Why Is Testing Stage of Sdlc so Important?

Why is the interrogation stage of establishments development so substantial? zero(prenominal)ember 2012 Introduction establishments Development Life round of drinks Types of SDLC Stages of SDLC falls method interrogatory Programme examen Acceptance interrogation Limitations of examination mooring training 1 University of Salford Case Study 2 Knight Capital Group Summary cobblers last References Systems Development Lifecycle Systems Development Life rhythm method of birth control (SDLC) is the process of developing schooling dodgings through heterogeneous stages from identifying initial requirements through analysis, design, scrutiny, mplementation and maintenance. Many different models moreover each generally consists of a series of defined steps or stages. Laudon & Laudon (2006) Types of SDLC Waterfall Fountain Spiral Rapid prototyping Incremental Bocij et al (2006) Waterfall One of the oldest, best known Linear sequential set of phases crit ical review at end of each phase in the beginning moving on to the next Logical chain of events, e. g. programming cannot begin until stipulation realized Many different versions Many critics does not work? Laplante & Neill (2004) Dennis et al (2008) Stages of SDLCVary agree to the methodology used just usually some variation of the waterfall method which has Galin (2004) served as a framework for others. Systems analysis identify problems & micturate requirements Systems Design create design specifications Programming translate design specification into code Testing Conversion plan conversion, train users Production & support operate, evaluate and modify the system Laudon & Laudon (2006) Testing Why test? System should be tried to ensure that it meets the requirements laid out at the sorb of the process. Develop a test plan Involve users as rise as developers Simulate info and test system processes e. g. entering a new record, inserting incorrect data Laud on & Laudon (2006) Test Plan Test enumerate Purpose of Test Test Data Expected Result developed Result 1 Test the validation bump on the run across of Birth field to ensure that valid get words of birth can be entered. 15/02/1988 accredited Accepted 2 Test the validation tower on the Date of Birth field to ensure that a date in the future cannot be entered. 14/10/2013 Rejected Accepted Adapted from Laudon & Laudon (2006) Testing 2 basic phases of test programme examination ensures that the programmes work as expected in controlled environment acceptance testing ensures users are able to use the system and that it operates as expected when in use. Laudon & Laudon (2006) Programme Testing 3 phases unit testing individual modules of the system are tested for any potential errors in the code. integration testing to check the modules work together as expected complete system testing see how all the components will work under various conditions Bocij et al (2006) Acceptan ce Testing User Acceptance Testing (UAT) by actual end users of the ystem to take in how well it meets their expectations and requirements. alpha testing utilise simulated data beta testing using actual data final stage before implementation Bocij et al (2006) Acceptance Testing Security testing whether security policies have been implemented as intend Recovery testing how the system reacts when it has been forced to fail Performance testing in different environments Stress testing attempts to break the system by not following guidelines. Looks at how the system performs under heavy demand. Bocij et al (2006) Limitations of Testing Impossible to guarantee that once a system is tested it will work exactly as expected Too some factors to carry out exhaustive testing It is often given shy(predicate) importance and other stages overrun at the expense of testing Cannot rule out unforeseen problems further down the line BUT Gives a good idea, identifies major errors Mo rris (2005), Bocij et al (2006) Case Study 1 Careers good New system to manage Careers Service engagements, workshops and events Alpha testing revealed few errors which were resolved Beta testing revealed significant issues re student status, ducation details, appointment booking abilities Issues were resolved and pilot system launched Phased implementation. Testing continues Case Study 2 Knight Capital Group commerce US equities electronically (high frequency trading) Dormant software from a legacy system inadvertently reactivated Multiplied stock trades by 1000 45 minute train in shutting down the system Proper testing and purloin market simulations Estimated $440M loss Detterman (2012), Ruhle, Harper and Mehta (2012) Summary Defined SDLC Types & Stages of SDLC Types of Testing Limitations of Testing Case studies demonstrate importance of thorough testing Conclusion Testing reveals any errors and incompatibilities Essential to ensure they can be corrected before implementation Testing is a continual process. There needs to be a cut off point before implementation but it can (and should) continue Testing is critical because it is the only way to determine whether the system operates to requirements and actually works Laudon & Laudon (2006), Cervone (2007) References Cervone, H. F. (2007),The system development life cycle and digital library development, O CLC Systems & Services, Vol. 3 Iss 4 pp. 348352 online. forthcoming from Accessed 12 November 2012 Dennis, A. , Wixom, B. H. & Roth, R. M. (2008) Systems Analysis and Design, 4th Edn, Oxford Wiley Detterman, E. (2012) Software Development Life Cycle (SDLC) Case Study Result = $440m Loss. Solid Logic Technology. 12 solemn 2012 online. Available from Accessed 11 November 2012 Galin, D. (2004) Software Quality Assurance from theory to implementation. Harlow Pearson teaching method Laplante, P. A. & Neill, C. J. (2004), The Demise of the Waterfall Model Is Imminent and Other Urban Myths, ACM Queue, Vol 1, No. 10 onliine.Available from Accessed 12 November 2012 Laudon, K. C. and Laudon, J. P. (2006) Essentials of Management Information Systems Organization and Technology in the Networked Enterprise, ninth ed. , New Jersey Prentice-Hall Morris, S. , (2005) Software Development Cycle, Tessella halt Services plc, available at http//www. tessella. com/wp-content/uploads/2008/05/softwaredevelopmentcycle. p df accessed 12 November 2012 Ruhle, S. Harper, C. & Mehta, N. (2012) Knight Trading Loss Said to Be Linked to Dormant Software. Bloomberg. 14 rattling(a) 2012. online Available from Accessed 01-11-2012