This document discusses software life cycle models, including the waterfall, incremental, evolutionary (prototyping), and spiral models. It describes the common phases of software development like requirements, design, implementation, testing, deployment, and maintenance. The waterfall model is a traditional sequential approach, while other models allow for more iterative development and flexibility. Selection of the appropriate model depends on factors like the project and level of risk.
This document outlines the software development lifecycle process. It involves planning with risk analysis, requirements validation, design, and verification. Prototypes are developed and tested at the unit, integration, and acceptance levels. Reviews are conducted at each phase to evaluate alternatives, identify and resolve risks, and plan for the next phase of the project lifecycle.
This document discusses various models of the software development process including waterfall, prototyping, V-model, spiral model, and phased development. It explains the key characteristics and phases of each model. The waterfall model is presented as a sequential process while later models incorporate more iterative and overlapping elements to better reflect the realities of software development. Process modeling and different approaches are also covered at a high level.
The document discusses several software development lifecycle models, including build and fix, waterfall, incremental, rapid prototyping, spiral, and object oriented models. It provides brief descriptions of each model's phases and process. The waterfall model is described as the first published model, involving sequential phases of requirements, design, implementation, integration, and maintenance. However, it notes waterfall has limitations in responding to changing requirements. Rapid prototyping is used to help capture user requirements through a mock application. The incremental model delivers functionality in increments to get early feedback. Spiral model adds risk analysis before each phase. Object oriented models incorporate iteration, parallelism and incremental development.
Agile testing is a software testing practice that follows the principles of agile software development. In agile testing, testing is continuous and occurs throughout the development process rather than as a separate phase. All team members, including developers and business analysts, are involved in testing. Feedback is provided frequently in short iterations to quickly adapt to changing requirements. This allows issues to be identified and addressed earlier compared to traditional waterfall development models.
The document introduces software process models including the waterfall model, evolutionary development, and component-based software engineering. It describes the Rational Unified Process model and discusses key process activities like requirements engineering, design, implementation, testing, and evolution. Computer-aided software engineering tools are introduced as a way to support various activities in the software development process.
The document compares various software development life cycle (SDLC) models, including the waterfall model, spiral model, prototype model, and iterative model. It discusses the advantages and limitations of each model. The waterfall model is simple and easy to understand but cannot accommodate changing requirements. The spiral model emphasizes risk analysis but can be costly. The prototype model involves user feedback early but risks wasted time if the prototype is rejected. The iterative model allows for changes between iterations but requires more management attention. In conclusion, the best model depends on the project's characteristics and needs.
The document discusses different software development life cycle (SDLC) models including the waterfall model, spiral model, and agile model. It provides an overview of each model's phases, advantages, and disadvantages. The waterfall model is the oldest and most widely used. It is linear but can lead to confusion if requirements are unclear. The spiral model is adapted for large, complicated projects and allows for changes and testing at each phase but requires an experienced team. The agile model prioritizes requirements, verification, design, and implementation through iterative development with customer involvement and fixed time periods.
This document discusses various software development life cycle (SDLC) models including waterfall, iterative waterfall, rapid prototype, evolutionary, spiral, fish, V-shape, RAD, and incremental models. For each model, it provides a brief description and highlights the advantages and disadvantages. The models differ in their structure, approach to requirements, testing, flexibility, and ability to handle risk and changing requirements.
This document outlines the software development lifecycle process. It involves planning with risk analysis, requirements validation, design, and verification. Prototypes are developed and tested at the unit, integration, and acceptance levels. Reviews are conducted at each phase to evaluate alternatives, identify and resolve risks, and plan for the next phase of the project lifecycle.
This document discusses various models of the software development process including waterfall, prototyping, V-model, spiral model, and phased development. It explains the key characteristics and phases of each model. The waterfall model is presented as a sequential process while later models incorporate more iterative and overlapping elements to better reflect the realities of software development. Process modeling and different approaches are also covered at a high level.
The document discusses several software development lifecycle models, including build and fix, waterfall, incremental, rapid prototyping, spiral, and object oriented models. It provides brief descriptions of each model's phases and process. The waterfall model is described as the first published model, involving sequential phases of requirements, design, implementation, integration, and maintenance. However, it notes waterfall has limitations in responding to changing requirements. Rapid prototyping is used to help capture user requirements through a mock application. The incremental model delivers functionality in increments to get early feedback. Spiral model adds risk analysis before each phase. Object oriented models incorporate iteration, parallelism and incremental development.
Agile testing is a software testing practice that follows the principles of agile software development. In agile testing, testing is continuous and occurs throughout the development process rather than as a separate phase. All team members, including developers and business analysts, are involved in testing. Feedback is provided frequently in short iterations to quickly adapt to changing requirements. This allows issues to be identified and addressed earlier compared to traditional waterfall development models.
The document introduces software process models including the waterfall model, evolutionary development, and component-based software engineering. It describes the Rational Unified Process model and discusses key process activities like requirements engineering, design, implementation, testing, and evolution. Computer-aided software engineering tools are introduced as a way to support various activities in the software development process.
The document compares various software development life cycle (SDLC) models, including the waterfall model, spiral model, prototype model, and iterative model. It discusses the advantages and limitations of each model. The waterfall model is simple and easy to understand but cannot accommodate changing requirements. The spiral model emphasizes risk analysis but can be costly. The prototype model involves user feedback early but risks wasted time if the prototype is rejected. The iterative model allows for changes between iterations but requires more management attention. In conclusion, the best model depends on the project's characteristics and needs.
The document discusses different software development life cycle (SDLC) models including the waterfall model, spiral model, and agile model. It provides an overview of each model's phases, advantages, and disadvantages. The waterfall model is the oldest and most widely used. It is linear but can lead to confusion if requirements are unclear. The spiral model is adapted for large, complicated projects and allows for changes and testing at each phase but requires an experienced team. The agile model prioritizes requirements, verification, design, and implementation through iterative development with customer involvement and fixed time periods.
This document discusses various software development life cycle (SDLC) models including waterfall, iterative waterfall, rapid prototype, evolutionary, spiral, fish, V-shape, RAD, and incremental models. For each model, it provides a brief description and highlights the advantages and disadvantages. The models differ in their structure, approach to requirements, testing, flexibility, and ability to handle risk and changing requirements.
Software Development Life Cycle Models | What are Software Process Models ?
Here you are going to know What is Software Development Life Cycle Model or What are Software Process Models?
Software Process Models defines a distinct set of activities, actions, tasks, milestones, and work products that are required to engineer high-quality software...
For more knowledge watch full video...
Video URL:
https://youtu.be/3Lxnn0O3xaM
YouTube Channel URL:
https://www.youtube.com/channel/UCKVvceV1RGXLz0GeesbQnVg
Google+ Page URL:
https://plus.google.com/113458574960966683976/videos?_ga=1.91477722.157526647.1466331425
My Website Link:
http://appsdisaster.blogspot.com/
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Thanks
Software Process Models | Software Development Process Models | SDLC | Traditional Software Process Models | Waterfall Model Incremental Model | Prototyping Model | Evolutionary Process Model
The document discusses the software development life cycle (SDLC) and its various phases and models. It describes the six main phases of the SDLC as requirements gathering and analysis, design, implementation/coding, testing, deployment, and maintenance. It then explains different SDLC models including waterfall, V-shaped, prototype, spiral, iterative incremental, big bang, and agile. The conclusion states that the best model depends on factors like requirements clarity, complexity, size, cost and skills. The waterfall model is basic but other models are variations that allow for flexibility.
