition software is usedDrawbacks of Natural Language InterfacesIt can be difficult to implement effectively / accuratelyDue to unpredictability of natural languageAnd ambiguity of natural languageOr variations in a person’s voice patternsIt can be time consuming to initialise / calibrate the systemThe user may have to keep repeating words / phrases until they are recognisedIt has to be calibrate for one user at a time / it may only work with a single userMay not function accurately in a noisy environmentCommands may be misunderstood due to background soundsMain features of a Command Line InterfaceThere is a finite list of commandsEach command is a short word e.g. PRINTEach command is typed at a promptSome commands have parameters or switchesWhy an experienced user may prefer a CLI to a NLIExperienced user will have memorized all the commandsTherefore a CLI is a very direct method / requires minimal keyboard entryInput to a NLI is relatively slow and can be verboseProne to error due to mispronunciations / extraneous noiseWhy a touch screen interface is suitableInterface does not require keyboard skillsTherefore can be used by members of the public / inexperienced usersThe interface is intuitiveActions / menu options are chosen by pressing the appropriate icon / part of the screen The interface is durableNo moving parts e.g. keys on a keyboardIt can be kept clean / is hygienicThe options for businesses can lend themselves to imagesWhich can be used as iconsThese icons can be changed dynamicallyTo accommodate users not speaking local language for exampleGUI: Opening ApplicationsAn icon or shortcut representing the applicationCan be clicked / double clickedNavigate to the name of the applicationIn the menu / submenuHighlight / click itUse a hot key / shortcut / function keyCombination of specific keysBy pressing a special keyHuman Computer InteractionFactors influencing Human Interaction with Computer SystemsErgonomic factorsConcerns the design ofThe general working environmentInput devicese.g. adjustable chairs / split keyboardsThe design of general office furnitureAdjustable chairsMinimise the risk of back painThe design of computer equipmentSuch as split keyboardsMinimise the risk of RSIPsychological factorsConcerns how humans learn thingsHuman perceptione.g. short and long term memory / intuitionThis includes how humans retain and recall information?Including long-term/short-term memoryAnd human perception?In which past experiences can influence how users perceive objectsThe memory load on the user should be kept to a minimum/cognitive overload should be avoided?Examples: the use of short menus or icons/use of standard interfacesThe use of metaphors/suitable colour schemesThe use of colours to strengthen or weaken information such as ‘green for go’The use of common interfacesReduces the time taken to adapt to new systemsReduces the need for trainingFacilities can be provided for inexperienced usersGUIWIMPOn-line / context sensitive helpHuman PerceptionPast experience can influence how humans perceive objectsUse of metaphors colour association / sound associationExample:Red for danger, use of muted colours to encourage calmHuman MemoryHow humans store, retain, recall informationLong term memory versus short term memoryExample:Limit to menu depths / provision of standard interfacesInteractive DVDThe content can include multimedia elementsSuch as video clips to show the user how to perform a taskSound for verbal instructionsThe content can be access in a non-sequential orderThe user can select different options / choose a personal path through the material Ergonomic Peripherals: Keyboard ExampleAn ergonomic keyboard is specifically designedTo be physically comfortable/natural to use?An ergonomic keyboard may be split in two/have two parts at an angle With an integrated/separate/adjustable wrist or palm supportSome ergonomic keyboards have vertically aligned keys Enabling the user to type with their hands held vertically with ‘thumbs up’?An ergonomic keyboard enables a more natural posture And requires less finger effort/reduces key reach Which can minimize fatigue/RSI/Carpal Tunnel syndromeAnd boost productivityCAD / CAMComputer Aided Design (CAD)Computer technology is used in the design of objects / shapesObjects can be viewed in 3DTechniques such as surface rendering can be appliedAn object may be rotated in three dimensionsViewed from any angleViewed from different distancesCalculations can be performed automaticallyStandard objects shapes / templates can be usedDesigns can be reused / editedComputer Aided Manufacture (CAM)Specialised computers are used to control and monitor tools / machinery in manufacturing The steps in the manufacturing process are built into a programThe program may be the output from a CAD stageA computer can control a series of robotsMoving the product from machine to machineAs each stage in the manufacturing process is completedCNC technology can be usede.g. to control