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Chapter 3
McGraw-Hill/Irwin Copyright 2007 by The McGraw-Hill Companies, Inc. All rights reserved.
Information SystemsDevelopment
Objectives
Describe the motivation for a system development process interms of the Capability Maturity Model (CMM) for qualitymanagement.
Differentiate between the system life cycle and a systemdevelopment methodology.
Describe 10 basic principles of system development.
Define problems, opportunities, and directivesthe triggers fors stems develo ment ro ects.
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Describe the PIECES framework for categorizing problems,opportunities, and directives.
Describe the essential phases of system development. For eachphase, describe its purpose, inputs, and outputs.
Describe cross life cycle activities that overlap multiple system
development phases. Describe typical alternative routes through the basic phases of
system development. Describe how routes may be combined orcustomized for different projects.
Describe various automated tools for system development.
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Process of SystemDevelopmentSystem development process a set of activities,
methods, best practices, deliverables, and automated
tools that stakeholders (Chapter 1) use to develop and
continuously improve information systems andsoftware (Chapters 1 and 2).
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Many variations
Using a consistent process for system development:
Create efficiencies that allow management to shiftresources between projects
Produces consistent documentation that reduceslifetime costs to maintain the systems
Promotes quality
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Proses pengembangan sistem adalahserangkaian kegiatan, metode, bestpractices, keluaran dari suatu proses, dan
pemilik untuk mengembangkan danmerawat sistem informasi dan piranti
lunak
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CMM Process ManagementModelCapability Maturity Model (CMM) a standardizedframework for assessing the maturity level of anorganizations information system development andmanagement processes and products. It consists of fivelevels of maturity:
Level 1Initial: System development projects follow noprescribed process.
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Level 2Repeatable: Project management processes andpractices established to track project costs, schedules, andfunctionality.
Level 3Defined: Standard system development process(methodology) is purchased or developed. All projects use aversion of this process.
Level 4Managed: Measurable goals for quality andproductivity are established.
Level 5Optimizing: The standardized system developmentprocess is continuously monitored and improved based onmeasures and data analysis established in Level 4.
Information SystemDevelopment
Capability Maturity Model (CMM)
sebuah frame work (kerangka) untuk menilaitingkat kmatangan suatu organisasi dalam
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me a u an pengem angan s s em n ormas ,proses manajemen dan produk-produk.
level CMM
CMMterdiri dan lima level tingkat kematangan pengembangan:
1.level 1---Initial (Permulaan), Proyek pengembangan sistem tidakmengikuti proses yang konsisten
2.level 2--- Repeatable (Dapat diulang), Proses dan Pratek
manajemen proyek dibentuk untuk melacak biaya, jadwal, danfungsionalitas proyek
---
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. ,standar (disebut`metodologi) dibeli/dikembangkan4.level 4--- Managed (Terkelola), Tujuan-tujuan dapat diukur untukkualitas dan produktivitas dibentuk5.level 5---Optimized (Teroptimalisasi), Proses pengembangansistem terstandarisasi secara berkesinambungan dimonitor dandiperbaikiberdasarkan ukuran dan analisa data yang dibentuk di tkt
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Capability Maturity Model(CMM)
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Impact of System DevelopmentProcess on Quality
CMM Project Statistics for a Project Resulting in 200,000 Lines of Code
Organizations CMM Level
ProjectDuration
ProjectPerson-
Number ofDefects
MedianCost ($
LowestCost ($
HighestCost
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(months) Months Shipped millions) millions) ($ millions)
1 30 600 61 5.5 1.8 100+
2 18.5 143 12 1.3 .96 1.7
3 15 80 7 .728 .518 .933
DISKUSI :
Apakah setiap tahap dalam proses pengembangan
SI diselesaikan secara sekuensial? Jika ya, apa kekurangannya?
PROSES PENGEMBANGAN SI
Bagaimana mengatasi kekurangan tersebut?