Evolutionary Software Process Module in Easy Terminology by Taha ShahidTahaa Shahid
The main objective of this presentation was to focus and describe the Evolutionary Software Process Model in easy terminologies. ESPM is a model, used by Software companies for the completion of their products.
This document discusses different process models used in software development. It describes the key phases and characteristics of several common process models including waterfall, prototyping, V-model, incremental, iterative, spiral and agile development models. The waterfall model involves sequential phases from requirements to maintenance without iteration. Prototyping allows for user feedback earlier. The V-model adds verification and validation phases. Incremental and iterative models divide the work into smaller chunks to allow for iteration and user feedback throughout development.
The V-Model is a software development lifecycle model where development and testing occur in sequential and inverse phases resembling the shape of a V. It is called the V-Model because the process looks like the letter V, with validation on the left side and verification on the right. The key phases include requirements analysis, design, coding, unit testing, integration testing, system testing, and acceptance testing. The V-Model allows testing to start early and to be conducted at each phase, in parallel with development. It is simple to understand but works best for smaller, well-defined projects where requirements are stable.
The document provides information on various software versions used for engineering drawings, documents, technical illustrations, web browsing and document viewing. It lists applications such as AutoCAD, CorelDRAW, Microsoft Office, Netscape Navigator and Acrobat software. It also provides a link for an up-to-date list of software versions.
This document outlines the "V" model approach to system development. It discusses the key stages of the "V" model including requirements elicitation, system design, and testing phases. It provides an illustration of the "V" model workflow. The document also covers advantages of the "V" model like defined goals for each phase and early test planning. Disadvantages discussed are difficulty changing requirements late and limitations for complex projects. Finally, it provides examples comparing the suitability of the "V" and waterfall models for different problem scenarios.
The document discusses different software development life cycle (SDLC) models and phases. It describes the waterfall model, V-model, agile model, incremental model, and iterative model. The waterfall model consists of requirement analysis, system design, implementation, testing, and maintenance phases. The V-model includes verification and validation phases like requirement analysis, high-level design, detailed design, coding, unit testing, integration testing, system testing, and acceptance testing. Agile follows iterative development in short iterations. The incremental model develops the system in modules, while the iterative model refines requirements and functionality through iterations.
In Iterative model, iterative process starts with a simple implementation of a small set of the software requirements and iteratively enhances the evolving versions until the complete system is implemented and ready to be deployed.
This presentation is about a lecture I gave within the "Software systems and services" immigration course at the Gran Sasso Science Institute, L'Aquila (Italy): http://cs.gssi.infn.it/.
http://www.ivanomalavolta.com
In this session you will learn:
SDLC and Quality Standard
What is SDLC and Stages?
Phases of SDLC
Design Types
SDLC Models
Waterfall Model
Spiral Model
V-Model
Big Bang Model
The document discusses the V-model of the system development life cycle (SDLC). It begins by defining the SDLC as a structured process or framework for developing software. It then describes the key phases of the V-model - requirements analysis, design, implementation, unit testing, integration testing, system testing, and acceptance testing. Each phase in the development process (left side of the V) has a corresponding testing phase (right side of the V) to validate the work. The V-model aims to ensure quality at each stage and prevent defects from propagating through the lifecycle.
The document discusses several software development life cycle (SDLC) models:
- Waterfall model involves sequential phases of requirements, design, implementation, testing and deployment with defined deliverables for each phase. It works well for stable requirements but lacks flexibility.
- V-shaped model emphasizes verification and validation testing in parallel with development phases. It focuses on planning testing in early phases.
- Prototyping model involves building prototypes to clarify requirements with user feedback before final development.
- RAD model focuses on rapid delivery through time-boxed iterations with customer involvement.
- Incremental model prioritizes and implements requirements in groups to provide early functionality.
- Spiral model combines prototyping, risk analysis
The document describes the six main phases of the Software Development Life Cycle (SDLC): 1) Planning and Requirement Analysis, 2) Defining Requirements, 3) Designing the product architecture, 4) Building or Developing the Product, 5) Testing the Product, and 6) Deployment in the Market and Maintenance. Each phase is explained in 1-2 sentences with an emphasis on gathering requirements, designing the architecture, coding, testing, and deploying the final product.
Comparison of Software Engineering Modelstahir iqbal
This document provides an overview of several software development process models: waterfall model, iterative model, prototyping model, and spiral model. It describes the basic principles, advantages, and disadvantages of each model. The waterfall model involves sequential phases from requirements to maintenance. The iterative model divides a project into smaller parts with feedback between phases. The prototyping model emphasizes user involvement through prototypes. The spiral model combines elements of design and prototyping with a focus on risk assessment through multiple cycles.
The document outlines the software development life cycle (SDLC), which includes requirement analysis, design, implementation, testing, and maintenance phases. In the requirement analysis phase, functional, performance, and design requirements are gathered. The design phase involves creating flow charts, UML diagrams, and ensuring the software is compatible, user-friendly, and secure. Implementation consists of coding, documentation, and testing the software. Testing verifies the software through unit, system, static, dynamic, security, alpha, and beta tests. Maintenance includes bug fixing, upgrades, enhancements, and security updates.
The document discusses different software development models. It describes the waterfall model as the oldest and most linear sequential model, where each phase must be completed before moving to the next. The phases are requirements, design, coding/implementation, testing, and maintenance. While simple, it is not suitable for complex or long-term projects where requirements may change. The incremental model allows for more flexibility and ability to change requirements by developing the product incrementally in iterations until complete.
The document discusses the waterfall model, which is an early software development life cycle approach where each phase must be completed before the next begins, with no overlapping phases. The phases include requirements, design, implementation, testing, and maintenance. The waterfall model works best for smaller, clearly-defined projects with stable requirements and is simple to understand and use. However, it does not allow for changing requirements and produces no working software until late in the cycle.
An Approach To Software Development Life CycleBettyBaker
The document describes the waterfall software development life cycle (SDLC) approach and a modified implementation of it. The waterfall approach consists of five phases: requirements, design, coding, testing, and maintenance. The modified approach combines the requirements and design phases into a systems engineering phase. It also implements coding in mini code locks with testing after each lock rather than once at the end. Both aim to systematically structure the development process.
The document discusses software processes and provides an overview of key concepts:
1) It describes different software process models including waterfall, incremental development, and reuse-oriented processes.
2) It covers important process activities like requirements specification, design/implementation, validation, and evolution.
3) It discusses approaches for coping with changing requirements like prototyping and incremental delivery.
The Rational Unified Process (RUP) is presented as a modern generic software process that incorporates elements of other process models.
