SlideShare uma empresa Scribd logo
1 de 9
Baixar para ler offline
CompSci 230
Software Construction
Lecture Slides #24: Waterfall Development S1 2016
Agenda
CompSci 230: WF
2
 Topics:
 The Waterfall model of software development
 Testing under waterfall
 Pros and cons of waterfall development
The “waterfall” model
CompSci 230: WF
3
 Dates back to 1968!
 Models software development as a linear multi-stage
manufacturing process
 Linear: stages follow distinctly after each other, each stage feeds
into the next stage only, any iterations and feedback happen within
each stage only
 Each stage must be completed before the start of the next
stage
 Each stage is verified against the previous stage and then signed
off
 No stage is complete without sign-off
 Think of a waterfall tumbling down over several stages
 Water flows downhill only
Stages of the waterfall process
CompSci 230: WF
4
1. Decision stage
a) Develop the business case
b) Gather user requirements
c) Write system specification (generally an SRS)
2. Design stage
a) System design
b) Component design
3. Development stage
a) Build the components
4. Demonstration stage
a) Testing
Order
of
implementation
Features, pros and cons of waterfall
CompSci 230: WF
5
 Each stage requires specific specialised skills (business
analyst, system architect, developer, tester)
 Documentation plays a key role
 Stages can take a long time to implement
 Requirements may change during this period
 Resulting product may not be what is needed
Testing in waterfall
CompSci 230: WF
6
 Testing mirrors the (sub)stages, in reverse order
 Stage / Test:
 Component test: (unit test) verifies against component design
 Performed by developer or independent tester as white or black box test
 Challenges: see black box / white box testing
 Interface test (integration test): verifies against system design
 Performed by developer(s) or independent tester
 Challenges: is understanding of interfaces correct? Tests of this type tend to throw up a lot of
issues.
 System test: verifies against system specification
 Performed by dedicated tester(s)
 Challenges: Ideally ought to be done in a production-like environment, which is difficult to
establish for testing only
 Acceptance test: verifies against user requirements
 Performed by customer or dedicated tester(s)
 Challenges: Ideally ought to be done in user environment, which can be difficult to establish
for testing only
 Release test: verifies against business case
 Performed by customer and or specialised operations team in live environment
 Challenges: business risk of failures becoming apparent at this stage
Other types of testing
CompSci 230: WF
7
 Portability testing
 Generally done by code inspection (at component test level) or during integration /
system testing as black box tests
 Challenges: tends to throw up a lot of issues requiring significant additional
development work
 Smoke testing
 Superficial test of system before handover for proper system test to catch obvious
faults
 Usability testing
 Performed with the help of users to see how quickly users learn and operate the
system
 Load testing: ensure system can cope with expected maximum load.
 Challenges: replicating behavior of a large number of users, replicating physical
environment (latency & bandwidth constraints)
 Stress testing: load testing to determine the maximum load that the system is able to
support
 Regression testing
 Used during component, interface and system test to ensure changes to a previous
version don’t break functionality
Waterfall - challenges
CompSci 230: WF
8
 Non-overlapping nature of stages and tests means projects
tend to take a long time
 Needs of stakeholders change over time
 What gets built may not be the right thing
 Reliance on documentation means that a large amount of
documentation needs to be managed
 Documents are difficult to keep up to date and consistent
 Documentation doesn’t capture informal knowledge of the actors in
the various stages
 E.g., SRS contains lots of detail but may be relatively brief on “big picture”
stuff because it requires domain knowledge, which developers may not
have. So developers may fail to see the forest for the trees.
Review
CompSci 230: WF
9
 Which are the stages of the waterfall model?
 Which types of testing correspond to these stages?
 Name a few reasons that cause projects following the
waterfall model to take a long time
 What are the advantages and risks of the waterfall model?

