Cleanroom Software Engineering By NADEEM AHMED FROM DEPALPUR

Hello friends today my topic is on cleanroom Software Engineering.

1. What is cleanroom It is a type of software development approach where most of the developers follow this approach to develop software with certified reliability. This cleanroom deny the entry of defects during the development of software. It avoids copyright infringement litigation. Formal design and requirements methods .

2. Introduction It is straight forward technique CR is an approach that emphasis on developing quality software with the help of statistical and mathematical techniques. In short verifying the correctness of every phase before testing. It fully based on formal methods.

3. CR Methodology

4. Why is it important Quality Most suitable for critical applications Increased productivity Reduces cost Team oriented increment pipelining allows for many component to be worked on concurrently therefore increasing productivity.

5. Cleanroom Reference Model

6. Model….. Cleanroom uses a specialized version of increment process applying pipelining techniques. Each increment is eventually added together to create the entire system Follows 7 steps process for each increment assuring that each component is certified reliable before moving on to the next component.

7. Cleanroom Methods Steps

8. 1).Increment planning Detail description of customer level requirement is described for each functional increment. All the increment is defined and planned beginning to end. It simplify the customer concepts.

9. Incremental Modal

10. 2).Requirement gathering Requirement gathering is done by using the traditional techniques like analysis, design, code and test. A more detailed description of the customer level requirement is developed.

11. 3).Box Structure Specification Requirements have been established, the function and behavior of each increment must be defined. It uses a box structure specification to defined the product. The refining process begins from black box, refined to state box and then finally to clean box.

12. Box Structure…… Structure programing code Black Box State Box Clear Box

13. 3.1).The Black Box It represents an incremental component as a whole and sits at the top of a hierarchy of software components. The black box reacts to stimuli and uses transition mapping rules to determine a response.

14. 3.2).The State Box It seen as generalized state machine including state data and operations and incorporated the black box. It reacts to stimuli which causes a state transition and results in a response. State boxes are crucial for showing the behavior of a system and how it reacts and transitions due to user inputs.

15. The state Box

16. 3.3).The clear Box It breaks down the sub functions of the black box into procedural that resemble structure programing. It shows the component in high detail. At this stage,these specification are able to mathematically proven to be correct

17. 4).Formal Design Once box the structure specification is complete cleanroom designing takes place. Functions in clear box are systematically refined from mathematically functions to logical connectives that resemble to programing language.

18. 5).Correctness verification It allow them to be mathematically verified for correctness using mathematical proofs. Using general correctness condition depending on situation. Once all functions of a component are verified to be correct, coding implementation can begin.

19. 6).Statistical test planning Analyzed, planned and designed the projected Usage of the software. The cleanroom activity is organized in parallel with specification, verification and code generation.

20. 7).Statistical use testing The exhaustive testing of computer software of computer software is impossible. It is compulsory to design limited number of test cases. These sample are collected from the users from a targeted population.

21. Certification After the verification, inspection and correctness of all errors, the increment are certified and ready for integration.

22. Incrementation