Software Development Life Cycle Models | What are Software Process Models ?
Here you are going to know What is Software Development Life Cycle Model or What are Software Process Models?
Software Process Models defines a distinct set of activities, actions, tasks, milestones, and work products that are required to engineer high-quality software...
For more knowledge watch full video...
Video URL:
https://youtu.be/3Lxnn0O3xaM
YouTube Channel URL:
https://www.youtube.com/channel/UCKVvceV1RGXLz0GeesbQnVg
Google+ Page URL:
https://plus.google.com/113458574960966683976/videos?_ga=1.91477722.157526647.1466331425
My Website Link:
http://appsdisaster.blogspot.com/
If you are interested in learning more about topics like this so Please don't forget to like, share, & Subscribe to this channel.
Thanks
Software Process Models | Software Development Process Models | SDLC | Traditional Software Process Models | Waterfall Model Incremental Model | Prototyping Model | Evolutionary Process Model
The document discusses the software development life cycle (SDLC) and its various phases and models. It describes the six main phases of the SDLC as requirements gathering and analysis, design, implementation/coding, testing, deployment, and maintenance. It then explains different SDLC models including waterfall, V-shaped, prototype, spiral, iterative incremental, big bang, and agile. The conclusion states that the best model depends on factors like requirements clarity, complexity, size, cost and skills. The waterfall model is basic but other models are variations that allow for flexibility.
Evolutionary Software Process Module in Easy Terminology by Taha ShahidTahaa Shahid
The main objective of this presentation was to focus and describe the Evolutionary Software Process Model in easy terminologies. ESPM is a model, used by Software companies for the completion of their products.
This document discusses different process models used in software development. It describes the key phases and characteristics of several common process models including waterfall, prototyping, V-model, incremental, iterative, spiral and agile development models. The waterfall model involves sequential phases from requirements to maintenance without iteration. Prototyping allows for user feedback earlier. The V-model adds verification and validation phases. Incremental and iterative models divide the work into smaller chunks to allow for iteration and user feedback throughout development.
The V-Model is a software development lifecycle model where development and testing occur in sequential and inverse phases resembling the shape of a V. It is called the V-Model because the process looks like the letter V, with validation on the left side and verification on the right. The key phases include requirements analysis, design, coding, unit testing, integration testing, system testing, and acceptance testing. The V-Model allows testing to start early and to be conducted at each phase, in parallel with development. It is simple to understand but works best for smaller, well-defined projects where requirements are stable.
The document provides information on various software versions used for engineering drawings, documents, technical illustrations, web browsing and document viewing. It lists applications such as AutoCAD, CorelDRAW, Microsoft Office, Netscape Navigator and Acrobat software. It also provides a link for an up-to-date list of software versions.
This document outlines the "V" model approach to system development. It discusses the key stages of the "V" model including requirements elicitation, system design, and testing phases. It provides an illustration of the "V" model workflow. The document also covers advantages of the "V" model like defined goals for each phase and early test planning. Disadvantages discussed are difficulty changing requirements late and limitations for complex projects. Finally, it provides examples comparing the suitability of the "V" and waterfall models for different problem scenarios.
The document discusses different software development life cycle (SDLC) models and phases. It describes the waterfall model, V-model, agile model, incremental model, and iterative model. The waterfall model consists of requirement analysis, system design, implementation, testing, and maintenance phases. The V-model includes verification and validation phases like requirement analysis, high-level design, detailed design, coding, unit testing, integration testing, system testing, and acceptance testing. Agile follows iterative development in short iterations. The incremental model develops the system in modules, while the iterative model refines requirements and functionality through iterations.
In Iterative model, iterative process starts with a simple implementation of a small set of the software requirements and iteratively enhances the evolving versions until the complete system is implemented and ready to be deployed.
This presentation is about a lecture I gave within the "Software systems and services" immigration course at the Gran Sasso Science Institute, L'Aquila (Italy): http://cs.gssi.infn.it/.
http://www.ivanomalavolta.com
In this session you will learn:
SDLC and Quality Standard
What is SDLC and Stages?
Phases of SDLC
Design Types
SDLC Models
Waterfall Model
Spiral Model
V-Model
Big Bang Model
The document discusses the V-model of the system development life cycle (SDLC). It begins by defining the SDLC as a structured process or framework for developing software. It then describes the key phases of the V-model - requirements analysis, design, implementation, unit testing, integration testing, system testing, and acceptance testing. Each phase in the development process (left side of the V) has a corresponding testing phase (right side of the V) to validate the work. The V-model aims to ensure quality at each stage and prevent defects from propagating through the lifecycle.
The document discusses several software development life cycle (SDLC) models:
- Waterfall model involves sequential phases of requirements, design, implementation, testing and deployment with defined deliverables for each phase. It works well for stable requirements but lacks flexibility.
- V-shaped model emphasizes verification and validation testing in parallel with development phases. It focuses on planning testing in early phases.
- Prototyping model involves building prototypes to clarify requirements with user feedback before final development.
- RAD model focuses on rapid delivery through time-boxed iterations with customer involvement.
- Incremental model prioritizes and implements requirements in groups to provide early functionality.
- Spiral model combines prototyping, risk analysis
The document describes the six main phases of the Software Development Life Cycle (SDLC): 1) Planning and Requirement Analysis, 2) Defining Requirements, 3) Designing the product architecture, 4) Building or Developing the Product, 5) Testing the Product, and 6) Deployment in the Market and Maintenance. Each phase is explained in 1-2 sentences with an emphasis on gathering requirements, designing the architecture, coding, testing, and deploying the final product.
Comparison of Software Engineering Modelstahir iqbal
This document provides an overview of several software development process models: waterfall model, iterative model, prototyping model, and spiral model. It describes the basic principles, advantages, and disadvantages of each model. The waterfall model involves sequential phases from requirements to maintenance. The iterative model divides a project into smaller parts with feedback between phases. The prototyping model emphasizes user involvement through prototypes. The spiral model combines elements of design and prototyping with a focus on risk assessment through multiple cycles.
The document outlines the software development life cycle (SDLC), which includes requirement analysis, design, implementation, testing, and maintenance phases. In the requirement analysis phase, functional, performance, and design requirements are gathered. The design phase involves creating flow charts, UML diagrams, and ensuring the software is compatible, user-friendly, and secure. Implementation consists of coding, documentation, and testing the software. Testing verifies the software through unit, system, static, dynamic, security, alpha, and beta tests. Maintenance includes bug fixing, upgrades, enhancements, and security updates.
The document discusses different software development models. It describes the waterfall model as the oldest and most linear sequential model, where each phase must be completed before moving to the next. The phases are requirements, design, coding/implementation, testing, and maintenance. While simple, it is not suitable for complex or long-term projects where requirements may change. The incremental model allows for more flexibility and ability to change requirements by developing the product incrementally in iterations until complete.