Mais conteúdo relacionado

Semelhante a 25Waterfall.pptx

Software Development Life Cycle Testingtypes
Software Development Life Cycle TestingtypesSoftware Development Life Cycle Testingtypes
Software Development Life Cycle Testingtypesvladimir zaremba
 
Waterfall models.ppt
Waterfall models.pptWaterfall models.ppt
Waterfall models.pptPawanRaj48
 
[2015/2016] Software development process
[2015/2016] Software development process[2015/2016] Software development process
[2015/2016] Software development processIvano Malavolta
 
15 si(systems analysis and design )
15 si(systems analysis and design )15 si(systems analysis and design )
15 si(systems analysis and design )Nurdin Al-Azies
 
Bba ii cam u iii-introduction to sdlc cycle
Bba ii cam  u iii-introduction to sdlc cycleBba ii cam  u iii-introduction to sdlc cycle
Bba ii cam u iii-introduction to sdlc cycleRai University
 
Types of software life cycle model
Types of software life cycle model Types of software life cycle model
Types of software life cycle model Santhia RK
 
Software development PROCESS
Software development PROCESSSoftware development PROCESS
Software development PROCESSIvano Malavolta
 
UVM_Full_Print_n.pptx
UVM_Full_Print_n.pptxUVM_Full_Print_n.pptx
UVM_Full_Print_n.pptxnikitha992646
 
Slides1 - testing
Slides1 - testingSlides1 - testing
Slides1 - testingJyothi Vbs
 
Keynote VST2020 (Workshop on Validation, Analysis and Evolution of Software ...
Keynote VST2020 (Workshop on  Validation, Analysis and Evolution of Software ...Keynote VST2020 (Workshop on  Validation, Analysis and Evolution of Software ...
Keynote VST2020 (Workshop on Validation, Analysis and Evolution of Software ...University of Antwerp
 
Sdlc cource in_mumbai
Sdlc cource in_mumbaiSdlc cource in_mumbai
Sdlc cource in_mumbaivibrantuser
 
Sen2 Software Processes
Sen2 Software ProcessesSen2 Software Processes
Sen2 Software ProcessesMatzeAtFontys
 
DevOps and Build Automation
DevOps and Build AutomationDevOps and Build Automation
DevOps and Build AutomationHeiswayi Nrird
 

Semelhante a 25Waterfall.pptx (20)

Software Development Life Cycle Testingtypes
Software Development Life Cycle TestingtypesSoftware Development Life Cycle Testingtypes
Software Development Life Cycle Testingtypes
 
Model.ppt
Model.pptModel.ppt
Model.ppt
 
chapter 2 (1).ppt
chapter 2 (1).pptchapter 2 (1).ppt
chapter 2 (1).ppt
 
Waterfall models.ppt
Waterfall models.pptWaterfall models.ppt
Waterfall models.ppt
 
[2015/2016] Software development process
[2015/2016] Software development process[2015/2016] Software development process
[2015/2016] Software development process
 
15 si(systems analysis and design )
15 si(systems analysis and design )15 si(systems analysis and design )
15 si(systems analysis and design )
 
SDLC
SDLC SDLC
SDLC
 
Bba ii cam u iii-introduction to sdlc cycle
Bba ii cam  u iii-introduction to sdlc cycleBba ii cam  u iii-introduction to sdlc cycle
Bba ii cam u iii-introduction to sdlc cycle
 
Types of software life cycle model
Types of software life cycle model Types of software life cycle model
Types of software life cycle model
 
Software development PROCESS
Software development PROCESSSoftware development PROCESS
Software development PROCESS
 
UVM_Full_Print_n.pptx
UVM_Full_Print_n.pptxUVM_Full_Print_n.pptx
UVM_Full_Print_n.pptx
 
Slides1 - testing
Slides1 - testingSlides1 - testing
Slides1 - testing
 
Keynote VST2020 (Workshop on Validation, Analysis and Evolution of Software ...
Keynote VST2020 (Workshop on  Validation, Analysis and Evolution of Software ...Keynote VST2020 (Workshop on  Validation, Analysis and Evolution of Software ...
Keynote VST2020 (Workshop on Validation, Analysis and Evolution of Software ...
 
