Question Bank Essay

What is Softw atomic number 18 Development Life Cycle? (SDLC) (2 mks) outrankment Development Life Cycle (SDLC) is the overall operation of developing information musical arrangements through a multi-step process from investigation of initial requirements through analysis, design, performance and maintenance. b) Draw a diagram for pure waterfall sprightliness cycle. (5 mks) pic c)Explain the contrasting kinds involved in waterfall life cycle. (8 mks) point I Modeling Phase In this chassis we view the package product as part of a larger agreement or organization where the product is required.This is basically a body view where all the emergement elements are created. Phase II computer software program package Requirements Analysis Here we concord a human body where the requirements are gathered. The information field of operation for the software is understood. The function, behaviour, performance and interfacing of the software are determined. The requirements of the software and the node are decided upon. Phase one-third number This determines the data structures, the software architecture, the interface representations and the procedural (algorithmic) detail that goes into the software. Phase IV Code propagationHere the actual programming is done to obtain the machine code it is an implementation of the design. Phase V mental testinging The interrogatory is a process that goes hand in hand with the production of the machine code. thither are a number of examen strategies. First unit examination is done and then consolidation testing. Alpha testing is to look on if the software is as per the analysis model whereas beta testing is to see if the software is what the customer wanted. Phase VI Installation The software is released to the customer. Phase VII Maintenance This is the largest phase of the software life cycle.Maintenance move be of different types to modify the software as the requirements of the customer evolve, to remove the residual bugs in the software etc. 2)What is feasibility study? What are the contents we should get in the feasibility report? (5 mks) A feasibility study is an initial look at an alive information processing system to decide how it might be computerized or improved. The contents that a feasibility report are A statement of purpose of the system. A definition of system scope. A distinguish of deficiencies of the current system. A statement of user requirements.The cost and benefits of increment. A conclusion and recommendations. 3)What are the purposes of Data merge diagrams, Entity-Relationship diagrams? Give an role model diagram of for each one. (10 mks) Data Flow Diagrams Data Flow diagrams are a mover of representing a system at any level of detail with a graphic network of symbols video display data flows, data stores, data processes, and data sources/destinations. The purpose of data flow diagrams is to provide a semantic bridge between users and systems developers. The diagrams are Graphical Eliminating thousands of words Logical representations Modeling WHAT a system does, kind of than physical models showing HOW it does it Hierarchical showing systems at any level of detail and Jargonless allowing user correspondence and reviewing. pic Entity Relationship Diagram E-R Diagram is a graphical representation of the data layout of a system at a high level of abstraction. It defines data elements and their inter-relationships in the system pic 4)What is data modeling? Give 5 examples for data modeling. (5 mks) Data modeling is the act of exploring data-oriented structures.Like other modeling artifacts data models tail be used for a variety of purposes, from high-level abstract models to physical data models. From the point of view of an object-oriented developer, data modeling is conceptually similar to class modeling. With data modeling you invest entity types whereas with class modeling you identify classes. Data a ttributes are assigned to entity types just as you would assign attributes and operations to classes. Examples for data modeling admit Entity-Relationship diagrams Entity-Definition reports Entity and attributes report Table definition report Relationships, inheritance, composition and aggregation. 5)What is the difference between SRS memorial and design document? What are the contents we should contain in the SRS document and design document. SRS Document SRS document is a bid between the development team and the customer. Once the SRS document is approved by the customer, any subsequent controversies are settled by referring the SRS document. SRS document defines the customers requirements in terms of Functions, performance, external interfaces and design constraints. SRS Includes operating(a) Non functional User Interface System Design Document The purpose of a design is to eviscerate how the enhancements volition be incorporated into the live project. It should cont ain samples of the finished product. This could include navigational mechanism screenshots, example reports, and component diagrams. Design Includes E-R Diagrams Data flow diagrams Data Dictionary 6)Explain all the phases involved in the implementation phase. (10 mks) Conduct system Test In this test software packages and in house programs have been installed and tested, we ingest to conduct a final system test.All software packages, custom- built programs, and many an(prenominal) existing programs that make up the naturalfound system must be tested to ensure that they all work together This line involves analysts, owners, users, and builders. Prepare Conversion Plan On successful completion of system test, we can begin preparations to identify the new system into operation. Using the design specifications for the new system, the system analyst will develop a detailed conversion plan. This plan will identify Database to be installed, end user training and certificate t hat needed to be developed, and a strategy for converting from the old system to the new system.The conversion plan whitethorn include one of the following comm alone used instauration strategies 1)Abrupt Cut-over 2)Parallel Conversion 3) attitude Conversion 4) Staged Conversion Install Databases In the previous phase we built and tested the database. To place the system into operation we need fully loaded databases. The purpose of this task is to populate the new systems databases with existing database from the old system. System builders play a primary role in this activity. Train Users Converting to a new system necessitates that system users be trained and provided with documentation that guides them through using the new system.Training can be performed one on one however group training is preferred. This task will be completed by the system analysts and involves system owners and users. Convert to New System Conversion to the new system from old system is a significant miles tone. After conversion, the ownership of the system officially transfers from the analysts and programmers to the end users. The analyst completes this task by carrying out the conversion plan Recall that the conversion plan includes detailed installation strategies to follow for converting from the existing to the new production information system.This task involves the system owners, users, analysts, designers, and builders. 