The document discusses the waterfall model, which is an early software development life cycle approach where each phase must be completed before the next begins, with no overlapping phases. The phases include requirements, design, implementation, testing, and maintenance. The waterfall model works best for smaller, clearly-defined projects with stable requirements and is simple to understand and use. However, it does not allow for changing requirements and produces no working software until late in the cycle.
An Approach To Software Development Life CycleBettyBaker
The document describes the waterfall software development life cycle (SDLC) approach and a modified implementation of it. The waterfall approach consists of five phases: requirements, design, coding, testing, and maintenance. The modified approach combines the requirements and design phases into a systems engineering phase. It also implements coding in mini code locks with testing after each lock rather than once at the end. Both aim to systematically structure the development process.
The document discusses software processes and provides an overview of key concepts:
1) It describes different software process models including waterfall, incremental development, and reuse-oriented processes.
2) It covers important process activities like requirements specification, design/implementation, validation, and evolution.
3) It discusses approaches for coping with changing requirements like prototyping and incremental delivery.
The Rational Unified Process (RUP) is presented as a modern generic software process that incorporates elements of other process models.
The document describes different software development processes and models. It discusses the waterfall model, incremental development, reuse-oriented development, and the spiral model. The waterfall model involves sequential phases from requirements to maintenance. Incremental development interleaves specification, development and validation. Reuse focuses on assembling systems from existing components. The spiral model is iterative with risk assessment at each loop. The Rational Unified Process combines elements of these models into phases of inception, elaboration, construction and transition.
This document discusses software processes and models. It covers the following key points:
1. Software processes involve activities like specification, design, implementation, validation and evolution to develop software systems. Common process models include waterfall, incremental development and reuse-oriented development.
2. Processes need to cope with inevitable changes. This can involve prototyping to avoid rework or using incremental development and delivery to more easily accommodate changes.
3. The Rational Unified Process is a modern process model with phases for inception, elaboration, construction and transition. It advocates iterative development and managing requirements and quality.
This document discusses different software processes and activities. It covers incremental development, which delivers software in increments and allows for early customer feedback. Reuse-oriented engineering focuses on integrating existing components. Key process activities include specification, design/implementation, validation, and evolution. Specification involves requirements analysis. Design translates requirements into a structure, while implementation creates an executable program. Validation verifies the system meets requirements through testing. Evolution allows software to change with changing needs.
This document discusses three software process models: the waterfall model, incremental development, and reuse-oriented software engineering. The waterfall model represents the software development process as sequential phases such as requirements, design, implementation, testing, and maintenance. Incremental development interleaves these phases and develops the system in a series of versions that add new functionality. Reuse-oriented engineering focuses on integrating existing reusable components rather than developing everything from scratch.
Miss Aster Noor introduces the concepts of software processes and process models. The chapter covers software process models like waterfall, incremental development, and integration/configuration. It discusses the core process activities of requirements engineering, development, testing, and evolution. The chapter aims to explain why processes must adapt to changes and how process improvement affects quality.
The document discusses software processes and process models. It covers key topics like the waterfall model, incremental development, and reuse-oriented processes. The main activities involved in any software process are specification, design and implementation, validation, and evolution. Specification defines what the system should do, design implements the system structure, validation checks it meets requirements, and evolution handles changing needs. Process models organize these activities differently, like sequentially in waterfall or interleaved in incremental development.
This document provides an overview of software processes and models. It discusses topics like specification, design, implementation, validation, evolution, and process improvement. Common process models like waterfall, incremental development, and integration/configuration are described. The document also covers process activities, coping with change through techniques like prototyping and incremental delivery, and process improvement through models like the spiral model.
This document discusses software processes and process models. It covers topics such as the waterfall model, incremental development, integration and configuration, process activities including specification, design, implementation, validation and evolution. It also discusses coping with change through techniques like prototyping and incremental delivery. The key aspects of software process models, activities, and improvement are summarized.
this is for software engineering and design used to make attention of what you gonnal do in your next session i hope you to enjoy by reading this lecture
The document discusses software processes and activities. It describes common process models like waterfall, incremental development, and configuration management. The key activities involved in most processes are specification, development, validation, and evolution. Specification defines system requirements while development includes design, implementation, and debugging. Validation ensures the system meets requirements through testing. Processes also evolve to adapt to changing needs.
This document discusses software processes and activities. It covers topics like software process models, process activities, and process improvement. Some key points include: a software process involves specification, design, implementation, validation and evolution; process models include waterfall, incremental development, and configuration/integration; activities involve specification, design/implementation, validation and evolution; and testing is a major validation activity involving component, system and customer testing.
The document provides an overview of software processes and models. It discusses the waterfall model, incremental development, and reuse-oriented processes. The waterfall model involves separate sequential phases while incremental development interleaves specification, development and validation. The Rational Unified Process (RUP) combines elements of different models and involves iterative phases of inception, elaboration, construction and transition. RUP aims to reduce risks and accommodate changes through incremental delivery and development.
The document summarizes key aspects of software processes as discussed in Chapter 2, including common process models like waterfall, incremental development, and reuse-oriented processes. It also describes common process activities like specification, design/implementation, validation, and evolution. A detailed explanation is provided of the Rational Unified Process (RUP), which incorporates elements of other models and defines phases like inception, elaboration, construction, and transition that may be iterated.
The document summarizes key aspects of software processes as discussed in Chapter 2, including common process models like waterfall, incremental development, and reuse-oriented processes. It also describes common process activities like specification, design/implementation, validation, and evolution. A detailed explanation is provided of the Rational Unified Process (RUP), which incorporates elements of other models and defines phases like inception, elaboration, construction, and transition that may be iterated.
The document discusses the software development life cycle (SDLC). It describes the typical phases of SDLC including problem definition, program design, coding, debugging, testing, documentation, maintenance, and extension/redesign. It also covers different SDLC models like waterfall, prototyping, and agile development. The SDLC process is best for structured environments while iterative models work better for web and e-commerce projects where frequent stakeholder feedback is needed.
SDLC stands for Software Development Life Cycle also known as Application Development Life Cycle. This terms mostly used in Software Engineering. Using this life cycle process can make planning, designing, coding, testing & maintains for the software.
The document describes different software development process models including the waterfall model, prototyping model, incremental development, spiral development, agile methods, and extreme programming. It explains each model and compares their advantages and disadvantages. The waterfall model is most appropriate when requirements are stable while agile methods are best for changing requirements but can be difficult to manage.