Sdlc cource in_mumbai
Sdlc cource in_mumbaiSdlc cource in_mumbai
Sdlc cource in_mumbai
 
Gatehouse software genanvendelse
Gatehouse software genanvendelseGatehouse software genanvendelse
Gatehouse software genanvendelse
 
2.SDLC Models.ppt
2.SDLC Models.ppt2.SDLC Models.ppt
2.SDLC Models.ppt
 
Sen2 Software Processes
Sen2 Software ProcessesSen2 Software Processes
Sen2 Software Processes
 
DevOps and Build Automation
DevOps and Build AutomationDevOps and Build Automation
DevOps and Build Automation
 
Sdlc
SdlcSdlc
Sdlc
 
01lifecycles
01lifecycles01lifecycles
01lifecycles
 

Último

Integrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptx
Integrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptxIntegrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptx
Integrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptxgarusoumyadeep617
 
Gujrat BCAsem6ShellScript-Practicles.pdf
Gujrat BCAsem6ShellScript-Practicles.pdfGujrat BCAsem6ShellScript-Practicles.pdf
Gujrat BCAsem6ShellScript-Practicles.pdfRajeshPatel136226
 
Nam Pham - Resume for Digital Portfolio Assignment
Nam Pham - Resume for Digital Portfolio AssignmentNam Pham - Resume for Digital Portfolio Assignment
Nam Pham - Resume for Digital Portfolio Assignmentphuongpham070189
 
Technical Skills covering DSA and Lead Application
Technical Skills covering DSA and Lead ApplicationTechnical Skills covering DSA and Lead Application
Technical Skills covering DSA and Lead ApplicationVISHNURAJSSNSCEAD
 
INTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdf
INTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdfINTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdf
INTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdfLouis Malaybalay
 
A Guide to a Winning Interview March 2024
A Guide to a Winning Interview March 2024A Guide to a Winning Interview March 2024
A Guide to a Winning Interview March 2024Bruce Bennett
 
How Job Apps Are Fastly Transforming Careers?
How Job Apps Are  Fastly Transforming Careers?How Job Apps Are  Fastly Transforming Careers?
How Job Apps Are Fastly Transforming Careers?SnapJob
 
Spring 2024 Storyboard Project: Maria Rough Boards
Spring 2024 Storyboard Project: Maria Rough BoardsSpring 2024 Storyboard Project: Maria Rough Boards
Spring 2024 Storyboard Project: Maria Rough BoardsSophieJones152612
 
Preparation Guide: IBM C1000-127 Certification | Crack Exam | Sample Questions
Preparation Guide: IBM C1000-127 Certification | Crack Exam | Sample QuestionsPreparation Guide: IBM C1000-127 Certification | Crack Exam | Sample Questions
Preparation Guide: IBM C1000-127 Certification | Crack Exam | Sample QuestionsKatyMorgan10
 
GMAT.ppt presentation for career counselling
GMAT.ppt presentation for career counsellingGMAT.ppt presentation for career counselling
GMAT.ppt presentation for career counsellingRaj Tomar
 
SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.
SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.
SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.Sharon Liu
 
Session on Responsible Tourism and Entertainment Park.pdf
Session on Responsible Tourism and Entertainment Park.pdfSession on Responsible Tourism and Entertainment Park.pdf
Session on Responsible Tourism and Entertainment Park.pdfMd Shaifullar Rabbi
 
World’s Best Visionary Leaders to Follow in 2024.pdf
World’s Best Visionary Leaders to Follow in 2024.pdfWorld’s Best Visionary Leaders to Follow in 2024.pdf
World’s Best Visionary Leaders to Follow in 2024.pdfeducationviewindia1
 
Ken Kremsky's Professional Career and Specializations are Outstanding
Ken Kremsky's Professional Career and Specializations are OutstandingKen Kremsky's Professional Career and Specializations are Outstanding
Ken Kremsky's Professional Career and Specializations are OutstandingKennethKremsky
 
Gujrat University bca sem 6SHELL MAIN.pdf
Gujrat University bca sem 6SHELL MAIN.pdfGujrat University bca sem 6SHELL MAIN.pdf
Gujrat University bca sem 6SHELL MAIN.pdfRajeshPatel136226
 
Thomas K Girard, Resume, Vancouver, March 2024
Thomas K Girard, Resume, Vancouver, March 2024Thomas K Girard, Resume, Vancouver, March 2024
Thomas K Girard, Resume, Vancouver, March 2024Thomas GIRARD BDes
 
Boss Your Career - Negotiate Your Rate .pdf
Boss Your Career - Negotiate Your Rate .pdfBoss Your Career - Negotiate Your Rate .pdf
Boss Your Career - Negotiate Your Rate .pdfPamella Bisson
 