lathesSome CAM systems can automate tasks such as parts ordering / scheduling / tool replacementSoftware / System DevelopmentPrototype DevelopingA first cut / non-functional model is createdEvaluated by the userUser provides feedbackFeedback goes to the analyst / developerAn improved / refined model can be createdThe prototype may evolve in the final system / evolutionary prototypingThe prototype may be discarded when the system objectives have been established / throwaway prototypingPrototypingA first-cut solution/model is developed?This may be a non-functioning front end/dummy user interface?This is evaluated by the user?Who provides feedback to the developer?The model is repeatedly refined and evaluated?The user interface is modified?Functionality is added?The iteration stops when the user is satisfied with the system?i.e. evolutionary prototyping?Or when the user requirements have been established?And the system can then be developed using the waterfall methodi.e. throwaway prototypingWaterfall ModelThere is a sequence of distinct stagesExample:AnalysisDesignTestingEvaluationOne stage must be completed before next stage commencesDeliverables are produced at the end of each stageExample:System specification at the end of the analysis stageIf an error is found during one stageA previous stage may have to be reworkedEnd User Involvement during the Waterfall ModelThe users will be involved in acceptance testingWhere they use the system in a realistic environmentUsing real data / volumes of dataTo ensure the system meets its objectivesBy providing feedback to the developersThe user will be involved in the system review / maintenanceWhen the system has been in use for a short timeBy providing feedback to the developersAbout errors discoveredAnd enhancements requiredRapid Application Development (RAD)An iterative development process (continuous/cyclical)?A preliminary data model is developedAnd a prototype/user interface developedProviding the business processing/functionality?The prototype helps the analyst and users to verify the requirementsAnd to refine the data modelAnd implement the required processing?There are strict deadlines set for each refinement?User requirements/system functionality are prioritised/categorizedAs essential/non essential?Formal workshops are scheduled between the developer and users The JAD methodology is often used?CASE tools are usually usedSoftware MaintenancePerfective maintenanceThe system is working correctlyImprovements are implementedSuch as reduced access times / greater accuracyAdaptive maintenance Additional functionality is addedSuch as new user requirementsOr requirements required by external factors such as new legislationCorrective maintenanceFact Finding Methods during AnalysisObservationThe users of the system are observed as they carry out their daily tasksInterviewThe users respond to spoken questions on a one-to-one basisThe interview may be structured or unstructuredDocument InspectionSamples of orders / invoices / reports are examinedTo identify inputs and outputsQuestionnaireUsers complete a set of pre-determined questionsWhich may be open or closedTechnical Document UsageThe technical descriptions of the systemSuch as user requirements / system specification / DFDs / ERDs / module specifications / code listings / data dictionaryWill be used to identify errors / enhancementsModified as necessaryThe test plan / test dataWill be used to retest the systemTo check that errors have been corrected / changes work as expectedSections in User DocumentationHelp / FAQs / TutorialsInstallation instructionsHW & SW configurationUser guide / instructionsContents of a typical User GuideMain ContentsThe purpose of the systemContains the system objectivesDescribes the functions provided by the systemThe system configurationSpecifies the minimum:Hardware requiredSoftware requiredInstallation guideImplementation instructionsDescribes how to install the softwareAs well as load / create initial data filesOperating instructionsDescribes how to operate / navigate through the systemUsing step by step examples / screenshotsFor example, printing a reportTrouble shooting / help sectionDescribes common problems and how to fix themUsing FAQS as an exampleAdvantages of using an on-line user guide rather than a hard copyIt can incorporate multimedia elements such as video clips/sound clips/hyperlinks ?It can be interactive/the user can use hyper links to navigate through the guide?It can be context sensitive/provide help on what the user is currently doing ?It can provide a search facility/search engine/the user can search for specific topics by name/key words?As it is electronic, it can be kept up to date more effectively by updating a master copy ?Multiple users can access a single copy of the on-line guide?Greater accessibility – the user can adjust screen or text sizes/zoom in and out Obtaining New SoftwareOff the shelfPurchase standard software off the shelf from a