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তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
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ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
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Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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1. Chapter 2
Software Life Cycle
CONTENTS
2.1 INTRODUCTION ...........................................................................................................................................3
2.2 PROCESS DESCRIPTION ............................................................................................................................3
2.2.1 LIFE CYCLE MODELS ..................................................................................................................................4
2.2.1.1 Waterfall Model .....................................................................................................................................4
2.2.1.2 Incremental Model.................................................................................................................................5
2.2.1.3 Evolutionary Model (Prototyping).........................................................................................................6
2.2.1.4 Spiral Model ..........................................................................................................................................7
2.3 APPLICATION ...............................................................................................................................................9
2.3.1 EVOLUTIONARY ACQUISITION AND SPIRAL DEVELOPMENT .......................................................................9
2.3.2 SELECTION MATRIX .................................................................................................................................10
2.4 LIFE CYCLE CHECKLIST ........................................................................................................................11
2.4.1 BEGINNING A DEVELOPMENT PROJECT ....................................................................................................11
2.4.2 DEVELOPMENT PROJECT IS UNDER WAY .................................................................................................12
2.5 REGULATIONS............................................................................................................................................12
2.6 REFERENCES ..............................................................................................................................................12
2.7 RESOURCES.................................................................................................................................................12
2.7.1 SOFTWARE LIFE CYCLE ............................................................................................................................12
2.7.2 SOFTWARE ACQUISITION/DEVELOPMENT.................................................................................................13
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2. Chapter 2: Software Life Cycle Condensed GSAM Handbook
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3. Chapter 2
Software Life Cycle
2.1 Introduction
In the early days of computing, software was developed by many individuals following their own methods. Often,
the methods employed some form of “code and fix”, where the programmer writes some code and then tests it to see
how it performs. The programmer then uses the test results to modify or fix the code and tests again. Programmers
were able to get by with this type of development for two reasons. First, no better way had been developed, and sec-
ond, software was not that complex. As software grew more complicated and organizations relied on computers for
more of their operations, including finances and even human lives, this laissez faire approach to programming gave
way to more disciplined methods. The overall framework in which software is conceived, developed, and main-
tained is known as the Software Development Life Cycle (SDLC). This chapter discusses the various types of
SDLCs, along with their advantages and disadvantages.
A life cycle model defines the phases, milestones, deliverables, and evaluation criteria of the software devel-
opment process. These form the basis of the work breakdown structure (WBS), used for project planning and man-
agement.
2.2 Process Description
Life cycles are usually referred to as models, and define the phases of a software development effort. Simple life
cycles may have only three phases, Design, Development, and Maintenance; while complex life cycles may include
20 or more phases. Generally, software life cycles include the phases shown in Figure 2-1.
Requirements
Design
Implementation
Testing
Deployment
Maintenance
Figure 2-1 Common Life Cycle Phases
These “classic” phases are often divided into additional phases to allow better definition and control of the develop-
ment process. They may also be repeated in an iterative manner, depending on the software complexity and the life
cycle model used. Most life cycle phases are identical or similar to the common phases identified above and the
following general descriptions will apply across most models. Note that single phases are composed of multiple ac-
tivities.
The Requirements Phase consists of analyzing the problem or need for which the software is being developed. This
analysis, a systems engineering activity, develops and specifies requirements, stating what the software must do. In
addition to stated requirements, requirements are derived from higher-level requirements and statements of need.
In the Design Phase the software structure is defined. Technical approaches are chosen and problems are solved
conceptually. This phase is often divided into a Preliminary Design Phase and a Detailed Design Phase. In the pre-
liminary design the initial software architecture is developed. In the detailed design, functional modules are defined,
along with user interfaces and interfaces between modules.
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4. Chapter 2: Software Life Cycle Condensed GSAM Handbook
The Implementation Phase (sometimes called the Development Phase) is where the programming or coding takes
place to execute the software design. This phase is often iterative, with unit and integration testing being performed
after a software build, and the results used in another round of programming.
Software is tested for functionality and requirements compliance during the Testing Phase. Testing is often split into
three separate phases: Unit Testing, Integration Testing, and Acceptance Testing. The first two may be part of a re-
peated cycle of coding and testing, while acceptance testing verifies requirements compliance.
During the Deployment Phase the software is installed in the intended system and users are trained in its operation.
At this point the software development effort is considered complete.
The Maintenance Phase includes fixing errors and modifying or upgrading the software to provide additional func-
tionality, such as enabling the software to work with new computing platforms. This phase costs far more in time
and effort than the original development. Software maintainers must relearn the original software code to understand
what was done, then make changes to specific modules to produce the desired effect without interfering with rest of
the software. It’s much easier to change requirements earlier than it is to change software code later. This also means
that software should be developed with maintenance in mind.
2.2.1 Life cycle Models
There are many life cycle models, or paradigms. Most of them are variations of three classic software development
models: the waterfall, incremental, and spiral models. These three, along with the evolutionary model, are summa-
rized here.
2.2.1.1 Waterfall Model
The waterfall model, also known as the linear sequential model, is shown in Figure 2-2 with its major phases, mile-
stones, and products. It is a highly structured development process, first used on DoD software projects in the 1970s.
It is the “traditional” approach to software development and was derived from defense and aerospace project lifecy-
cles. It is considered superior to the previously used “code and fix” methods of software development, which lacked
formal analysis and design.
System Requirements System Segment
Definition Specification
Software Requirements Software Requirements
Analysis Specification
System
Functional
Review Software Design
Preliminary Design
Document - Preliminary
Software
Specification
Review Software Design
Detailed Design
Document - Final
Preliminary
Design Review
Coding and Unit Software Units
Testing (SUs)
Critical Design
Review
Component Integration
and Testing
Integration Testing Software Items (SIs)
Test
Readiness
Review System Testing Tested Software
Maintain Software
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5. Condensed GSAM Handbook Chapter 2: Software Life Cycle
Figure 2-2 Waterfall Model [1]
The waterfall model is documentation-intensive, with earlier phases documenting what must be done and subsequent
phases adding greater detail and defining how it should be done. The output from one phase serves as the input to
the next phase, with the project flowing from one step to the next in a waterfall fashion. Phases are assumed to be
sequential, with only localized feedback during the transition between phases. This is accomplished by using re-
views as gates. Comprehensive reviews validate the work of one phase, and require the resolution of any problems
before development is allowed to proceed to the next phase.
An important consideration for the Waterfall model is that fixes or modifications are often put off until the mainte-
nance phase. This can be very costly, as the cost to correct a problem gets higher with each successive phase.
Advantages
• System is well documented.
• Phases correspond with project management phases.
• Cost and schedule estimates may be lower and more accurate.
• Details can be addressed with more engineering effort if software is large or complex.
Disadvantages
• All risks must be dealt with in a single software development effort.
• Because the model is sequential, there is only local feedback at the transition between phases.
• A working product is not available until late in the project.
• Progress and success are not observable until the later stages. If a mistake or deficiency exists in the documen-
tation of earlier phases, it may not be discovered until the product is delivered.
• Corrections must often wait for the maintenance phase.
Application
The Waterfall model can be successfully used when requirements are well understood in the beginning and are not
expected to change or evolve over the life of the project. Project risks should be relatively low.
2.2.1.2 Incremental Model
The incremental model is essentially a series of waterfall cycles. One variant is shown in Figure 2-3. The require-
ments are known at the beginning of the project and are divided into groups for incremental development. A core set
of functions is identified in the first cycle and is built and deployed as the first release. The software development
cycle is repeated, with each release adding more functionality until all requirements are met. Each development cy-
cle acts as the maintenance phase for the previous software release. While new requirements that are discovered
during the development of a given cycle can be implemented in subsequent cycles, this model assumes that most
requirements are known up front. The effort is planned and executed to satisfy the initial list of requirements. A
modification to the incremental model allows development cycles to overlap. That is, a subsequent cycle may begin
before the previous cycle is complete.