Thomas K Girard, Curriculum Vitae, India, March 2024
Thomas K Girard, Curriculum Vitae, India, March 2024Thomas K Girard, Curriculum Vitae, India, March 2024
Thomas K Girard, Curriculum Vitae, India, March 2024Thomas GIRARD BDes
 
January 2024 Personal Comic Project: New Year
January 2024 Personal Comic Project: New YearJanuary 2024 Personal Comic Project: New Year
January 2024 Personal Comic Project: New YearSophieJones152612
 

Último (20)

Integrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptx
Integrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptxIntegrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptx
Integrated Paddy-Cum-Fish Culture 19.2.2022 PDF.pptx
 
Gujrat BCAsem6ShellScript-Practicles.pdf
Gujrat BCAsem6ShellScript-Practicles.pdfGujrat BCAsem6ShellScript-Practicles.pdf
Gujrat BCAsem6ShellScript-Practicles.pdf
 
Nam Pham - Resume for Digital Portfolio Assignment
Nam Pham - Resume for Digital Portfolio AssignmentNam Pham - Resume for Digital Portfolio Assignment
Nam Pham - Resume for Digital Portfolio Assignment
 
BCA sem 6. All Program.pdf
BCA sem 6.                All Program.pdfBCA sem 6.                All Program.pdf
BCA sem 6. All Program.pdf
 
Technical Skills covering DSA and Lead Application
Technical Skills covering DSA and Lead ApplicationTechnical Skills covering DSA and Lead Application
Technical Skills covering DSA and Lead Application
 
INTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdf
INTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdfINTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdf
INTRODUCE YOURSELF PPT - WRETMAN - LOUIS MALAYBALAY.pdf
 
A Guide to a Winning Interview March 2024
A Guide to a Winning Interview March 2024A Guide to a Winning Interview March 2024
A Guide to a Winning Interview March 2024
 
How Job Apps Are Fastly Transforming Careers?
How Job Apps Are  Fastly Transforming Careers?How Job Apps Are  Fastly Transforming Careers?
How Job Apps Are Fastly Transforming Careers?
 
Spring 2024 Storyboard Project: Maria Rough Boards
Spring 2024 Storyboard Project: Maria Rough BoardsSpring 2024 Storyboard Project: Maria Rough Boards
Spring 2024 Storyboard Project: Maria Rough Boards
 
Preparation Guide: IBM C1000-127 Certification | Crack Exam | Sample Questions
Preparation Guide: IBM C1000-127 Certification | Crack Exam | Sample QuestionsPreparation Guide: IBM C1000-127 Certification | Crack Exam | Sample Questions
Preparation Guide: IBM C1000-127 Certification | Crack Exam | Sample Questions
 
GMAT.ppt presentation for career counselling
GMAT.ppt presentation for career counsellingGMAT.ppt presentation for career counselling
GMAT.ppt presentation for career counselling
 
SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.
SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.
SL CV 20240312.docx . Sharon Xiao Liu's Curriculum Vitae.
 
Session on Responsible Tourism and Entertainment Park.pdf
Session on Responsible Tourism and Entertainment Park.pdfSession on Responsible Tourism and Entertainment Park.pdf
Session on Responsible Tourism and Entertainment Park.pdf
 
World’s Best Visionary Leaders to Follow in 2024.pdf
World’s Best Visionary Leaders to Follow in 2024.pdfWorld’s Best Visionary Leaders to Follow in 2024.pdf
World’s Best Visionary Leaders to Follow in 2024.pdf
 
Ken Kremsky's Professional Career and Specializations are Outstanding
Ken Kremsky's Professional Career and Specializations are OutstandingKen Kremsky's Professional Career and Specializations are Outstanding
Ken Kremsky's Professional Career and Specializations are Outstanding
 
Gujrat University bca sem 6SHELL MAIN.pdf
Gujrat University bca sem 6SHELL MAIN.pdfGujrat University bca sem 6SHELL MAIN.pdf
Gujrat University bca sem 6SHELL MAIN.pdf
 
Thomas K Girard, Resume, Vancouver, March 2024
Thomas K Girard, Resume, Vancouver, March 2024Thomas K Girard, Resume, Vancouver, March 2024
Thomas K Girard, Resume, Vancouver, March 2024
 
