Comparison between five process models of software engineering Essay

IJCSI internationalist daybook of figurer skill jazzs, Vol. 7, Issue 5, folk 2010 ISSN (Online) 1694-0814www.IJCSI.orgA Comparison Between Five puts Of packet EngineeringNabil Mohammed Ali Munassar1 and A. Govardhan21Ph.D Student of figurer recognition & EngineeringJawahrlal Nehru technical UniversityKuktap every in ally, Hyderabad- vitamin D 085, Andhra Pradesh, India2Professor of estimator scholarship & EngineeringPrincipal JNTUH of Engineering College, Jagityal, Karimnagar (Dt), A.P., India mulctThis enquiry deals with a vital and master(prenominal) issue in reck adeptr world. It is re recent with the bundle management recognise fores that examine the celestial sphere of softw be dodging program product body growth through the festering manikins, which argon k equal a shotn as parcel constitution system package program education t cardinal roulette wheel. It proves five of the phylogeny mannequins namely, falls, Iteration, V-shaped, curl and Extreme programming. These stupefys have advantages and disadvantages as hearty. at that placefore, the main objective of this research is to represent different poseurs of parcel ontogenesis and quarter a compare between them to fork over the features and defects of severally prototype.Keywords packet package program Management surgical processes, package organic evolution, Development Models, software package Development behaviorturn, Comparison between five rides of parcel Engineering.increased recently which results in the breast knead ofenumerating such companies. During the previous fourdecades, software has been developed from a tool utilize foranalyzing information or solving a task to a product initself. However, the earlier programming stages havecreated a number of problems turning software anobstacle to software development break officularly thoserelying on computers. software package consists of documents andprograms that contain a accumula tion that has been essayed to be a part of software technologyprocedures. Moreover, the aim of software engineering isto create a suited work that construct programs of high part.1. representation ready reckoner scientific disciplineNo superstar chiffonier deny the importance of computer in our life,especially during the present time. In fact, computer hasbecome indispensible in forthwiths life as it is apply in m anyfields of life such as industry, medicine, commerce,education and in time agriculture. It has become animportant element in the industry and technology ofadvanced as well as developing countries. straightaway a days,organizations become more(prenominal) qualified on computer intheir whole kit as a result of computer technology. Computeris considered a time- saving doohickey and its progress helpsin executing complex, long, iterate handlees in a very poor time with a high speed. In addition to usingcomputer for work, mint habituate it for fun andente rtainment. Noticeably, the number of companies that wee software programs for the purpose of facilitating kit and boodle of offices, administrations, banks, etc, hasTheoriesComputer subprogramClientProblemsThe software system engineeringTools and techniques to reply problemsFig. 1 Explanation of software engineering conception.IJCSI International Journal of Computer science Issues, Vol. 7, Issue 5, September 2010 ISSN (Online) 1694-0814www.IJCSI.org952. computer software Process Modelsconcern.A software suffice gravel is an abstract representation of a extremity. It presents a description of a address from both(prenominal)particular perspective asThe sublimate waterfall lifecycle consists of several(prenominal) nonoverlapping stages, as shown in the follo get alongg figure. The bewilder begins with establishing system dealments andsoftware requirements and continues with architectural human body, detailed inclination, coding, streamleting, and charge.The waterfall gravel serves as a baseline for umpteen a nonher(prenominal)lifecycle cases.1.2.3.4.Specification. cast.Validation.Evolution.General computer software Process Models are1. waterfall warning Separate and distinct forms ofstipulation and development.2. specimen model.3. Rapid application development model (RAD).4. EvolutionarydevelopmentSpecification,development and governing body are interleaved.5. Incremental model.6. repetitive model.7. volute model.8. Component-based software engineering The systemis assembled from actual components.System Requirementssoftware product RequirementsArchitectural targetDetailed DesignCoding on that point are many variants of these models e.g. formaldevelopment where a waterfall-like work at is apply, preciselythe particularisedation is formal that is refined through severalstages to an implementable flesh1. scrutiny aidFig. 