Figure 2-3 The Incremental Model is a Series of Waterfalls
Advantages
• Provides some feedback, allowing later development cycles to learn from previous cycles.
• Requirements are relatively stable and may be better understood with each increment.
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6. Chapter 2: Software Life Cycle Condensed GSAM Handbook
• Allows some requirements modification and may allow the addition of new requirements.
• It is more responsive to user needs than the waterfall model.
• A usable product is available with the first release, and each cycle results in greater functionality.
• The project can be stopped any time after the first cycle and leave a working product.
• Risk is spread out over multiple cycles.
• This method can usually be performed with fewer people than the waterfall model.
• Return on investment is visible earlier in the project. [7]
• Project management may be easier for smaller, incremental projects. [7]
• Testing may be easier on smaller portions of the system.
Disadvantages
• The majority of requirements must be known in the beginning.
• Formal reviews may be more difficult to implement on incremental releases than on a complete system. [2]
• Because development is spread out over multiple iterations, interfaces between modules must be well-defined in
the beginning. [2]
• Cost and schedule overruns may result in an unfinished system.
• Operations are impacted as each new release is deployed.
• Users are required to learn how to use a new system with each deployment.
Application
The incremental model is good for projects where requirements are known at the beginning, but which need func-
tionality early in the project or which can benefit from the feedback of earlier cycles. Because each cycle produces a
working system, it may also be advantageous for projects whose continued funding is not assured and may be cut at
any time. It is best used on low to medium-risk programs. If the risks are too high to build a successful system using
a single waterfall cycle, spreading the development out over multiple cycles may lower the risks to a more manage-
able level. [3]
2.2.1.3 Evolutionary Model (Prototyping)
The evolutionary model, like the incremental model, develops a product in multiple cycles. Unlike the incremental
model, which simply adds more functionality with each cycle, this model produces a more refined prototype system
with each iteration. The process, shown in Figure 2-4, begins in the center with initial requirements and plans, and
progresses through multiple cycles of planning, risk analysis, engineering, and customer evaluation. Each cycle pro-
duces a prototype that the customer evaluates, followed by a refinement of requirements.
Specification, development, and testing activi-
ties are carried out concurrently (in the engi- Planning Risk Analysis
neering quadrant) with rapid feedback. Since
Initial Based on Initial
requirements continue to change, documenta- Requirements
Requirements &
tion is minimal, although essential information Planning Based on
must still be included for understanding the Customer Reaction
system and for future support. Implementation
compromises are often made in order to get the Initial Prototype
prototype working – permanent fixes can be Next Prototype
made with the next prototype. Operational ca-
Engineered System
pability is achieved early, but users must be Customer
willing to learn how to use each new prototype. Evaluation Engineering
General system requirements must be known
prior to development. This is particularly help- Figure 2-4 First Generation Evolutionary Model [4]
ful where evolving technology is being intro-
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7. Condensed GSAM Handbook Chapter 2: Software Life Cycle
duced into the project. The evolutionary model relies heavily on user feedback after each implementation to refine
requirements for the next evolutionary step.
Advantages [5]
• Project can begin without fully defining or understanding requirements.
• Final requirements are improved and more in line with real user needs.
• Risks are spread over multiple software builds and controlled better.
• Operational capability is achieved earlier in the program.
• Newer technology can be incorporated into the system as it becomes available during later prototypes.
• Documentation emphasizes the final product instead of the evolution of the product. [2]
• This method combines a formal specification with an operational prototype. [2]
Disadvantages [5]
• Because there are more activities and changes, there is usually an increase in both cost and schedule over the
waterfall method.
• Management activities are increased.
• Instead of a single switch over to a new system, there is an ongoing impact to current operations.
• Configuration management activities are increased.
• Greater coordination of resources is required.
• Users sometimes mistake a prototype for the final system.
• Prototypes change between cycles, adding a learning curve for developers and users.
• Risks may be increased in the following areas:
− Requirements – Temptation to defer requirements definition.
− Management – Programs are more difficult to control. Better government/contractor cooperation needed.
− Approval – Vulnerable to delays in funding approval, which can increase schedule and costs.
− Architectural – Initial architecture must accommodate later changes.
− Short term benefits – Risk of becoming driven by operational needs rather than program goals.
− Risk avoidance – Tendency to defer riskier features until later.
− Exploitation by suppliers – Government bargaining power may be reduced because initial contract may not
complete the entire task, and subsequent contracts are not likely to be competed.
− Patchwork quilt effects – If changes are poorly controlled, the product quality can be compromised.
Application
The evolutionary model can be employed on most types of acquisitions. However, it is usually employed on medium
to high-risk systems. The evolutionary model should be considered for systems where requirements are not all
known or not yet refined, but are expected to evolve. It is more applicable to new systems than upgrading existing
software. [2] The developing and using organizations must be flexible and willing to work with evolving prototypes.
Programs well suited to employ the evolutionary model have some or all of the following characteristics. [5]
• Software intensive systems. • Have a large number of diverse users.
• Have rapidly changing software technology. • Developing an unprecedented system.
• Humans are an integral part of the system. • Limited capability is needed quickly.
2.2.1.4 Spiral Model
The spiral model [6] was developed with the goal of reducing risk in the software life cycle. It combines elements
of the waterfall, evolutionary, and incremental models, and depending on how it is implemented can strongly resem-
ble any combination of the others. The model’s spiral nature can be seen in Figure 2-5, one of several variants. The
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8. Chapter 2: Software Life Cycle Condensed GSAM Handbook
project starts at the center and progresses through multiple cycles, each working through the software development
activities associated with the four quadrants:
1. Determine objectives, alternatives, constraints.
2. Evaluate alternatives. Identify and resolve risks.
3. Develop the next-level product.
4. Plan the next phase.
Risk management is a key element of the Spiral model and each round of the spiral identifies problems with the
highest risk and develops solutions for that set of problems. The process may even resemble a waterfall with addi-
tional risk management techniques. Each cycle ends in a review in which stakeholders agree on plans for the next
cycle. While a prototype may be produced for IOC, software is usually not developed for release until the last cycle.
[7]
DETERMINE OBJECTIVES, EVALUATE ALTERNATIVES,
ALTERNATIVES, AND IDENTIFY AND RESOLVE RISKS
CONTRAINTS Risk
Analysis
Support
and
Maintenance Risk
Objectives, Analysis
Alternatives, Updated
and Implementation Operational
Constraints Objectives, Risk Operational Prototyping
Alternatives, Design Analysis Prototyping
and Objectives,
Constraints Alternatives, System/ Risk Design
and Product Analysis Assessment
Constraints Objectives, Prototyping
Alternatives, Risk Demonstration
and Analysis Prototyping
Constraints Project Conceptual
Product Design Rqmts System Definition Prototyping
Review Review Review Review Concept of Simulations, Models,
Engineering and Operation Software and Benchmarks
Design Project System Require-
CSCI and Planning Software ments Spec, Detailed Updated
Integration Development Spec. Updated Design Detailed
Enhanced and Transition System Software Design
Operational Test Planning Software Architecture Code
Capability Site Specification and Code
Integration, Activation Preliminary Unit
Activation Training SDDs Test
and Planning Unit
Training Test
Planning Integration
and Test
Integration
IOC Qualification and Test
DELIVERY Testing
Formal
User Testing
FOC Acceptance
DELIVERY Test and
Training
FCA/PCA
PLAN NEXT PHASE DEVELOP NEXT LEVEL PRODUCT
Figure 2-5 The Spiral Model [5]
The Spiral model has been used extensively in the commercial world because of its performance in a market-driven
environment. It significantly reduces technical risk and more easily incorporates new technology and innovations.