computer store / online retailerStandard packages availableIn houseDevelop the software in-house using software specialists / software departmentSome companies may not have required expertiseOutsourcingOutsource the development of the software to a third partySoftware development companyCompanies can have specialist software designed specifically for their needsUnit TestingTest dataNormal dataLies within the permissible rangeE.g. 2 for a month numberExtreme dataLies on the boundaryE.g. 12 for a month numberErroneous dataShould not normally occurE.g. 13 for a month numberAcceptance TestingPerformed when the software is ready to be released / handed over to the client / users / after application testingIntended to give the end users the confidence that the software meets their requirementsA group representing the end users test the applicationUsing real world scenarios / dataThe users report back / provide feedback on any problemsEventually, users sign off the software / complete the contractAlpha TestingPerformed by the developerThe system is tested against the system / module specificationsIncludes module testing / integration testing / system testingTest schedule / plan producedTest data is usedBeta TestingPerformed after alpha testingSystem given to selected groups of potential usersKnown as pre-releasing testing For use in a realistic environmentWith real data / real volumes of dataThe users evaluate the system Provide feedback to the developerAssociations and Societies Benefits of joining the Association for Computing Machinery (ACM)Membership of the world’s largest educational and scientific societySpecifically for computing professionalsAccess to a wide range of resources Publications/on-line books/searchable digital library/newsletters Access to special interest groups?Attending conferences/accessing specialist publications/activities Access to professional development coursesAnd career adviceContact with online forum groups?Communicating with fellow professionals throughout the world Benefits of joining the Association for Computing Machinery (ACM)Members have access to the world’s largest digital library?Of computer/ICT literature, publications, online books, journalsThe ACM enables members to contact fellow members?Via newsletters/at conferences/seminars/courses/special interest groupsThe ACM provides career guidance/a Career and Job Centre section Which is an electronic meeting place for job seekers and employers in the computing/IT industry?They provide online coursesEnabling members to keep abreast of the latest development in ICT They provide accreditation for qualifications/coursesBritish Computer Society (BCS)Role of the BCSThe Chartered Institute for IT / represents IT & Computing specialists / the IT sectorPromotes wider social, economic progress through the advancement of IT science and practiceBrings together industry, academics, practitioners, government To share knowledgePromote new thinkingInform the design of new curriculaShape public policyInform the publicProfessional AdvantagesContact with other IT professionalsOver 70,000 members (practitioners, businesses, academics, students) in the UK and worldwideDelivers a range of professional development tools for practitionersOffers a range of widely recognised professional and end-user qualificationsFor beginnersHome usersProfessionalsValidates a range of qualificationsMembers can keep up to date with developments in ITMembers can avail of up to date training in IT tools / techniques / CASE toolsAudit TrailsAudit Trail ActivitiesThe terminal where each user is logged onThe identity of logged on usersThe resources accessed by each userThe number of unsuccessful attempts at logging on to an accountThe time during which user is logged onAudit SoftwareAudit trail / log can help identify who was responsible For unauthorised modification of software for exampleRecords who was logged on / username / IP addressAt which stationsThe log on / off timesAll access to data files / read / write optionsNetworks & DataData ConsistencyA particular attribute has only one value at a particular time / throughout the databaseA change to a data value is implemented throughout the database Because it is held in only one tableData IntegrityRefers to the validity / correctness / accuracy of dataWhich can be affected by input errorsAnd processing errorsMinimised by data verification / validationData InconsistencyAn attribute / field stored more than once does not have the same value throughout Data RedundancyNon-key dataStored more than once in the databaseE.g. titles of projects / names of clients / programmesThis increases the memory needed to hold the databaseIncreases data retrieval timesImpacts on data integrity / data consistencyData IndependenceData is kept separateFrom programs / software which use / processes itHow data can be stored on a network and kept secureThe use of User IDs and passwordsEach authorized user is allocated a unique User