OVERVIEW PROSES
Strategi pengembangan SI bisa berbentuk:
Sekuensial: metode Waterfall
Iteratif & incremental: Prototyping, Unified Process
Sekuensial:
Tiap tahap diselesaikan sebelum masuk tahapberikutnya (meskipun dlm praktek seringkali tahapsatu dengan lainnya overlap)
Kelemahan: pemilik dan pemakai tidak sabarmenunggu sistem jadi
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OVERVIEW PROSES
Iteratif dan incremental:
Analisis, rancang, implementasikansebagian. Lanjutkan analisis, rancang &
im lementasi seba ian la i. Lan utkan la ianalisis, rancang & implementasi, bagian
berikutnya. Demikian seterusnya sampai
sistem jadi
Kelebihan: meningkatkan kepuasan pemilikdan pemakai sistem
Life Cycle versus Methodology
System life cycle the factoring of the lifetime of an
information system into two stages, (1) systemsdevelopment and (2) systems operation andmaintenance.
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System development methodology a formalizedapproach to the systems development process; astandardized development process that defines (as inCMM Level 3) a set of activities, methods, best
practices, deliverables, and automated tools that systemdevelopers and project managers are to use to developand continuously improve information systems andsoftware.
System Life Cycle versus System DevelopmentMethodologies
System Life Cyclemembagi daur hidup sistem kedalam dua tahapan: (1) pengembangan sistemdan(2) operasidan support system
System Development Methodology adalah proses
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pengem angan s s em secara orma an epayang mendefinisikan serangkaian kegiatan,metode, best practices, keluaran dan suatu proses,dan tools automasi yang digunakan olehpengembang sistem yang digunakan untukmengembangkan sistem informasi
A System Life Cycle
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Representative SystemDevelopment Methodologies
Architected Rapid Application Development
(Architected RAD) Dynamic Systems Development Methodology
(DSDM)
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Joint Application Development (JAD)
Information Engineering (IE)
Rapid Application Development (RAD)
Rational Unified Process (RUP) Structured Analysis and Design
eXtreme Programming (XP)
Principles of SystemDevelopment Get the system users involved.
Use a problem-solving approach. Establish phases and activities.
Document through development.
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Establish standards.
Manage the process and projects
Justify systems as capital investments.
Dont be afraid to cancel or revise scope.
Divide and conquer.
Design systems for growth and change.
Prinsip-Prinsip Pengembangan Sistem
1.Melibatkan pemilik dan pengguna sistern.
2.Menggunakan pendekatan pemecahan maslah
3.Menuliskan tahapan- tahapan dan aktivitasnya.4.Menuliskan standarisasi
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5.Menjustifikasi sistem sebagai investasi modal
6.Jangan takut untuk mengubah ataumembatalkan lingkup kerja
7. Pecahkan dan taklukkan
8. Mendisain sistem untuk pengembangan danperubahan
TUGAS!!!
OVERVIEW PROSESPENGEMBANGAN SI
DISKUSI
Jika Anda punya masalah, bagaimana
langkah-langkah Anda untuk menyelesaikanmasalah tersebut?
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Use a Problem-SolvingApproachClassical Problem-solving approach
1. Study and understand the problem, its context,and its impact.
2. Define the requirements that must be meet by
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any so u on.
3. Identify candidate solutions that fulfill therequirements, and select the best solution.
4. Design and/or implement the chosen solution.5. Observe and evaluate the solutions impact, and
refine the solution accordingly.
Overview proses pengembangan SI vsProblem solving
Proses Pengembangan SIsederhana
Problem solving
Inisiasi/Perencanaan sistem 1. Identifikasi masalah (+rencana solusi)
Analisis sistem 2. Analisa & pahami masalah
3. Identifikasi solusi yg diharapkan
Desain Sistem 4. Identifikasi alternatif2 solusi & pilih
solusi yg tepat
5. Rancang solusi
Implementasi sistem 6. Implementasikan solusi
7. Evaluasi hasilnya
Perawatan & Pengembangan
sistem
Establish Phases and Activities
Overlap of System Development Phases
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Manage the Process andProjects
Process management an ongoing activity thatdocuments, manages, oversees the use of, and
improves an organizations chosen methodology (theprocess) for system development. Processmana ement is concerned with hases activities
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deliverables, and quality standards should beconsistently applied to all projects.
