Prototype Model

SOFTWARE ENGINEERING NOTES PART 2 PROTOTYPE MODEL Prototype model (prototype model) is an activity in which prototypes of software applications are created. First the prototype is manufactured then based on that prototype the final product is manufactured. The prototype model was developed to overcome the shortcomings of the waterfall model. This model is created when we do not know the requirements well. The specialty of this model is that this model can be used with other models as well as alone. One problem in this model is that if the end users are not satisfied with the prototype model, then a new prototype model is made again, due to which this model takes a lot of money and time. The prototype model consists of the following phases: 1: - Requirement gathering: - The first step of the prototype model is to collect the requirements, although the customer does not know much about the requirements, but the main requirements are defined in detail. 2: - Build the initial prototype: - Initial prototype is built in this phase. In this, some basic requirements are displayed and the user interface is made available. 3: - Review the prototype: - When the construction of the prototype is completed, it is presented to the end users or customer and feedback is taken from them about this prototype. This feedback is used to further improve the system and make possible changes to the prototype. 4: - Revise and improve the prototype: - When feedback is taken from end users and customers, the prototype is improved on the basis of feedback. If the customer is not satisfied with the prototype, a new prototype is made and the process continues until the customer gets the prototype as desired. Mc’CABE’S COMPLEXITY McCabe's complexity is called cyclomatic complexity. This is a software metric, this complexity is used to find out the complexity of the software program. Cyclomatic complexity measures the number of independent paths directly through the program's source code. The greater the number of independent paths, the more complex the code. Independent paths are those paths which have at least one edge and which have not been traversed before. This complexity was proposed by Thomas McCabe in 1976. This can be understood mathematically in the following way: [McCabe's complexity V(G) = E – N + 2] Where; E = number of edges N=Number of Vertices P=number of disconnected paths. properties of McCabe's complexity:It has the following properties:1 :- V(G) >= 1 2:- V(G) is the maximum number of independent path in the graph. 3:- If V(G)=1 then there will be only one path in the graph. 4: - It reduces the complexity by 10. COCOMO MODEL Its full name is constructive cost model, it was proposed by BOEHM in the year 1981. It is a cost estimation model and it is used to evaluate the cost of software packages. In this model, the effort equation is used to estimate the number of person-months needed to develop a project. According to BOEHM, three stages are used to estimate the cost, which are as follows: W hat is v model What is spiral model? What is SDLC model? Basic COCOMO model This model is static and single-valued, which computes software development effort and cost as the program size of the function, and the program size is expressed in estimated lines of code (LOC). Generally this model is used in small and medium sized software projects. The following formula is used to estimate the cost in this model:- Where; *KLOC is the approximate size of the software. * a1, a2, b1, b2 are constants for each category of software. *Tdev is the estimated time to develop the software. Effort is the total effort put into developing the software. *PM is person-month. Intermediate COCOMO This model is an extension of basic COCOMO. Intermediate COCOMO computes software development effort as a function of program size and a set of cost drivers. Cost drivers determine the time and effort involved in the project. This model gives better results than the basic model because cost drivers are used in it. Complete COCOMO This model is an extension of the intermediate Kokomo. This model differs from the intermediate model because it uses effort multipliers for each phase of the project. In complete Kokomo, the cost of each subsystem is estimated separately. The errors due to this method are very less. The shortcoming of basic and intermediate COCOMO is that it treats the software project as a single homogeneous entity. Complete Kokomo removes this shortcoming. Uses very complex procedures to calculate the complete COCOMO estimation. SOFTWARE QUALITY Software quality means that the software should be error free, meet the requirements, be delivered on time and come within the budget and its performance should be of high quality. Software quality is based on the external and internal quality of the software. External quality means what does a user experience when he runs the software? While internal quality is based on such an aspect which is code-dependent and this code is not visible to endusers, it has nothing to do with coding. The following are the external and internal quality of the software:1:- Ease-of-use:- The software should be easy to run i.e. the user-interface of the software should be better. 2:-Design:- The design of the software should be good because the user will be attracted towards the software only when its design is better. 3: - Speed (speed): - The software should provide its service by spending less time, that is, its speed should be fast. 4: - Security: - The software should be secure, that is, who can see and process the data present in the software? If there is any internet based software then it should have encryption and decryption. 5:-Error-free:- The software should be free from errors because if there are errors in the software, then the reliability and security of the software will decrease due to which the software will fail. 6:-Portable:-Software should be portable, that is, software should run easily on other environments as well. 7:-Testability:- Testability means that the software can be easily tested. 8: - Maintainability: - It means that if we have to make any changes in the software, then we can do it easily. 9: - Readability: - The source-code of the software should be readable, that is, which can be read easily. 