Boss Your Career - Negotiate Your Rate .pdf
Boss Your Career - Negotiate Your Rate .pdfBoss Your Career - Negotiate Your Rate .pdf
Boss Your Career - Negotiate Your Rate .pdf
 
Thomas K Girard, Curriculum Vitae, India, March 2024
Thomas K Girard, Curriculum Vitae, India, March 2024Thomas K Girard, Curriculum Vitae, India, March 2024
Thomas K Girard, Curriculum Vitae, India, March 2024
 
January 2024 Personal Comic Project: New Year
January 2024 Personal Comic Project: New YearJanuary 2024 Personal Comic Project: New Year
January 2024 Personal Comic Project: New Year
 

25Waterfall.pptx

  • 1. CompSci 230 Software Construction Lecture Slides #24: Waterfall Development S1 2016
  • 2. Agenda CompSci 230: WF 2  Topics:  The Waterfall model of software development  Testing under waterfall  Pros and cons of waterfall development
  • 3. The “waterfall” model CompSci 230: WF 3  Dates back to 1968!  Models software development as a linear multi-stage manufacturing process  Linear: stages follow distinctly after each other, each stage feeds into the next stage only, any iterations and feedback happen within each stage only  Each stage must be completed before the start of the next stage  Each stage is verified against the previous stage and then signed off  No stage is complete without sign-off  Think of a waterfall tumbling down over several stages  Water flows downhill only
  • 4. Stages of the waterfall process CompSci 230: WF 4 1. Decision stage a) Develop the business case b) Gather user requirements c) Write system specification (generally an SRS) 2. Design stage a) System design b) Component design 3. Development stage a) Build the components 4. Demonstration stage a) Testing Order of implementation
  • 5. Features, pros and cons of waterfall CompSci 230: WF 5  Each stage requires specific specialised skills (business analyst, system architect, developer, tester)  Documentation plays a key role  Stages can take a long time to implement  Requirements may change during this period  Resulting product may not be what is needed
  • 6. Testing in waterfall CompSci 230: WF 6  Testing mirrors the (sub)stages, in reverse order  Stage / Test:  Component test: (unit test) verifies against component design  Performed by developer or independent tester as white or black box test  Challenges: see black box / white box testing  Interface test (integration test): verifies against system design  Performed by developer(s) or independent tester  Challenges: is understanding of interfaces correct? Tests of this type tend to throw up a lot of issues.  System test: verifies against system specification  Performed by dedicated tester(s)  Challenges: Ideally ought to be done in a production-like environment, which is difficult to establish for testing only  Acceptance test: verifies against user requirements  Performed by customer or dedicated tester(s)  Challenges: Ideally ought to be done in user environment, which can be difficult to establish for testing only  Release test: verifies against business case  Performed by customer and or specialised operations team in live environment  Challenges: business risk of failures becoming apparent at this stage
  • 7. Other types of testing CompSci 230: WF 7  Portability testing  Generally done by code inspection (at component test level) or during integration / system testing as black box tests  Challenges: tends to throw up a lot of issues requiring significant additional development work  Smoke testing  Superficial test of system before handover for proper system test to catch obvious faults  Usability testing  Performed with the help of users to see how quickly users learn and operate the system  Load testing: ensure system can cope with expected maximum load.  Challenges: replicating behavior of a large number of users, replicating physical environment (latency & bandwidth constraints)  Stress testing: load testing to determine the maximum load that the system is able to support  Regression testing  Used during component, interface and system test to ensure changes to a previous version don’t break functionality
  • 8. Waterfall - challenges CompSci 230: WF 8  Non-overlapping nature of stages and tests means projects tend to take a long time  Needs of stakeholders change over time  What gets built may not be the right thing  Reliance on documentation means that a large amount of documentation needs to be managed  Documents are difficult to keep up to date and consistent  Documentation doesn’t capture informal knowledge of the actors in the various stages  E.g., SRS contains lots of detail but may be relatively brief on “big picture” stuff because it requires domain knowledge, which developers may not have. So developers may fail to see the forest for the trees.
  • 9. Review CompSci 230: WF 9  Which are the stages of the waterfall model?  Which types of testing correspond to these stages?  Name a few reasons that cause projects following the waterfall model to take a long time  What are the advantages and risks of the waterfall model?