Project management is the process of scoping,planning, staffing, organizing, directing, and controlling
a project to develop an information system at aminimum cost, within a specified time frame, and withacceptable quality.
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Justify Information Systems asCapital InvestmentsCost-effectiveness The result obtained by striking abalance between the lifetime costs of developing, maintaining,and operating an information system and the benefits derivedfrom that system. Cost-effectiveness is measured by a cost-benefit analysis.
Strategic information systems plan a formal strategic plan
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(3-5 years) for building and improving an informationtechnology infrastructure and the information systemapplications that use that infrastructure.
Strategic enterprise plan a formal strategic plan (3-5 years)
for an entire business that defines its mission, vision, goals,strategies, benchmarks, and measures of progress andachievement. Usually, the strategic enterprise plan iscomplemented by strategic business unit plans that define howeach business unit will contribute to the enterprise plan. Theinformation systems plan is one of those unit-level plans.
Dont Be Afraid to Cancelor Revise Scope
Creeping commitment a strategy in which
feasibility and risks are continuously reevaluatedthroughout a project. Project budgets anddeadlines are adjusted accordingly.
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Risk management the process of identifying,evaluating, and controlling what might go wrongin a project before it becomes a threat to thesuccessful completion of the project orimplementation of the information system. Riskmanagement is drive by risk analysis orassessment.
Where Do Systems DevelopmentProjects Come From?
Problem an undesirable situation that
prevents the organization from fully achieving itspurpose, goals, and/or objectives.
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Opportunity a chance to improve the
organization even in the absence of anidentified problem.
Directive - a new requirement that is imposed
by management, government, or some externalinfluence.
Where Do Systems DevelopmentProjects Come From?
Problem Situasi tidak diinginkan yang
menghalangi organisasi untuk mencapai misi,visi,tujuan dan/atau sasaran.
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Opportunity Kesempatan untuk memperbaiki
organisasi bahkan saat problem teridentifikasitidak ada.
Directive persyaratan/permintaan baru yang
diberikan oleh manajemen, pemerintah, ataubeberapa pengaruh luar
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Masalah dan Peluang
Masalah adalah adanya suatu situasi yang
kurang menyenangkan yang menghalangi,organisasi untuk mencapai secara total tujuanorganisasi
Sebagai contoh, perusahaan
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mengidentifikasikan bahwa proses pesananpelanggan terlalu lama penanganannya. Proyeksistem informasi dapat dibuat mempercepatproses pesanan pelanggan sehingga lebih
responsif atau lebih cepat. Masalah bisa berupa masalah riil, ditengarai,atau diantisipasi.
Masalah dan Peluang
Peluang adalah suatu kesempatan untuk
melakukan peningkatan organisasi meskipuntidak ada yang spesifik dalamperusahaan tersebut.
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menerima ide untuk memotong/ mengurangibiaya, meskipun tidak ada masalah denganbiaya yang ada sekarang. Peluang melakukan
peningkatan/improvement adalah sumber dandimulainya proyek-proyek sistem informasi padamasa kini
Arahah/directive
Arahah/directiveadalah adanyakebutuhan baru yang diminta olhmanagement, pemerintah atau faktor-
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.
Misalnya adanya perubahan kebijakandan pemerintah mengenai PPh.
Where Do Systems DevelopmentProjects Come From?
Planned Projects
An information systems strategy plan hasexamined the business as a whole to identify those
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greatest strategic (long-term) value to the business
A business process redesign has thoroughlyanalyzed a series of business processes to eliminateredundancy and bureaucracy and to improve
efficiency and value added. Not it is time to redesignthe supporting information system for thoseredesigned business processes.
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Where Do Systems DevelopmentProjects Come From?