10: - Reliability: - Software should be reliable, that is, the software which is there should be stable on its performance. 11: - Functionality: - That is, the software that is there should have functions based on the needs of the user so that the user can easily work in it. There are many criteria to measure software quality and each aspect has its own importance. SQA The full form of SQA is software quality assurance. SQA is a set of activities that ensure that quality is present in the software developed. SQA is a process within the Software Development Life-Cycle (SDLC) that periodically examines the methods and processes used for software quality. WALKTHROUGH This is an informal review and does not require any preparation. In this, a designer or programmer leads the development team and the participants ask questions about possible errors in the software, violations of software standards and other problems and also give suggestions for those problems. . Walkthrough is generally organized by the author. In this, the author reads the software product code and other team members tell the errors and suggestions present in it. Purpose of Walkthrough:It is conducted for the following purpose:1: - It is used to find errors. 2: - It is used to discuss alternative solutions to problems. 3: - It focuses on how to meet the requirements of the software. There are three main experts in the walkthrough which are as follows:1:-Author:-In the walkthrough meeting the author presents the software product and the author handles the responsibility of completing the work. 2:-Leader:-It is organized by the leader, the leader does all the administration work. 3: - Recorder: - Recorder works to record all the bugs, defects, and decisions, actions to be taken in the walkthrough meeting. SOFTWARE TESTING INSPECTION Inspection is a formal review and requires preparation. Inspection was done in 1976 by M.E. Fagon was the first to define. For this reason it is also called Fagon Inspection. Defects are detected and corrected by inspection. It is led by a trained Moderator. Moderator is not an author. In inspection, a software product is selected for review and an inspection team is assembled to review this software product. Purpose of Inspection:It has the following objectives:- 1: - Its purpose is to detect and correct the defects coming in the software product. 2:- Improving the quality of the software. Steps of Inspection:The process of inspection consists of the following steps:- 1:-Planning:-The entire planning of the inspection is done by the moderator and the work of the moderator is to peer-review the software product. 2: - Overview: - In this the author describes the background of the software product. 3:-Preparation:-This is an individual activity; In this, each inspector checks the software product and identifies possible defects. In this defects are only noted but not collected. 4:-Meeting:-It is operated by the moderator. Each part of the software is read sequentially in the meeting. Defects are collected in this. 5: - Rework: - It is executed by the author. Changes are made in the software product according to whatever is planned during the meeting. 6:-Follow-up:-In this, the changes made by the author are checked to see whether the changes made are correct or not. FORMAL TECHNICAL REVIEW FTR is an activity of Software Quality Assurances (SQA) which is performed by software engineers. Through FTR, possible faults or defects are identified in the software product. It would be better if the defects are identified beforehand because it becomes very difficult to find and correct them later. In this, the product is analyzed to improve the quality of the software product. Purpose of FTR:It is used for the following purposes:1: - To detect errors. 2: - To verify the requirements of the software. 3:- To see whether the software is developed correctly or not. 4: - To ensure that the software product is represented according to the already decided standards. 5:-To make the project more systematic. Walkthroughs, inspections and formal reviews etc. come inside the FTR. In the end, I would like to say that “Any FTR can be successful only when it is properly planned, controlled and attended. If this post has been helpful for you, then you can share it with your friends. If you have any suggestions or questions, then you can tell through comment. CAPABILITY MATURITY MODEL The full name of CMM is capability maturity model. This is a model that is used to develop the software of the organization and to improve the already developed software. This model was developed by SEI (software engineering institute) in the year 1986. In many organizations, software projects become very late and their budget also becomes high, due to which the project becomes undisciplined (undisciplined) and disorganized. To solve this problem, SEI had to manufacture the CMM. The capability maturity model (CMM) guides software organizations on how to control the processes used to develop and maintain software. CMM software is based on the knowledge obtained from project evaluation and feedback received from government and industry. In this, organizations are given CMM rating by auditors according to their capability. Nowadays it is called CMMI (capability maturity model intergation). There are 5 levels of software process maturity, which are as follows. 1:-Initial level:This is the first level of cmm. This level is very unpredictable and badly controlled. Conditions are not stable for developing software in this level because there is no standard of organization. Any software project can be successful only when the manager and programmer work well and the success will remain till they work together in the next project as well. But if either of these two leaves the organization then the quality of the project declines. One of the main reasons for the decline in the quality of the project is not testing properly. 2:-Repeatable level:This is the second level of cmm. In this, for the success of software development, the process is repeated ( reapeat) which gives consistent results. In this, project management techniques are used for the continuous success of the project. In this, the management and planning of new projects is done on the basis of experience of similar projects. 