2 waterfall Model4.3. Five ModelsA schedule movement model is an abstractrepresentation to tie the pro cess from a particularperspective. on that point are numbers of general models forsoftware processes, like waterfall model, Evolutionarydevelopment, dress systems development and Reusebased development, etc. This research pass on view the following five models 1. waterfall model.2. Iteration model.3. V-shaped model.4. roll model.5. Extreme model.These models are chosen because their featurescorrespond to most software development programs.RequirementsDefinitionSystem andsoftware product DesignImplementationand whole interrogationIntegration andSystem auditioning3.1 The Waterfall ModelThe waterfall model is the unmingled model of softwareengineering. This model is one of the oldest models and iswidely used in political sympathies construes and in many majorcompanies. As this model empha sizes be after in beforehand(predicate)stages, it vouchs t end upency flaws in the first place they develop. Inaddition, its intensive document and readiness make itwork well for ma kes in which quality secure is a majorOperation andMaintenanceFig. 3 Waterfall model2.The following refer details the steps for using the waterfallIJCSI International Journal of Computer lore Issues, Vol. 7, Issue 5, September 2010 ISSN (Online) 1694-0814www.IJCSI.orgmodel1 System requirements Establishes the componentsfor building the system, including the hardwarerequirements, software tools, and separate necessarycomponents. Examples include decisions onhardware, such as plug-in get ons (number ofchannels, acquisition speed, and so on), and decisionson external gos of software, such as databases orlibraries.23Software requirements Establishes the expectationsfor software functionality and identifies which systemrequirements the software affects. Requirements abstract includes determining interaction needed withother applications and databases, performancerequirements, user interface requirements, and so on.Architectural innovation even ups the software textile of a system to meet the ad hocrequirements. This design defines the majorcomponents and the interaction of those components,but it does non define the structure of from all(prenominal) onecomponent. The external interfaces and tools used inthe take in can be controld by the designer.4Detailed design Examines the software componentsdefined in the architectural design stage and producesa specification for how from each one(prenominal) component isimplemented.5CodingImplementsspecification.67thedetailedstarting coding. There is no overlap between stages. Inreal-world development, however, one can discover issuesduring the design or coding stages that point egress errors orgaps in the requirements.The waterfall order does not prohibit returning to an front configuration, for example, returning from the design physical bodyto the requirements phase. However, this involves high-ticket(prenominal)rework. apiece roll in the hayd phase requires formal review andextensive reinforcement development. Thus, oversightsmake in the requirements phase are expensive to correctlater.Because the actual development comes late in the process,one does not see results for a long time. This delay can bedisconcerting to management and clients. legion(predicate) peoplealso think that the center of documentation is excessiveand inflexible.Although the waterfall model hasinstructive because it emphasizesproject development. Even if onemodel, he must consider each ofrelationship to his own project 4.1.2.3.design analyseing dates whether the software meets the specify requirements and finds any errors present inthe code.Maintenance Addresses problems and sweetenerrequests after the software releases.In roughly organizations, a falsify control board maintainsthe quality of the product by reviewing each change madein the maintenance stage. Consider applying the fullwaterfall development cycle model when correctingproblems or implementing these enhancement requests.In each stage, documents that explain the objectives and pull out the requirements for that phase are created. At the completion of each stage, a review to determine whether theproject can proceed to the bordering stage is held. Yourprototyping can also be incorporated into any stage fromthe architectural design and after.Many people opine that this model cannot be applied toall situations. For example, with the arrant(a) waterfall model,the requirements must be state in brieferhand beginning thedesign, and the complete design must be stated before964.5.6.1.2.4.5.6.7.its weaknesses, it isimportant stages ofdoes not apply thisthese stages and itsAdvantages Easy to understand and implement. astray used and known (in theory).Reinforces dear(p) habitsdefine-before- design,design-before-code.Identifies deliverables and milestones.Document driven, URD, SRD, etc. Publisheddocumentation standards, e.g. PSS-05.Works well on ripe(p) products and weak aggroups.Disadvantages Idealized, doesnt matc h man well.Doesnt reflect iterative genius of exploratorydevelopment.3. Unrealistic to expect dead-on(prenominal) requirements soearly in project.Software is delivered late in project, delays discoveryof grievous errors. uncorrectable to integrate stake management. unvoiced and