Unplanned projects
Triggered by a specific problem, opportunity, ordirective that occurs in the course of doing business.
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system owners and information technologyexecutives that prioritizes and approves candidatesystem development projects.
Backlog a repository of project proposals thatcannot be funded or staffed because they are a lowerpriority than those that have been approved forsystem development.
The PIECES Problem-SolvingFramework
P the need to improve performance
I the need to improve information (anddata)
E the need to improve economics, controlcos s, or ncrease pro s
C the need to improve control or security
E the need to improve efficiency of peopleand processes
S the need to improve service to customers,suppliers, partners, employees, etc.
Klasifikasikan masalah, James Wetherbe
Ia menyebutnya PIECESkarena tiap huruf punya artitersendiri.
P artinya kebutuhan untuk meningkatkan performance
I artin a kebutuhan untuk menin katkan information
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E artinya kebutuhan untuk meningkatkan economics,mengontrol biaya, atau meningkatkan keuntungan
C artinya kebutuhan untuk meningkatkan control
atau keamanan
E artinya kebutuhan untuk meningkatkari efficiency dan
orang-orang dan proses-proses S artinya kebutuhan untuk meningkatkan sen/cekepada
pelanggan, pemasok, partner, pegawai, dsb
Contoh Kasus
Pengembangan Sistem Informasi
Perpustakan X
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Contoh VISI MISI PerpustakaanX :
MISALKAN :
Visi :
Menjadi pusat penyedia bahan pustaka ilmu-ilmu komputer dansistem informasi yang lengkap, efektif, akurat dan handal sekotamalang.
Misi :
Meningkatkan minat akses masyarakat pada perpustakaan ini.
Menyediakan sumber bahan referensi ilmu-ilmu komputer dansistem informasi yang lenkap.
Tujuan :
Pertumbuhan anggota pertahun sebesar 10 % pertahun
Penigkatan akses anggota sebesar 2% perbulan Peningkatan sumber daya buku dan referensi sebesar 3 %perbulan
Identifikasi Masalah : Problems :
Dari tahun ke tahun jumlah anggota semakin merosot :
- fakta dilapangan (survey). Minat akses anggota menurun :
- fakta dilapangan (jumlah kehadiran diperpustakaan, jumlah peminjaman)
Sulit mencari informasi buku atau referensi an te at danakurat.
Opportunities : Kemudahan proses untuk menjadi anggota Kemudahaan proses peminjaman
Belum ada pesaing
Directives : Dukungan pemerintah mengkampanyekan minat baca.
Penyebab Masalah
Jumlah anggota merosot : Antara hak dan dan kewajiban tidak sepadan Persyaratan menjadi anggota terlalu ketat
Fasilitas anggota dan non anggota sama saja
Minat akses an ota menurun : Bahan perpustakaan out of date Proses peminjaman dilakukan secara manual
Sulit mencari informasi buku : Sistem katalog masih manual Tidak ada link ke pusat-pusat penyedia layanan yang lain
Analisa Penyebab dan PengaruhAnalisa Penyebab dan Pengaruh Tujuan Peningkatan SistemTujuan Peningkatan Sistem
MasalahMasalah Penyebab danPenyebab dan
PengaruhPengaruh
Tujuan SistemTujuan Sistem Batasan SistemBatasan Sistem
1. Dari tahun ke1. Dari tahun ketahun jumlahtahun jumlah
anggota semakinanggota semakin
Antara hak danAntara hak dandan kewajibandan kewajiban
tidak sepadantidak sepadan
PertumbuhanPertumbuhananggota pertahunanggota pertahun
sebesar 10 %sebesar 10 %
Sarana danSarana danprasana terbatasprasana terbatas
MATRIKS ANALISA MASALAH, PENYEBAB DANPENGARUH, TUJUAN DAN BATASAN
merosot :merosot : -- faktafakta
dilapangandilapangan
(survey).(survey).