IDAnd a default passwordWhich the user can changeA valid User ID and password are required to log to onThe use of access rights / levelsEach user of the network is allocated specific rights to data filesExamples include read only / read and writeThe access levels are maintained in an electronic tableAutomatically checked when a user tries to access a data fileUse a firewallThis monitors traffic into the networkTraffic must comply with the security policyDifferent levels of security can be setIf the policy is not met, access is deniedHow data can be transmitted on a network and kept secure Data encryptionData is coded before transmissionUsing a special algorithm / keyOn receipt data is decodedUsing the same algorithm / keyIntercepted data is meaningless without the keyAnti-Virus SoftwareIt automaticallyChecks / scans all transmitted files / programs / softwareComing into the networkVia email / attachments / the Internet / portable devicesAgainst a databaseOf known viruses / signaturesWhich is updates to keep track of new viruses Blocks / deletes anything identified as malicious to data E.g. spywareDisinfects files / remove viruses from filesSuspicious software may be quarantined / run in isolationA report detailing identified viruses is produced FirewallMonitors / checks / analyses / filters all traffic / data / communicationEntering the networkOr leaving the networkBlocks / denies any messagesWhich does not meet specified criteria / security policy / settings / rulesWill permit access to legitimate communicationsIt may be part of a proxy serverA report detailing unauthorised attempts is producedData EncryptionData is transferredBy the application of a keyBefore data transmissionOn receipt the data is decryptedUsing the appropriate decryption keyIntercepted data is meaningless without the keyInternet Data Security ThreatsAttack from viruses / spywareAttached to emails or other files / from infected sites / from non-secure sitesLeading to data loss / modificationUnauthorised external accessFrom programmers / hackersLeading to unauthorised use of data / fraudulent use of data / corruption of data / deletion of filesClient Server NetworkAt least one controlling / dedicated / host serverWhich is a high capacity / high speed computer with a large hard disk capacityWhich serves / handles requestsFrom many clients / the other nodes on the network / clients initiate requestsFor resources / servicesSuch as data / files / software / email / web access / storage / peripheralsThe server provides communication links / controls access / securityPeer-to-Peer NetworkThere is no server / controlling computerAll nodes / computers are of equal statusNodes are both supplies and consumers of resourcesEach node makes of its resources available to the other nodesA node can request a resource that it needsResources include processing time, data storage, disk storage, bandwidth, and printersEach node is in charge of its own security / administrationDecided which other nodes get access to its resourcesWireless LANThis connects computers together within a small geographical area?All network computers/stations/devices are wireless enabledEquipped with wireless network interface cards (WNIC)/dongle?Access points act as base stations/hubs for the wireless networkWhich transmit and receive radio signals for stations to communicate with Wireless devices can be laptops, PDAs, IP phones or fixed desktops /workstationsParity CheckingAn extra bit is added to a group of bits / byte / block of dataMaking the number of 1s odd or evenThe bit is transmitted as part of dataThe parity is checked on receiptIf the data’s parity bit is incorrectAn error has occurred / a bit or bits have ‘flipped’Only an odd number of ‘flips’ will be detectedError Correction:With simple parity checking, it cannot determine which bits have flippedThe data will have to be re-transmittedWith latitudinal and longitudinal parity checks / block parity checksIf one bit is transmitted incorrectly the error can be located and correctedChecksumCalculated by adding together all the bytes / applying an algorithmIn / to a block of dataOr 256 bytes for exampleThe checksum is recalculatedAfter data transmissionIf the checksum is incorrect, the data is very likely to be an errorSome types of checksum may automatically correct the errorEcho CheckingThe receiving device sends the received dataBack to the transmitting deviceThe transmitting device can compare this data with the originalAnd make corrections as appropriate / retransmit the dataCommunication StandardsTo enable different hardware devices / computers / software / information systemsTo pass data / messages to one another coherently / securely / compatibly Using agreed formats / rules / error handling /speeds Open Systems Interconnection (OSI) Developed as part of the Open Systems Interconnection initiative By the International Organization for Standardization (ISO)/ANSI The OSI model consists of an abstract / basic