expensive to make changes todocuments, swimming upriver.Significant administrative overhead, costly for teensyteams and projects 6.Pure WaterfallThis is the classical system development model. It consistsof discontinuous phases1.2.3.Concept.Requirements.Architectural design.IJCSI International Journal of Computer acquisition Issues, Vol. 7, Issue 5,September 2010 ISSN (Online) 1694-0814www.IJCSI.org4.5.6.Detailed design.Coding and development. proveing and slaying.Table 1 Strengths & Weaknesses of Pure WaterfallStrengthsMinimizes planningoverhead since it canbe done up front.Structure minimizes in straitened circumstances(p) effort, so itworks well fortechnically weak orinexperienced staff. jeopardize drop-off scrolls can be added to the return of thewaterfall to reduce trys prior to the waterfall phases. The waterfall can be however modify using options such asprototyping, JADs or CRC sessions or other orders ofrequirements meeting done in overlapping phases 5.Weaknesses3.2 iterative aspect DevelopmentInflexibleOnly the utmost phaseproduces a nondocumentationdeliverable.Backing up toaddress mistakes is tall(prenominal).The problems with the Waterfall Model created a demandfor a new method of developing systems which could permit faster results, require less up-front information,and offer greater flexibility. With iterative Development,the project is divided into low parts. This allows thedevelopment team to demonstrate results earlier on in theprocess and obtain semiprecious feedback from system users.Often, each iteration is in reality a mini-Waterfall processwith the feedback from one phase providing vitalinformation for the design of the attached phase. In a va riation of this model, the software products, which are producedat the end of each step (or series of steps), can go intoproduction immediately as additive releases. Pure Waterfall SummaryThe plain waterfall model performs well for products with clear understood requirements or when working(a) withwell understood technical tools, architectures andinfrastructures. Its weaknesses keep goingly make itinadvisable when rapid development is needed. In thosecases, modified models may be more pithive.97 special WaterfallThe modified waterfall uses the same phases as the slenderwaterfall, but is not based on a discontinuous basis. Thisenables the phases to overlap when needed. The purewaterfall can also adjourn into subprojects at an appropriatephase (such as after the architectural design or detaileddesign).Table 2 Strengths & Weaknesses of modify WaterfallStrengthsMore flexible than thepure waterfall model.If at that place is personnelpersistence between thephases, documentationc an be substantiallyreduced.Implementation of easyareas does not need towait for the hard ones.WeaknessesModified Waterfall SummaryMilestones are moreambiguous than thepure waterfall.Activities performedin duplicate are subjectto miscommunicationand mistakenassumptions. out of the blue(predicate)interdependencies cancreate problems.Fig. 4 Iterative Development.3.3 V-Shaped ModelJust like the waterfall model, the V-Shaped life cycle is a sequential path of execution of processes. each(prenominal) phasemust be completed before the next phase begins. assayingis accent in this model more than the waterfallmodel. The seeing procedures are developed early in thelife cycle before any coding is done, during each of thephases forego capital punishment. Requirements begin thelife cycle model just like the waterfall model. in the first placeIJCSI International Journal of Computer recognition Issues, Vol. 7, Issue 5, September 2010 ISSN (Online) 1694-0814www.IJCSI.orgdevelopment is star ted, a system outpouring plan is created. The block out plan focuses on meeting the functionality specified inrequirements gathering.98RequirementsThe high-level design phase focuses on systemarchitecture and design. An integration test plan is created in this phase in order to test the pieces of the softwaresystems ability to work together. However, the low-altitudedesign phase lies where the actual software componentsare designed, and unit tests are created in this phase aswell.System examinationPlanningHigh LevelDesignLow LevelDesignThe implementation phase is, again, where all codingtakes place. erstwhile coding is complete, the path ofexecution continues up the right side of the V where thetest plans developed earlier are now put to use.Simple and easy to use.Each phase has specific deliverables.Higher incur of success over the waterfall modeldue to the early development of test plans during thelife cycle.Works well for small projects where requirements areeasily understoo d.Unit TestPlanningIntegrationTestingUnitTestingImplementationAdvantages1.2.3.IntegrationTestPlanningSystemTesting4.Fig. 6 V-Shaped Life cycle Model7.3.4 coiling ModelThe corkscrew model is similar to the additive model, withmore emphases placed on jeopardize abridgment. The spiral modelhas four phases Planning, find Analysis, Engineering andEvaluation. A software project repeatedly passes throughthese