PersyaratanPersyaratan
menjadi anggotamenjadi anggota
terlalu ketatterlalu ketat
FasilitasFasilitas
anggota dan nonanggota dan non
anggota samaanggota sama
sajasaja
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en as masa a erang aPIECESDari SIP X diusulkan solusi memenuhi kerangka :
P : Pencapaian tujuan yang ditetapkan
I : Mudah mencari informasi referensi buku
E : Peningkatan sumber pendanaan.
E : Efisiensi tenaga kerja, dan sumber daya yang lain
S : Peningkatan kemudahan anggota melakukan transaksipeminjaman dan pengembalian.
Performance Information Economic Controlling EficiencyService
Solusi yang ditawarkan
Berdasarkan kerangka PIECES :
Perlunya dikembangkan sistem informasi perpustakanberbasis komputer yang mampu memberikanpeningkatan layanan pada anggota dan memberikan
menejemen.
(Tidak semua permasalahan diambil, hanya I, C, S)
Project Phases
FAST - (Framework for the Application of SystemsThinking ) a hypothetical methodology usedthroughout this book to demonstrate a representativesystems development process.
Each methodology will use different project phases.
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ProjectInitiation
SystemAnalysis
SystemDesign
SystemImplementation
Scope Definition X
Problem Analysis X X
Requirements Analysis X
Logical Design X
Decision Analysis (a system analysis transition phase)Physical Design and Integration X
Construction and Testing X X
Installation and Delivery X
ramewor or t e pp cat onof SystemTechniques).
Identifikasi Proyek
Seperti pemicu karena peluang
-
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orang yang memulai inisiatif pada kebanyakariproyek.
Seperti yang terlihat pada gambar pemicu adanya
suatu proyek biasanya karena adanya suatumasalah, peluang dan arahan/directives
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Masalah dan Peluang
Masalah adalah adanya suatu situasi yang
kurang menyenangkan yang menghalangi,organisasi untuk mencapai secara total tujuanorganisasi
Sebagai contoh, perusahaan
45
mengidentifikasikan bahwa proses pesananpelanggan tenlalu lama penanganannya.Proyek sistem informasi dapat dibuatmempercepat proses pesanan pelanggan
sehingga lebih responsif atau lebih cepat. Masalah bisa berupa masalah riil, ditengarai,atau diantisipasi.
Masalah dan Peluang
Peluang adalah suatu kesempatan untuk
melakukan peningkatan organisasi meskipuntidak ada yang spesifik dalamperusahaan tersebut.
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menerima ide untuk memotong/ mengurangibiaya, meskipun tidak ada masalah denganbiaya yang ada sekarang. Peluang melakukan
peningkatan/improvement adalah sumber dandimulainya proyek-proyek sistem informasi padamasa kini
Arahah/directive
Arahah/directiveadalah adanyakebutuhan baru yang diminta olh
management, pemenintah atau faktor-
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.
Misalnya adanya perubahan kebijakandan pemerintah mengenai PPh.
Tahapan-tahapan pro yek
Metodologi FAST mendukung kedua tahapanpengembangan sistemdan operasi dan supportdari daurhidup pengembangan sistem.
Tahapan-tahapan proyek pengembangan sistem:1.Investigasi awal
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.3.Analisa kebutuhan4.Analisa pengambilan keputusan5.Disain6.Konstruksi7.Implmentasi
8.Operasi dan Support
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FAST Project Phases
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Building Blocks View ofSystem Development
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Scope Definition Phase
Problem statement a statement and categorization ofproblems, opportunities, and directives; may also includeconstraints and an initial vision for the solution. Synonymsinclude preliminary studyand feasibility assessment.
Constraint any factor, limitation, or restraint that may limit asolution or the problem-solving process.
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Scope creep a common phenomenon wherein therequirements and expectations of a project increase, oftenwithout regard to the impact on budget and schedule.
Statement of work a contract with management and theuser community to develop or enhance an information system;
defines vision, scope, constraints, high-level userrequirements, schedule, and budget. Synonyms includeproject charter, project plan, and service-level agreement.
Requirements Analysis Phase
What capabilities should the new systemprovide for its users?