At the same time, it tends to increase cost and schedule risks. In the past the Spiral model has been difficult to im-
plement in the DoD environment. This is because contracts with predefined deliverables and schedules do not easily
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9. Condensed GSAM Handbook Chapter 2: Software Life Cycle
accommodate repeating phases, requirement tradeoffs, and changing deliverables. [5] However, use of the Spiral
model, where applicable, is directed by DoDI 5000.2, and it has become somewhat popular in the Defense and
Aerospace industries.
Advantages
• It provides better risk management than other models.
• Requirements are better defined.
• System is more responsive to user needs.
Disadvantages
• The spiral model is more complex and harder to manage.
• This method usually increases development costs and schedule.
Application
The spiral method should be considered for projects where risks are high, requirements must be refined, and user
needs are very important.
2.3 Application
2.3.1 Evolutionary Acquisition and Spiral Development [8]
The Evolutionary Acquisition and Spiral Development approach to acquisition and development has been used to
satisfy the preference for evolutionary acquisition strategies established in DoD Directive 5000.1 and DoD Instruc-
tion 5000.2. This approach combines incremental, evolutionary, and spiral methods to reduce cycle time and speed
delivery of advanced capability to warfighters. It can develop or acquire both hardware and software in manageable
pieces and allow the insertion of new technology and capabilities over time.
Evolutionary acquisition fields an initial hardware or software increment (or block) of capability, providing im-
proved capability in a shorter period of time than is possible with a full development effort. This initial deployment
is followed by subsequent increments of capability delivered by multiple development cycles. Two variations of this
approach are possible. In one, the ultimate capability may be known at the beginning of the program. In the other,
the final capability evolves and is defined by matching maturing technologies to the evolving needs of the users.
Spiral development is the iterative process used for developing a defined set of capabilities in a single increment. An
increment is a militarily useful and supportable operational capability that can be developed, produced or acquired,
deployed, and sustained. An increment may include more than one spiral. Each increment has its own objectives set
by the user. An extension of this method can also be applied to Pre-planned Product Improvement (P3I) strategy
which adds improved capability to a mature system. This approach is shown in Figure 2-6.
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10. Chapter 2: Software Life Cycle Condensed GSAM Handbook
Evolutionary
Acquisition
Increment 1
Spirals Increment 2
Spirals Increment 3
P3I
Spirals Increment 4
Spirals
Figure 2-6 Evolutionary Acquisition, Spiral Development, and P3I
2.3.2 Selection Matrix
The purpose of Table 2-1 is to aid in the selection of a life cycle model. It lists various project constraints, along
with their applicability to models discussed in this chapter. The applicability is listed for the standard definitions of
the models and may not apply equally to modified models. [7] [9]
Table 2-1 Life Cycle Selection Matrix
Legend
Symbol Meaning
! Method is recommended for this constraint
" Method is satisfactory for this constraint.
(none) Method is not recommended for this constraint.
Waterfall Incremental Evolutionary Spiral
1. Requirements are known and stable. ! !
2. User needs are unclear/not well defined ! "
3. An early initial operational capability is ! !
needed.
4. Early functionality is needed to refine re- ! !
quirements for subsequent deliveries.
5. Significant risks need to be addressed. " ! !
6. Must interface with other systems. " " "
7. Need to integrate new or future technology. ! !
8. Software is large or complex ! ! " "
9. Software is small or limited in functionality. " " "
10. Software is highly interactive with user. " " "
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11. Condensed GSAM Handbook Chapter 2: Software Life Cycle
Waterfall Incremental Evolutionary Spiral
11. Software involves client/server function. " " " !
12. Initial cost and schedule estimates must be ! ! "
followed.
13. Detailed documentation necessary. ! ! "
14. Minimize impact on current operations. ! "
15. Full system must be implemented. ! " "
16. Reduce the number of people required. ! !
17. Project management must be simpler. ! "
18. System must be responsive to user needs. " ! !
19. Progress must be demonstrated early. ! !
20. User feedback is needed. ! ! "
21. Reduce the costs of fixes and corrections. " ! "
2.4 Life Cycle Checklist
This checklist is provided to assist you in choosing an appropriate life cycle for your project if you are beginning a
development effort, or to ensure you understand your development life cycle if your project is already under way. If
you cannot check an item off as affirmative, you need to rectify the situation yourself or get help in that area. [8]
2.4.1 Beginning a Development Project
! Do you have an understanding of common life cycle models, along with their strengths, weaknesses, and con-
straints?
! Has the operational concept been analyzed to determine what life cycle method would best support the acquisi-
tion?
! Can the requirements be fully defined prior to the beginning of the project? Are they stable?
! Do you know the timeline for deployment of the new system?
! Are funds secure for development of the entire system?
! Are the risks identified?
! Will risks impact the ability of the project to move forward at crucial points in the system development?
! Is new or developing technology to be used in the system?
! Will there be a parallel hardware development effort?
! Do you understand the level of complexity of the system to be developed?
! Do you know what the interfaces to existing and future systems are?
! Do you know the size and magnitude of the development effort?
! Do you understand the users’ needs?
! Are users able or expected to participate in the development?
! Do you know what types of acquisition contracts are available for this effort?
! When choosing a life cycle model, do you know why you are choosing it over other models?
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12. Chapter 2: Software Life Cycle Condensed GSAM Handbook
2.4.2 Development Project is Under Way
! Do you know what life cycle model was selected for your project?
! Do you understand the project aspects pertaining to the life cycle:
! Phases – What are they and what are they supposed to accomplish?
! Milestones – What are they? What is their significance?
! Criteria for transitioning from one phase to another?
! Deliverables – What is expected, during phases, and at the end of the project?
! Reviews – What is reviewed when? Who are the reviewers? What actions follow a successful review, an
unsuccessful review? What are the entry and exit criteria for each review?
! Feedback mechanisms – How is feedback obtained? Who provides it? Who receives it? How is it used?
! Documentation – What is to be produced and what it is used for?
! Do you know where your project is in the life cycle?
! Is your project following the life cycle?
2.5 Regulations
− Clinger-Cohen Act of 1996, The National Defense Authorization Act for Fiscal Year 1996.
− DoD 5000.2-R, Mandatory Procedures for Major Defense Acquisition Programs and Major Automated
Information System Acquisition Programs, June 2001.