phases in iterations (called Spirals in thismodel). The baseline spiral, starting in the planningphase, requirements are gathered and risk isassessed. Each subsequent spiral builds on the baselinespiral. Requirements are gathered during the planningphase. In the risk analysis phase, a process is undertakento identify risk and alternate solutions. A prototype isproduced at the end of the risk analysis phase. Software isproduced in the engineering phase, along with testing atthe end of the phase. The evaluation phase allows the guest to judge the output of the project to datebe fore the project continues to the next spiral.In the spiral model, the angular component representsprogress, and the radius of the spiral represents cost.Fig. 5 V-Model 3Disadvantages1.2.Very rigid like the waterfall model.Little flexibility and adjusting mountain chain is ambitious andexpensive.Software is developed during the implementation phase,so no early prototypes of the software are produced.This Model does not provide a clear path for problemsfound during testing phases 7.3.4.1.2.3.AdvantagesHigh amount of risk analysis.Good for large and mission-critical projects.Software is produced early in the software life cycle.1.2.3.Disadvantages trick be a costly model to use.Risk analysis requires exceedingly specific expertise.Projects success is highly dependent on the riskanalysis phase.Doesnt work well for little projects 7.4.IJCSI International Journal of Computer Science Issues, Vol. 7, Issue 5, September 2010 ISSN (Online) 1694-0814www.IJCSI.org1.Spiral model sectorsObje ctive setting Specific objectives for the phase areidentified.2. Risk assessment and reduction Risks are assessed andactivities are put in place to reduce the key risks.3. Development and validation A development modelfor the system is chosen which can be any of thegeneral models.4. Planning The project is reviewed and the next phaseof the spiral is mean 1.99under which the system would produce win-lose or loselose outcomes for some stakeholders. 3. Identify and try Alternatives Solicitsuggestions from stakeholders, evaluate them with respectto stakeholders win conditions, synthesize and negotiatecandidate win-win alternatives, analyze, assess, fragmentizewin-lose or lose-lose risks, record commitments and areasto be leftfield flexible in the projects design record and lifecycle plans.4. Cycle through the Spiral expand the win conditionsevaluate and screen alternatives, resolve risks, accumulateappropriate commitments, and develop and inclinedownstream plans 8.3.5 Extreme Prog rammingAn ascend to development, based on the developmentand delivery of very small increments of functionality. Itrelies on immutable code improvement, user involvement inthe development team and pair sagacious programming . It canbe difficult to keep the interest of customers who are obscure in the process. Team members may be unsuitedto the intense involvement that characterizes briskmethods. Prioritizing changes can be difficult where thereare multiple stakeholders. Maintaining simplicity requires free work. Contracts may be a problem as with other glide slopeinges to iterative development.Fig. 7 Spiral Model of the Software Process1. WinWin Spiral ModelThe original spiral model Boehm 88 began each cycle ofthe spiral by performing the next level of enlargement ofthe prospective systems objectives, constraints andalternatives. A primary difficulty in applying the spiralmodel has been the lack of explicit process guidance indetermining these objectives, constraints, and alt ernatives. The Win-Win Spiral Model Boehm 94 uses the theoryW (win-win) approach Boehm 89b to converge on asystems next-level objectives, constraints, andalternatives. This Theory W approach involves identifyingthe systems stakeholders and their win conditions, andusing negotiation processes to determine a inverselysatisfactory set of objectives, constraints, and alternatives for the stakeholders. In particular, as illustrated in thefigure, the nine-step Theory W process translates into thefollowing spiral model extensions1. Determine Objectives Identify the system life-cyclestakeholders and their win conditions and establish initialsystem boundaries and external interfaces.2. Determine Constraints Determine the conditionsFig. 8 The XP Release Cycle Extreme Programming PracticesIncremental planning Requirements are recorded on grade Cards and the Stories to be included in a release are find out by the time available and their congener priority. The developers break these stories i nto developmentTasks.Small Releases The negligible useful set of functionalitythat provides business order is developed first. Releases of the system are frequent and incrementally addfunctionality to the first release.IJCSI International Journal of Computer Science Issues, Vol. 7, Issue 5, September 2010 ISSN (Online) 1694-0814www.IJCSI.orgSimple Design Enough design is carried out to meet thecurrent requirements and no more.Test first development An automated unit testframework is used to write tests for