What data must be captured and stored?
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a per ormance eve s expec e
What are the priorities of the variousrequirements?
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Logical Design Phase
Logical design the translation of business user requirementsinto a system model that depicts only the business requirements
and not any possible technical design or implementation ofthose requirements. Common synonyms include conceptualdesignand essential design.
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ystem mo e a p cture o a system t at represents rea ty ora desired reality. System models facilitate improvedcommunication between system users, system analysts, systemdesigners, and system builders.
Analysis paralysis a satirical term coined to describe acommon project condition in which excessive system modelingdramatically slows progress toward implementation of theintended system solution.
Decision Analysis Phase
Candidate solutions evaluated in terms of:
Technical feasibility Is the solution technically practical?Does our staff have the technical expertise to design and buildthis solution?
Operational feasibility Will the solution fulfill the users
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requ remen s o w a egree ow w e so u on c angethe users work environment? How do users feel about such asolution?
Economic feasibility Is the solution cost-effective?
Schedule feasibility Can the solution be designed and
implemented within an acceptable time?
Risk feasibility What is the probability of a successfulimplementation using the technology and approach?
Physical Design & IntegrationPhase
Physical design the translation of business user requirementsinto a system model that depicts a technical implementation ofthe users business requirements. Common synonyms include
technical designor implementation model.
Two extreme hiloso hies of h sical desi n
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Design by specification physical system models and detailedspecification are produced as a series of written (or computer-generated) blueprints for construction.
Design by prototyping Incomplete but functioning applications orsubsystems (called prototypes) are constructed and refined based
on feedback from users and other designers.
Construction and Testing Phase
Construct and test system components
Software
Purchased
Custom-built
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Databases
User and System Interfaces
Hardware
Networks
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Installation and Delivery Phase
Deliver the system into operation
(production)
Deliver User training
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e ver comp e e ocumen a on
Convert existing data
System Operation &Maintenance
System support the ongoing technical
support for users of a system, as well asthe maintenance required to deal with any
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, ,that may arise.
Cross Life-Cycle Activities
Cross life-cycle activity activities that overlapmultiple phases
Fact-finding - formal process of using research,interviews, meetings, questionnaires, sampling, andother techniques to collect information about systemproblems, requirements,and preferences.
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ocumen a on an presen a on Documentation recording facts and specifications for a
systems for current and future reference. Presentation communicating findings, recommendations,
and documentation for review by interested users andmangers.
Repository database and/or file directory where system
developers store all documentation, knowledge, andartifacts for information systems or project(s).
Feasibility analysis Process and project management
System Development Documentation,Repository, and Presentations
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Sequential versus IterativeDevelopmentWaterfall developmentapproach an approach tosystems analysis and designthat completes each phase oneafter another and only once .
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approach an approach tosystems analysis and designthat completes the entireinformation system insuccessive iterations. Each
iterations does some analysis,some design, and someconstruction. Synonyms includeincremental and spiral.
A Taxonomy for System DevelopmentMethodologies & Strategies
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Model-Driven DevelopmentStrategy
Model-driven development a system developmentstrategy that emphasizes the drawing of system modelsto help visualize and analyze problems, define businessrequirements, and design information systems.
Process modeling a process-centered technique popularizedby the structured analysis and design methodology that used
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mo e s o us ness process requ remen s o er ve e ec vesoftware designs for a system.
Data modeling a data-centered technique used to modelbusiness data requirements and design database systems thatfulfill those requirements.
Object modeling a technique that attempts to merge the dataand process concerns into singular constructs called objects.Object models are diagrams that document a system in terms ofits objects and their interactions.
Logical vs. Physical Models
Logical model - a pictorial representationthat depicts what a system is or does.
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ys ca mo e - a ec n ca p c or arepresentation that depicts what a system isor does and how the system isimplemented.