model of networkingA set of specific protocolsIt defines a layered protocol / there are seven layersEach later deals with specific functionality / each later is independent of the othersControl is passed from one layer to the nextEach layer interacts directly only with the later immediately beneath itProvides facilities for use by the layer above itP D N T S P AA PromptA prompt is a message / hint / place marker / indicates the point or purpose of inputs / is produced by the computerFor example, C:\> the current directory or pathA ParameterRefers to additional / qualifying information required for a commandFor example, wordpro.exe the name of the program to be executedAccess RightsEach user / group is allocated an access levelControls the access they have to specific data filesExample: Read OnlyAccess rights to a data file are held in a tableEnforced by username / password systemWhen a user tries to access a data file, the computer uses the tableChecks that they have appropriate level of accessIf they do not, access is deniedAuthorised UsersAccess rights to data filesWill be recorded in an access tableWhen a user attempts to modify dataThe user’s access rights will be checked in the access tableTo ensure they have EDIT / MODIFY / DELETE accessOnly if the user has appropriate rights will the modification be permittedDVD-RSufficient capacity to store a typical business applicationE.g. 4.38gbData can only be written to it once so its contents cannot be accidentally erased / alteredIt is light in weight so it incurs minimal postage costsAcceptable Use PolicyAcceptable Use PolicyHow user accounts should be usedSelecting secure passwordsRegular changing of passwordsKeeping passwords secureNot using another use’s passwordLogging off at the end of a sessionHow users should access dataWhat access is permitted and how that data can be usedWhat access is restrictedWhat a user should do if he / she accidentally accesses data which he / she is not permitted to accessHow users can access the Internet / emailWhat access is permitted / what types of websites may be visited / what email use is permittedWhat access is prohibited / what types of websites are prohibited / what email use is prohibitedTime restrictions on the use of the InternetHow the policy will be enforcedThe disciplinary processPenalties / sanctionsAppeal proceduresRationale for the policyDefines the employer’s rights / the employee’s responsibilities regarding the use of ICTIncluding proper use of e-mail and the Internet / how e-mail and the Internet should be used for business and personal useAnd how the use of ICT such as e-mail and the Internet will be monitored and policedIt will describe security proceduresSuch as secure logging on and offIt will prohibit actions which will compromise data securityE.g. the use of storage devices not checked for virusesIt will identify management and employee’s responsibilities relating to legislationsIt will define the disciplinary process / appeals processPenalties for non-complianceBackupBackup and RecoveryData should be backed up when processes are run / weekly / monthlyData should be backed up after installationBackup data should be copied to a portable mediumSuch as a CD / DVD / external hard driveStored away from the computer systemIncremental backupBacking up only the data that has been changed / modifiedQuicker than a full backupPotential to miss files, leading to incomplete backupFull backupBacking up all of the dataTakes timeEnsures all files are backed upBackup and Recovery suitable for Batch ProcessingBackupA complete backup would be suitableAll data files are backed upAn incremental backup is suitableOnly data has changed is backed upMaster data should be copiedJust before the batch processing takes placeOnto a portable mediumStored away from the computer systemTranscriptions in batch should also be copiedRecoveryThe master data should be restored from the backup copyThe batch of transactions should be processed againSuitable Backup and Recovery Strategy for Real Time ProcessingA RAID is often usedAn extract copyCalled a mirror imageOf all data / transactions is keptAll transactions are recorded on both systems simultaneouslyThe copy is stored at a remote / secure / separate locationIf the live system failThere is instant switch overTo the back upDisaster Recovery PlanTo ensure the organisation can continue operatingAfter a disaster / disruptionSuch as flooding / earthquakesTo ensure critical data has been identifiedAn alternative location may be establishedWhere the computer system can operating until the threat / damage is overTo ensure that key personnel have been identifiedWill continue to have access to the organisations computer systemsICT in BusinessHow the introduction of ICT has affected employees in businessesSome workers have been made redundant Robots can work more efficiently than humansThe work of many employees has been made saferRobots can operate in hazardous conditions