Page ‹#›Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 1A Case Study:The International FilmVideo StoreInformation Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 2The International Film Video StoreThe International Film Video Store This store was founded by a couple of friends wholike international cinema. The store has beenlocated near one of Toronto’s repertoire theatresand has been in operation for four years. Unfortunately, the store is barely scrapping a livingbecause of insufficient rentals, especially during thesummer when the neighbouring repertoire theatre isclosed. Problem: “Increase video rentals”Page ‹#›Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 3Where Do We Start? How do video rentals happen? Could they happendifferently? (…tactical analysis)Rent VideoDeliver/ReturnVideoPayBrowse CollectionSelectVideoPhysicallyElectronicallyPhysicallyElectronicallyPhysicallyElectronicallyCustomerCourierElectronicallyInformation Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 4StrategicAnalysisIncrease Video RentalsOpen Many Stores(Phys)Bring StoreCloser to MoreWeb-BasedRentals(Electr-Courier)EnrichCollectionBroadenCollectionWeb-BasedRentals(Electr)+++DevelopmentCostCostOperationalCostCompetitiveAdvantageMarketNiche+----+CompetitivePrice-Low Price++Profitable-Page ‹#›Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 5What Are the LeadingAlternatives? Electronic solution, no physical store -- higherdevelopment costs, lower operational costs; Electronic solution, courier service -- OK for userswho rent in bulk; Broaden collection to include more foreignlanguages -- need selectors, suppliers; Deliver videos to N (e.g., 10) locations aroundToronto; customers can pick up/drop off videosthereInformation Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 6Choose an Alternative Suppose we decide to recommend the lastalternative. This means that a customer chooses videos from aweb-based system, these videos are delivered tothe location closest to her, she returns the videos tothat location, and they are sent back to the videostore warehouse.Page ‹#›Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 7RSD: Describe Functional andNon-Functional Requirements Describe each functional requirements in English. Describe each non-functional requirement in English. Describe data to be managed by the system. Organize and number both functional and non-functional requirements so that they can be referred tolater on. Trace each functional requirement. Indicate the strength of each requirement e.g., verystrong --> must have, weak --> could skip if things fallbehind.Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 8RSD: NFRs Security and privacy. Reliability Performance -- throughput, response time … Relate each of these to the UML diagrams youinclude in appendicesPage ‹#›Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 9RSD: System Interfaces, Data, I/O Specify in the RSD:Interface with courier DB: data exchanged;Interface with credit card co DB: data exchanged;Data to be managed by the system (customers,rental items, rentals,…)Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 10Modeling in UML:Business Processes We start with the business processes to be supportedby the system; use state diagrams or activity diagramsto model them:Rent-Deliver-Pickup-Return-ReturnToStore-Remind;Rent in detail (includes payment authorization withcredit card company);Deliver once a day in detail (includes communicationwith courier database)Return to repository in detail (includescommunication with courier database)Remind customer about overdue videos.Page ‹#›Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 11Use CasesUse cases correspond roughly to the functionalrequirements of the system. Customer use cases: browse, select, choose, pay; Employee use cases:list of videos for each location (each day);list of videos from each location each day;remind customer electronically;charge delinquent customer. Manager use cases:Report at the end of each week;Report on dormant customers (once every6months); Systems person use cases: start system; get reporton failure,…Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 12Documenting Use Cases Describe each use case in English, including thesteps required, I/O,… Model each use case in terms of one or moresequence diagrams (normal case, exceptionalcases.)Page ‹#›Information Systems Analysis and Design csc3402004 John MylopoulosCase Study -- 13What Kinds of Objects Are WeWhat Kinds of Objects Are WeTalking About?Talking About? RentalItem VideoCp DVDCp Film RentalCustomerUse CL to model constraints, pre/post-conditions to specifyBusiness rules, pre/post-conditions for
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