SDLC
- 1. Quality Assurance / Software Testing Training SDLC
- 2. Page 2Classification: Restricted Agenda • SDLC and Quality Standard • What is SDLC and Stages • Phases of SDLC • SDLC Models
- 3. Page 3Classification: Restricted • What is SDLC and Stages • SDLC Models • Waterfall Model • V-Model • Spiral Model • Agile Model and Testing • Quality Standard • ISO(9001,14001,27001) • SEI-CMMI -- Level 1 – Performed -- Level 2 – Managed -- Level 3 – Defined -- Level 4 -Quantitatively Managed -- Level 5-Optimizing • IEEE • Class Assignment Module 2 – SDLC and Quality Standard
- 4. Page 4Classification: Restricted What is SDLC and Stages Software Development Life Cycle(SDLC) SDLC, Software Development Life Cycle is a process used by software industry to design, develop and test high quality software. The SDLC aims to produce a high quality software that meets or exceeds customer expectations, reaches completion within times and cost estimates The software development life cycle (SDLC) is a framework defining tasks performed at each step in the software development process.
- 5. Page 5Classification: Restricted Phases of SDLC • • Requirement Specification and • Analysis • Design • Coding • Testing • Implementation • Maintenance
- 7. Page 7Classification: Restricted Requirement Specification and Analysis User Requirement Specification (USR) Software Requirement Specification (SRS)
- 8. Page 8Classification: Restricted Design The output of SRS is the input of design phase. Two types of design - High Level Design (HLD) Low Level Design (LLD) .
- 9. Page 9Classification: Restricted • High Level Design (HLD) • List of modules and a brief description of each module. • Brief functionality of each module. • Interface relationship among modules. • Dependencies between modules (if A exists, B exists etc). • Database tables identified along with key elements. • Overall architecture diagrams along with technology details. • Low Level Design(LLD) • Detailed functional logic of the module, in pseudo code. • Database tables, with all elements, including their type and size. • All interface details. • All dependency issues • Error message listings • Complete input and outputs for a module.
- 10. Page 10Classification: Restricted Coding Developers use the LLD document and write the code in the programming language specified. Testing The testing process involves development of a test plan, executing the plan and documenting the test results. Implementation Installation of the product in its operational environment.
- 11. Page 11Classification: Restricted Maintenance After the software is released and the client starts using the software, maintenance phase is started. 3 things happen - Bug fixing, Upgrade, Enhancement Bug fixing – bugs arrived due to some untested scenarios. Upgrade – Upgrading the application to the newer versions of the Software Enhancement - Adding some new features into the existing software.
- 12. Page 12Classification: Restricted SDLC Models Waterfall Model Waterfall approach was first SDLC Model to be used widely in Software Engineering to ensure success of the project. In "The Waterfall" approach, the whole process of software development is divided into separate phases. In Waterfall model, typically, the outcome of one phase acts as the input for the next phase sequentially.
- 14. Page 14Classification: Restricted • 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. Waterfall Approach - Advantages
- 15. Page 15Classification: Restricted • 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 documentation 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. Waterfall Approach - Disadvantages
- 16. Page 16Classification: Restricted Spiral Model The spiral model has four phases. A software project repeatedly passes through these phases in iterations called Spirals. • Identification: This phase starts with gathering the business requirements in the baseline spiral. In the subsequent spirals as the product matures, identification of system requirements, subsystem requirements and unit requirements are all done in this phase. • Design: Design phase starts with the conceptual design in the baseline spiral and involves architectural design, logical design of modules, physical product design and final design in the subsequent spirals. • Construct or Build: Construct phase refers to production of the actual software product at every spiral. In the baseline spiral when the product is just thought of and the design is being developed a POC (Proof of Concept) is developed in this phase to get customer feedback. • Then in the subsequent spirals with higher clarity on requirements and design details a working model of the software called build is produced with a version number. These builds are sent to customer for feedback. • Evaluation and Risk Analysis :Risk Analysis includes identifying, estimating, and monitoring technical feasibility and management risks, such as schedule slippage and cost overrun. After testing the build, at the end of first iteration, the customer evaluates the software and provides feedback.
- 18. Page 18Classification: Restricted V-Model Under V-Model, the corresponding testing phase of the development phase is planned in parallel. So there are Verification phases on one side of the .V. and Validation phases on the other side. Coding phase joins the two sides of the V-Model.
- 19. Page 19Classification: Restricted Big Bang Model • Big bang model comprises of focusing all the possible resources in software development and coding, with very little or no planning. The requirements are understood and implemented as they come. Any changes required may or may not need to revamp the complete software. • This model is ideal for small projects with one or two developers working together and is also useful for academic or practice projects. It.s an ideal model for the product where requirements are not well understood and the final release date is not given Pros Cons •This is a very simple model •Little or no planning required •Easy to manage •Very few resources required •Gives flexibility to developers •Is a good learning aid for new comers or students •Very High risk and uncertainty. •Not a good model for complex and object- oriented projects. •Poor model for long and ongoing projects. •Can turn out to be very expensive if requirements are misunderstood