e.g. paint spraying boothsThe work for many employees has been made less physicalRobots can be used to maneuver heavy componentsSome workers may be de-skilled / re-deployedICT systems can do their jobs more effectively How ICT can be used to help train employeesAn-line training course / Interactive DVDCan incorporate multimedia elementsWhich the users could use at their own paceVideoconferenceCan be used simultaneously to train a number of usersAt a number of geographically dispersed locationsAllows interaction between trainer and traineeOn-line course / tutorialEmployees log on and complete the course individuallyOn-Line TrainingCourse is delivered over the Internet / an intranetInteractive courseEach participants logs onAt a time convenient to themSets their own paceCan repeat / review previous sections / jump ahead of sectionsThe course content is presented using multimedia / video / audio / graphicsContext sensitive help may be providedParticipants may communicate with the instructor via email / forum / user groupsInformation may be disseminated to participants via bulletin boardsUser navigates through the course using simple controlsE.g. Next / Back buttonsInteractive indexDifferent navigation paths may be provided for different categories of usersThe progress of the trainees can be monitored electronicallyBenefits of Offshoring Call Centers etcReduced wage costsStandard of living in places like India is much lower than somewhere like the USAEffective use of international time zonesHelp desk can be manned at night in the USA by employees in India for example working during their dayThe business can focus on its core businessUse the services of a specialised provider of help desk facilities Benefits of using ICT to utilise TeleworkingLess / no time spent travelling to workThis time can be used more productivelyThis leads to reduced petrol costs / bus fares / train faresLocation is irrelevant Employees can access the companies ICT systems using the Internet / an intranetA better work-life balance / more flexible working hoursParents can combine working with childcarePeople with health problem (e.g. physical immobility) do not need to leave their homesBenefits of using the Internet to sell goodsIncreased potential marketThe Internet is a global networkSearch engines can direct Internet users to their websiteIncreased hours of businessThe Internet is active 24/7Better communication with customerse.g. mail-shots, email, reviewsThe company can sell e-books for exampleDownload to e-readerWhy a real shop may be preferredSome customers prefer to browse through actual itemsSample them before purchasingCustomers can speak directly to employeesAsk for advice / suggestionsThere is a perceived increased risk of identity fraud on the InternetAdvertising ICT Products: WebsiteWebsite can contain multimedia components E.g. animations / soundsWhereas a magazine for examples is restricted to text / graphics / staticWebsite could include demoPotential audience is worldwide / not restricted to a magazines readership for exampleAny internet user could be directed to the site via a search engineWebsite is available 24/7Website could include email linkCompany could aim to build up a database of potential usersContact them with promotionsHow ICT has affected shopping / bankingOnline / cashless shoppingCustomers can purchase goods (on the Internet / in stores) using credit / debit cardsIncreased risk of fraud / wider choice / no need to carry cash 24/7Online bankingCustomers can check balances / transfer funds / set up DDs and SOsIncreased risk of fraud / identity theft / 24/7Methods of obtaining softwareThe software could be purchased ready madeOff the ShelfFrom a computer store / specialist software shopThe software could be developed “in-house”By specialists within the businessThe software could be “out-sourced”To specialist software developersAdvantages of Off-the-Shelf software over a custom built / bespoke packageIt is immediately available for use?The cost will be shared among many users?It should be fully tested/should contain few errors?There should be support available from other users, e.g. via user groups?Training materials should be already availableImpact of ICT on employees working from home / TeleworkingAdvances in telecommunicationsSuch as broadbandEnable employees to access their organisation’s databaseAnd software / applicationsUsing the InternetUsually via an intranetIrrespective of locationSs they can work as effectively from home / do the same work at homeEmployees can communicate with managers / colleaguesUsing electronic bulletin boards / emailsOr using webcams / videoconferencingTeleworking: DrawbacksLess management control of the employees Most contact will be indirectEmployees cannot be observed directlyThere may be a lack of teamworkThe company must provide appropriate ICT resourcesSuch as a broadband connection / intranetAccess to databases / software via InternetProcessingBenefits of