3:-Defined level:This is the third level of cmm. In this, the standard processes used in developing and maintaining the software of the organization are documented and established. These standard processes are improved over time so that the performance of the software project is always consistent. With the establishment of processes, programmers, managers and other technical staff can work well and can easily control the cost, schedule and functions of the software project. 4:-Managed level:This is the fourth level of CMM. In this, the organization sets goals for both software products and processes. In this, the quality of the project is of high quality and the performance is always consistent and predictable. In this, sub-processes are selected for software development, which have full cooperation in the performance of the entire processes. The chosen sub-process is controlled by statistical and other quantitative techniques. 5:- Optimizing level:This is the last level of cmm ie the fifth level and attention is paid to the improvement of the process. Reduces possible errors and mistakes to improve the process and also reduces the cost of software development. Advantage of CMM:Following are some of the advantages of CMM:1: - One of its advantages is that the people of programmer, manager and technical staff always give priority to quality. 2:- The cost is very less in this because there are very few defects and errors in the software project. 3: - This increases the productivity of the software product. 4: - Most of the customers are benefited by which they are satisfied. 5:- It increases the predictability and consistency of the software project. 6: - Through this the software process is improved. TOTAL QUALITY MANAGEMENT TQM is a management technique or method in which continuous efforts are made to improve the quality of processes, quality of products and all activities. Simply put, "It is a process in which continuous efforts are made by the management and all the employees of the organization / company to provide better service to the customer." The role of employees from top to bottom in the organization is in providing quality products and providing good service to the customer and TQM is not based on any particular project and product, but it is based on the entire organization. It is a process in which errors and defects are removed and better facilities are provided to the customer. It should always be remembered that when any customer is happy or satisfied with the product of a company, then he tells more people about that product and company, then more people join him. That's why total quality management is very important. TQM starts by keeping the customer first and never ends because its lifetime commitment is to continuously improve the quality. It was developed by William Deming in 1980 and it is called "Total Quality Management" What is customer relationship management (CRM)? What is supply chain management (SCM)? TQM PROCESS Its process is divided into 4 parts:1:-PLAN 2:-DO 3:-CHECK 4:-ACT Means PDCA cycle. 1:- PLAN:- This is the first step of the PDCA cycle, in which problems are assessed and new plans are made on the basis of these problems. 2:-DO:- The plan that was made in this step is implemented. And whatever changes are made are documented to be evaluated. 3:-CHECK:- In this step the data obtained from the previous phase is checked. In this, it is seen whether the plan that was made has been achieved or not. 4:-ACT:- This is the last step of PDCA, in this step communication is done with other employees of the organization and new procedures are implemented by discussing with them. And the information about this new implementation is given to other people. The thing to remember here is that this is a continuous cycle, after the act step, the plan step comes again. Impact of TQM We can understand the effect of TQM through the picture given below:- “If the quality of the product is better then the productivity will increase, if the productivity increases then the cost will decrease and the profit will be more due to which business will increase and jobs, investment and competition will increase.” PRINCIPLES OF TQM Its principles are as follows;1:-Customer focus:- Decisions are taken in the company according to customer's requirements and on the basis of satisfaction and anyway any customer is satisfied when good quality product is available at low prices. “CUSTOMER IS KING” The customer is treated like a king. 2:- continuous improvement:- Another feature of TQM is to improve all the activities and it continues continuously. Determined and continuous efforts are made to improve the quality of the products. 3: - Employee involvement: - Employees are included in this because the quality in the product can be improved only by the employees. Because if the employees are empowered then they will be able to provide their service in a better way. “All people are included in this; ‘from the manager to the watchman, all the people’ because all the people have their own roles and responsibilities. 4: - Techniques and tools: - The use of technology and tools in the company is very important; With these the quality can be increased. Most employees use only one tool at a time, but sometimes using tools in combination proves to be very beneficial. 5:- Decision-making:- The decisions taken in the company should be based on facts and data and not on the basis of emotions and personal issues. 6:- Communication:- Communication is very important for any business to be successful. If there is no proper communication between the customers and the employees, then the business will be ruined. Advantage of TQM Its advantage is that the customer remains satisfied because the company has the best products and services, there is no mistake in them. And then the company gets a lot of profit because the customers themselves tell other people about that product. Due to this the defects (deficiencies) of the product are reduced. Because the main task of tqm is to improve the quality of the product, which makes the product very good. From this it is known that which product is needed in the market. This reduces the cost of the company.