a new piece offunctionality before functionality itself is implemented.Refactoring All developers are anticipate to re-factor thecode continuously as soon as possible code improvementsare found. This keeps the code simple and maintainable.Pair Programming Developers work in pairs, checkingeach others work and providing support to do a good job.Collective monomania The pairs of developers work onall areas of the system, so that no islands of expertisedevelop and all the devel opers own all the code. Anyonecan change anything.Continuous Integration As soon as work on a task iscomplete, it is integrated into the whole system. afterwards anysuch integration, all the unit tests in the system must pass. sustainable pace Large amounts of over-time are notconsidered acceptable as the net effect is often to reducecode quality and medium term productivity.On-site node A representative of the end-user of thesystem (the node) should be available full time for theuse of the XP team. In an extreme programming process,the customer is a member of the development team and isresponsible for bringing system requirements to the teamfor implementation.1.2.3.4.5.XP and agile principlesIncremental development is back up through small,frequent system releases.Customer involvement means full-time customerengagement with the team.People not process through pair programming,collective self-control and a process that avoids longworking hours.Change supported through steady s ystem releases.Maintaining simplicity through unvarying refactoring ofcode 1.1.2.3.4.5.AdvantagesLightweight methods suit small-medium size projects.Produces good team cohesion.Emphasises final product.Iterative.Test based approach to requirements and qualityassurance.1.DisadvantagesDifficult to scale up to large projects wheredocumentation is essential.Needs experience and skill if not to degenerate intocode-and-fix.Programming pairs is costly.2.3.4.100Test case construction is a difficult and specializedskill 6.4. Conclusion and future tense WorkAfter completing this research , it is concluded that 1. There are many existing models for developingsystems for different sizes of projects andrequirements.2. These models were formal between 1970 and1999.3. Waterfall model and spiral model are used usuallyin developing systems.4. Each model has advantages and disadvantages for thedevelopment of systems , so each model tries toeliminate the disadvantages of the previous modelFinally, some topics can be suggested for future works1.2.3.Suggesting a model to simulate advantages that arefound in different models to software processmanagement.Making a comparison between the suggested modeland the previous software processes managementmodels.Applying the suggested model to many projects toensure of its suitability and documentation to explainits machinelike work.REFERENCES1 Ian Sommerville, Software Engineering, AddisonWesley, 7th edition, 2004.2 CTG. MFA 003, A Survey of System DevelopmentProcess Models, Models for Action Project Developing applicatory Approaches to Electronic Records Managementand Preservation, Center for engine room in GovernmentUniversity at capital of New York / Suny,1998 .3 Steve Easterbrook, Software Lifecycles, Universityof Toronto Department of Computer Science, 2001.4 bailiwick Instruments Corporation, Lifecycle Models,2006 , http//zone.ni.com.5 JJ Kuhl, Project Lifecycle Models How They Differand When to Use Them,2002 www.businessesolu tions.com.6 Karlm, Software Lifecycle Models, KTH,2006 .7 Rlewallen, Software Development Life CycleModels, 2005 ,http//codebeter.com.8 Barry Boehm, Spiral Development Experience,Principles, and Refinements, edited by Wilfred J.Hansen, 2000 .Nabil Mohammed Ali Munassar was born in Jeddah, SaudiArabia in 1978. He studied Computer Science at University of Science and Technology, Yemen from 1997 to 2001. In 2001 heIJCSI International Journal of Computer Science Issues, Vol. 7, Issue 5, September 2010 ISSN (Online) 1694-0814www.IJCSI.orgreceived the live degree. He studied Master of culture Technology at Arab Academic, Yemen, from 2004 to 2007. Nowrdhe Ph.D. Student 3 year of CSE at Jawaharlal NehruTechnological University (JNTU), Hyderabad, A. P., India. He is working as Associate Professor in Computer Science &Engineering College in University Of Science and Technology, Yemen. His area of interest include Software Engineering, System Analysis and Design, Databases and Object orient atedTechnologies.Dr.A.Govardhan received Ph.D. degree in Computer Scienceand Engineering from Jawaharlal Nehru Technological University in 2003, M.Tech. from Jawaharlal Nehru University in 1994 and B.E. from Osmania University in 1992. He is work as aPrincipal of Jawaharlal Nehru Technological University, Jagitial. He has published around 108 text file in various national andinternational Journals/conferences. His research of interest includes Databases, Data memory & Mining, InformationRetrieval, Computer Networks, Image Processing, SoftwareEngineering, Search Engines and Object Oriented Technologies. ci