using Real Time ProcessingNo risk of recordings “clashing”As record locking can be used to prevent the same record being updates by two users at the same timeThere is instant / immediate feedbackInforming the user that the process has been carried out e.g. a reservationNormalisationNormalization1NFRemove repeating groups2NFRemove fields not dependent on the whole primary key / Remove non-key dependencies 3NFRemove fields (other than candidate keys) that depend on other non-key fieldsMobile Phone TechnologyMobile Phone TechnologySIM CardsA mobile phone contains a Subscriber Identity Module A smart card that gives the user access to a range of subscriber servicesThe SIM card identified the subscriber to the network systemThe NetworkThe country is divided into overlapping cellsEach uses a different set of radio frequenciesAt the center of each cell is a base stationConnected to an antenna (mobile phone mast) which communicates with all of the mobile phones in the cellA group of base stations is connected to a mobile telephone switching centerWhich will be connected to a second level MTSO, and so onThese switching offices are connected to the Public Telephone SystemGeneral Packet Radio Service (GPRS) / 3G protocols support mobile data streaming and transferMobilityEach mobile phone is controlled by the base station for the cell it is currently inWhen the phone is about to leave the cel, the base station detects that the received signal strength is fadingIt asks the surrounding base stations to report the power levels they are receiving from the phoneControl is transferred to the cell whose base station is receiving the strongest signalA message is sent to the phone informing it that it will be under the control of a different base stationIt must switch to a new frequencyMobile Phone NetworkRadio frequency waves are used for communication information?When a mobile phone connects to a network it communicates with the nearest base station?The area covered by a base station is known as a cell?Each cell is usually split into three sectorsWhich overlap with the sectors of neighbouring cellsTo create an uninterrupted network?When people travel, the signal is passed from one base station to the next?And usually never has to travel further than the nearest base station?Cells are connected to cellular telephone exchange switchesWhich are connected to the public telephone network /other exchange switchesICT LawsICT LawsCopyright, Designs and Patents ActApplies the concept of intellectual property/ownership to software A license is required for copyrighted software?It is illegal to copy unlicensed software?It is illegal to distribute unlicensed softwareComputer Misuse ActIt is illegal to access computer material without permissionOr to access materials with intent to commit or facilitate a crime Or to modify materials without permissionMain Implications of Data Protection legislationOrganisationData users must registerMust comply with the DPA’s 8 principlesMust appoint a DP officerMust identify what data will be storedAnd the purpose for which it is being processed / the processing performedRelevant staff must be informed and trainedProcedures must be set in place to ensure complianceExample:The data user must implement good information practice specifying how data is kept secure / up to dateMembers of the publicThese are the data subjectsConfidence that data held about them is accurate / up to dateData subject have the right to see the data held about themAnd have any errors correctedThere are cost implications – a fee can be chargedCompensation may be available if their rights are contravenedSoftware PiracyThe illegal distribution and / or reproduction of software which can results in serious loss of revenueNumber of steps to make piracy more difficultSoftware could be distributed in encrypted formEach copy requires a unique key or code before it can be installedWhen this key is used to install the software it locks the software so it cannot be installed on other computersHardware key or dongle can be used to the same effectSpecial software can be used to prevent a disk from being copiedCompanies could consider Digital Rights Management issuesAutomatic key generation software is widely availableAs is disk cloning softwareEasily rendering many methods useless allowing piracyLegislationPiracy is punishable by law, whether deliberate or notSoftware will be covered by the Copyright, Designs and Patents ActApplies the concept of intellectual property / ownership to softwareWithin the UK The Act states that “an article is an infringing copy if its making constituted an infringement of the copyright in the work in question”A licence will be required for the computer gameIt will be illegal for anyone to copy the game without the companies permission / if not covered by a site / multiple user licenceIt will be illegal for anyone to distribute the software without the companies permission / an appropriate licenceThe