− FAR -- Part 39; Acquisition of Information Technology; (FAC 97-27); 25 June 2001.
2.6 References
[1] Brundick, Bill, Editor, Parametric Cost Estimating Handbook, Chapter 5, Naval Sea Systems Command, Fall
1995.
[2] Sorensen, Reed, “A Comparison of Software Development Methodologies,” Crosstalk, January 1995
[3] Whitgift, David, Methods and Tools for Software Configuration Management, 1991, p17.
[4] Pressman, Roger S., “Understanding Software Engineering Practices, Required at SEI Level 2 Process Matur-
ity,” Software Engineering Training Series, Software Engineering Process Group, 30 July 1993.
[5] Guidelines for the Successful Acquisition and Management of Software Intensive Systems (GSAM), Version 3,
Chapter 5, USAF Software Technology Support Center, May 2000.
[6] Boehm, Barry W., “A Spiral Model of Software Development and Enhancement,” IEEE Computer, May 1988.
[7] McKenzie, Charlotte A., MIS327 - Systems Analysis and Design, Course Schedule, 1999.
[8] Memorandum from the Undersecretary of Defense for Acquisition Technology and Logistics, Subject: Evolu-
tionary Acquisition and Spiral Development, 12 April 2002.
[9] Quann, Eileen, personal communication to Lloyd K. Mosemann, II, September 1995.
2.7 Resources
2.7.1 Software Life Cycle
Association for Computing Machinery (ACM), ISO 12207 and Related Software Life-Cycle Standards:
www.acm.org/tsc/lifecycle.html
Crosstalk magazine articles:
− “Comparison of Software Development Methodologies”
www.stsc.hill.af.mil/crosstalk/1995/jan/comparis.asp
2-12 Februay 2003
13. Condensed GSAM Handbook Chapter 2: Software Life Cycle
− “Spiral Model as a Tool for Evolutionary Acquisition” www.stsc.hill.af.mil/crosstalk/2001/may/boehm.asp
− “Prototypes: Tools That Can Be Used and Misused” www.stsc.hill.af.mil/crosstalk/1994/jan/xt94d01g.asp
− “Extreme Methodologies for an Extreme World” www.stsc.hill.af.mil/crosstalk/2001/jun/leishman.asp
− “Dispelling the Process Myth: Having a Process Does Not Mean Sacrificing Agility or Creativity”
www.stsc.hill.af.mil/crosstalk/2001/nov/glazer.asp
− “Balancing Discipline and Flexibility With the Spiral Model and MBASE”
www.stsc.hill.af.mil/crosstalk/2001/dec/boehm.asp
− “Customizing the Software Process to Support Avionics Systems Enhancements”
www.stsc.hill.af.mil/crosstalk/2001/sep/donzelli.asp
− “Tailoring a Software Process for Software Project Plans Part 1: Context and Making Tailoring Decisions”
www.stsc.hill.af.mil/crosstalk/1996/apr/tailorin.asp
− “Tailoring a Software Process for Software Project Plans Part 2: Documenting the Project's Defined Soft-
ware Process” www.stsc.hill.af.mil/crosstalk/1996/may/tailorin.asp
− “MIL-STD-498: What's New and Some Real Lessons Learned”
www.stsc.hill.af.mil/crosstalk/1996/mar/lesslear.asp
DeGrace, Peter and Stahl, Leslie, Wicked Problems, Righteous Solutions: A Catalogue of Modern Software engi-
neering Paradigms, Yourdon Press.
Department of Energy (DOE) Software Engineering Methodology, Chapter 2: http://cio.doe.gov/sqse/sem_toc.htm
Department of Justice Systems Development Life Cycle Guidance Document:
www.usdoj.gov/jmd/irm/lifecycle/table.htm
Georgia Tech slides of software life cycles:
www.cc.gatech.edu/computing/SW_Eng/people/Faculty/Colin.Potts/Courses/3302/1-08-mgt/
Guidelines for the Successful Acquisition and Management of Software-Intensive Systems (GSAM), Version 3.0,
Chapter 5, OO-ALC/TISE, May 2000. Available for download at: www.stsc.hill.af.mil/gsam/guid.asp
LevelA Software, Introduction to life cycle models: www.levela.com/software_life_cycles_swdoc.htm
McKenzie, Charlotte A., MIS327 - Systems Analysis and Design, Course Schedule, 1999. See lecture with model
selection guide: http://metr.cua.edu/faculty/mckenzie/mis327/MIS%20327%20Course%20Schedule.html
OSD Program Manager’s Guide for Managing Software, Chapter 4 – Life Cycle Models:
http://www.geia.org/sstc/G47/SWMgmtGuide%20Rev%200.4.doc
Parametric Estimating Handbook, Chapter 6, International Society of Parametric Analysts (ISPA) – Commercial
Software Models: www.ispa-cost.org/PEIWeb/ch6.htm
Parametric Cost Estimating Handbook, Chapter 5, DoD, NASA, etc.:
www.jsc.nasa.gov/bu2/PCEHHTML/pceh.htm
Vision 7, overview of life cycle phases:
http://www.vision7.com/SoftwareDevelopment/ProjectLifeCycle/default.asp
2.7.2 Software Acquisition/Development
Air Force Acquisition Gameboard. Must have a .mil web presence: https://afkm.wpafb.af.mil/ASPs/Gameboard
Air Force Publication Web Site – The official source site for Air Force Administration Publications and Forms:
http://afpubs.hq.af.mil
Air Force Software Technology Support Center (STSC) documentation and standards:
http://stsc.hill.af.mil/doc/index.asp
Best Manufacturing Practices (BMP), TRIMS Risk Management and Best Practices software downloads:
www.bmpcoe.org/pmws/index.html Download KnowHow software and copies of DOD 5000.1, 5000.2, etc:
www.bmpcoe.org/pmws/download/knowhow.html
Crosstalk magazine. Extensive database of articles on software engineering. Published by the Air force Software
Technology Support Center (STSC): http://www.stsc.hill.af.mil/crosstalk/
Februay 2003 2-13
14. Chapter 2: Software Life Cycle Condensed GSAM Handbook
Defense Acquisition Deskbook. www.deskbook.osd.mil
Defense Acquisition University web site: www.dau.mil
Department of Defense single stock point of military specifications, standards, and related publications:
http://dodssp.daps.mil/
DoD Software Information Clearinghouse: www.dacs.dtic.mil
OSD acquisition web site: www.acq.osd.mil
RSPA. R. S. Pressman & Associates library of software engineering knowledge. In particular, see “An Adaptable
Process Model”: http://www.rspa.com/spi
Software Program Managers Network (SPMN). Sponsored by the Deputy Under Secretary of Defense for Science
and Technology (DUSD (S&T), Software Intensive Systems Directorate. www.spmn.com
SPMN Guidebooks available for download at: www.spmn.com/products_guidebooks.html
University of Southern California (USC) Center for Software Engineering (CSE), Technical Reports:
http://sunset.usc.edu/publications/TECHRPTS/index.html
2-14 Februay 2003