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Model-Driven DevelopmentStrategy
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Model-Driven DevelopmentStrategy
Requirements oftenmore thorough
Easier to analyze
Time consuming Models only as good
as users'
Advantages Disadvantages
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a erna ves
Design specificationsoften more stable and
flexible
Systems can be
constructed morecorrectly the first time
un ers an ng o
requirements
Reduces users' role
because pictures arenot software
Can be Inflexible
Rapid Application DevelopmentStrategy Rapid application development (RAD) a system
development strategy that emphasizes speed ofdevelopment through extensive user involvement in the
rapid, iterative, and incremental construction of series offunctioning prototypes of a system that eventuallyevolves into the final s stem.
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Prototype a small-scale, representative, or working model ofthe users requirements or a proposed design for aninformation system.
Time box the imposition of a non-extendable period of time,usually 60-90 days, by which the first (or next) version of asystem must be delivered into operation.
Rapid Application DevelopmentStrategy
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Rapid Application DevelopmentStrategy
User requirements oftenuncertain or imprecise
Encourages active user andmanagement participation
May encourage "code,implement, repair" mentality
Can solve wrong problemsince problem analysis is
Advantages Disadvantages
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and support
Stakeholders see workingsolutions more rapidly
Errors detected earlier
Testing and training arenatural by-products
More natural process becausechange is expected
May discourage analysts fromconsidering alternatives
Stakeholders reluctant tothrow away prototype
Emphasis on speed can
adversely impact quality
Commercial Application PackageImplementation Strategy Commercial application package software
application that can be purchased and customized tomeet business requirements of a large number of
organizations or specific industry. A synonym iscommercial off-the-shelf(COTS) system.
Request for proposal (RFP) formal document thatcommunicates business technical and su ort re uirements
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for application software package to vendors that may wish tocompete for the sale of application package and services.
Request for quotation (RFQ) formal document thatcommunicates business, technical, and support requirementsfor an application software package to a single vendor thathas been determined as being able to supply that applicationpackage and services.
Gap analysis comparison of business and technicalrequirements for a commercial application package againstcapabilities and features of a specific commercial applicationpackage to define requirements that cannot be met.
Commercial Application PackageImplementation Strategy
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Commercial Application PackageImplementation Strategy
Systems usually implemented
more quickly Avoids staffing required to
develo in-house solutions
Dependent on long-term
viability of vendor Rarely reflects ideal solution
Advantages Disadvantages
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Generally less expensive
Vendor assumes responsibilityfor improvements andcorrections
Many business functions moresimilar than dissimilar for allbusinesses in a given industry
business processes to adaptto software
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Hybrid Strategies
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A System MaintenancePerspective
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Automated Tools andTechnology
Computer-aided systems engineering
(CASE)
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(ADEs)
Process and project managers
Computer-Assisted SoftwareEngineering (CASE)Computer-aided systems engineering (CASE) automated software tools that support the drawing andanalysis of system models and associated specifications.Some CASE tools also provide prototyping and code
generation capabilities. CASE repository system developers database where
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,descriptions and specifications, and other products ofsystem development. Synonyms: dictionaryandencyclopedia.
Forward engineering CASE tool capability that cangenerate initial software or database code directly fromsystem.
Reverse engineering CASE tool capability that cangenerate initial system models from software ordatabase code.
U i CASE T l f S
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Using a CASE Tool for SystemDevelopment
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CASE Tool Architecture
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Application DevelopmentEnvironments
Application development environments (ADEs) anintegrated software development tool that provides all the
facilities necessary to develop new application softwarewith maximum speed and quality. A common synonym isinte rated develo ment environment IDE
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ADE facilities may include:
Programming languages or interpreters
Interface construction tools
Middleware
Testing tools
Version control tools
Help authoring tools
Repository links
Process and Project Managers
Process manager application an automated tool thathelps document and manage a methodology and routes,
its deliverables, and quality management standards. Anemerging synonym is methodware.
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Project manager application an automated tool tohelp plan system development activities (preferably usingthe approved methodology), estimate and assignresources (including people and costs), scheduleactivities and resources, monitor progress againstschedule and budget, control and modify schedule and
resources, and report project progress.