penalties for breaking this Act include a term in prison and an unlimited fineLegislation is difficult to enforce Will be on the company to detect and prosecute offendersSupport is available from the Federation Against Copyright Theft (FACT)Acts against counterfeiting, copyright and trademark infringements Management Information SystemManagement Information System (MIS)A MIS transforms large amounts of (raw) data?From a data processing system/using transaction data?Into useful information?Which is necessary for a business to be managed effectively/ achieve its goals?Which is used by different levels of management?It utilizes data from many sources?Including internal and external sources?Appropriate queries and reports are generated?For routine and non-routine purposesDecision Support SystemDecision Support SystemIt assists managers in solving complex business problems By applying different business models to dataThe problems may be ad hoc/complex?Or unstructured/semi-structured problemsSuch as ‘what if’/using goal seeking/risk analysis?Assists organisations with strategic/tactical/operational decision making?It may incorporate an expert systemDecision Support SystemAssists managers in solving complex business problemsApplies various business models to dataThe problems may be ad hoc / complexOr unstructured / semi-structured problems‘What-if’ analysis can be performedGoal seekingRisk analysis may be usedAssists organisations with strategic / tactical / operational decision makingDatabasesDatabase AdministratorDefining/maintaining/modifyingThe database structureTables/attributes/keys/relationships/schema/data dictionary?Controlling access to the databaseE.g. assigning access rights/allocating user names & passwords?/creating ‘user views’?Designing/modifying standard queries/reports/macros?Identifying new user query and report requirements/liaising with users Keeping users informed of changes relevant to the user e.g. additional reports Managing on-going user training?Managing/monitoring back ups?Ensuring compliance with legislation e.g. the DPADatabasesCentralised DatabaseSingle copy of the database held at a central locationInformation such as prices will be updated directlyAny data amendments (e.g. stock levels) Will be generated at branch levelCommunicated to the centralised databaseAnd the database updatedData ConsistencyEnsured as there is only a single copy of the databaseUser access to dataAll users access the single copy of the data so access times are greater due to distances involved The volumes of access at the central location will be high and there may be a deterioration in performanceIf the central location fails, the entire database failsData SecuritySimpler to enforce centralised security measures on a single copy of the databaseThe increased volume of data traffic may be more vulnerable to interceptionDistributed DatabaseRelevant copies of part of the database will be held at each locationAs that is where it will be most frequently accessedData amendments will be implemented in the database at the appropriate locationThe scattered versions of the database must be synchronisedEnsuring they all have consistent dataEach location gets a daily copy of dataData ConsistencyThere may be multiple values of the same data in different locationsA field may be updated at one location only A field may be updated to different values at two different locationsThe data has to be reconciled at regular intervalsUser access to dataUsers have faster access to their local data as the data is stored locallyVolumes of access at each location will be reducedIf one location fails, only that part of the database is affectedData SecurityIt is more complicated to enforce uniform security measures across a number of locationsIt is simpler to enforce security measures at a single locationThe decreased volume of data traffic will be less vulnerable to interceptionExpert SystemExpert SystemA user interfaceThe user keys in facts to the expert system about the problemReceives a solution and reason / explanationA knowledge / rule baseContains information / heuristics, rules about the problem domain / expert knowledgeRepresents the knowledge of human expertsAn inference engine / mechanismApplies the rules using the user’s inputDraws conclusionCan apply fuzzy logicExpert SystemRule BaseContains knowledge / heuristics / connections / factsAbout the problem domainDerived from human expertsInference engineApplies the rulesUsing the user’s inputDraws conclusionsFuzzy logic may be usedExpert system can apply the knowledge of a number of very experienced users from a certain industryCan produce very accurate diagnosesUp to date diagnosesConsistentlyProvide reasoning / probabilitiesCannot replace human intuitionE.g. where a user may sense or guess a problemHumans can learn from their mistakesRisk of over reliance on technologyUsers may become deskilled ................
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