7)List and explain different types of testing done during the testing phase. (10 mks) whole Involves the design of test cases that validate that the immanent program logic is operation properly, and that program inputs produce valid outputs. All decision branches and internal code flow should be validated. Unit testing involves the use of debugging technology and testing techniques at an application component level and is typically the tariff of the developers, not the QA staff. IntegrationAs the system is integrated, it is tested by the system developer fo r specification compliance. Concerned with testing the system as it is integrated from its components Integration testing is normally the most expensive activity in the systems integration process Should focus on Interface testing where the interactions between sub-systems and components are tested post testing where system properties such(prenominal) as reliability, performance and usability are tested System Testing the system as a whole to validate that it meets its specification and the objectives of its users.The testing of a complete system preceding to delivery. The purpose of system testing is to identify defects that will nevertheless surface when a complete system is assembled. That is, defects that cannot be attributed to individual components or the interaction between two components. System testing includes testing of performance, security, mannequin sensitivity, startup and recovery from failure modes. Involves test cases designed to validate that an application an d its supporting hardware/software components are properly processing business data and transactions.System testing requires the use of regression testing techniques to validate that business functions are meeting defined requirements. Black street corner This is testing without knowledge of the internal workings of the item be tested. For example, when black stripewood testing is applied to software engineering, the quizzer would only know the legal inputs and what the expected outputs should be, but not how the program actually arrives at those outputs. It is because of this that black box testing can be considered testing with respect to the specifications, no other knowledge of the program is necessary.For this reason, the quizzer and the programmer can be independent of one another, avoiding programmer bias toward his own work. snow-white recess Also known as glass box, structural, clear box and open box testing. White Box is a software testing technique whereby explicit knowledge of the internal workings of the item being tested are used to select the test data. Unlike Black Box testing, white box testing uses specific knowledge of programming code to examine outputs. The test is accurate only if the tester knows what the program is supposed to do.He or she can then see if the program diverges from its think goal. White box testing does not account for errors caused by omission, and all visible code must besides be readable. 8)List and explain all the phases involved in the construction phase. (10 mks) figure of speech and Test Networks In many cases new or enhanced applications are built around existing networks. If so there is no problem. However if the new application calls for new or modified networks they must normally be apply before building and testing databases and writing or installing computer programs that will use those networks. This phase involves analysts, designers and builders A network designer and network administrator as sume the primary responsibility for completing this task. Build and Test Databases This task must immediately precede other programming activities because databases are the resource divided up by the computer programs to be written. If new or modified databases are required for the new system, we can now build and test those databases. This task involves system users, analysts, designers, and builders. The same system specialist that designed the database will assume the primary responsibility in completing this taskInstall and Test New Software Packages Some systems solutions may have required the purchase or lease of software packages. If so, once networks and databases for the new system have been built, we can install and test the new software. This activity typically involves systems analysts, Designers, builders, vendors and consultants. Write and Test New Programs In this phase we are ready to develop any programs for the new system. Prototype programs are frequently co nstructed in the design phase. However, these prototypes are rarely fully functional or incomplete.This task involves the system analysts, designers and builders. 9)What is data conversion? Why is it necessary? Data Conversion is the changing of the data structure to deem new or different needs for the data. Different operating systems have different application software, and each application normally has its own internal way of saving data. There are some standards such as CSV files for databases and RTF files for word processing text, however, these are few and far between and often only go on the basic information rather than the full structure. 10)What is change management?Computer based systems are dynamic. As the business Environment changes, there is a need of some changes to the information system. The changes occur not only during the study, design, and development phases of the life cycle of the system. In this process there are two elements that are necessity to the ma nagement of change. The performance review board, which can make managementlevel decisions about system modifications. service line documentation, which can be referred to, to determine the extent and impact of proposed modifications. 11)What is user acceptance testing?Explain different testings in user acceptance testing. Why is it necessary? User Acceptance Testing is a phase of software development in which the software is tested in the literal world by the intended audience. Different testings are Alpha Testing Alpha testing is the software prototype stage when the software is first able to run. It will not have all the intended functionality, but it will have core functions and will be able to accept inputs and generate outputs. An alpha test usually takes place in the developers offices on a separate system. Beta TestingThe beta phase of software design exposes a new product, which has just emerged from in-house (alpha) testing, to a large number of real people, real hardwa re, and real usage. Beta testing is not a method of getting free software long-term, because the software expires before long after the testing period. User acceptance testing is used to know if the system is working or not (both clients in-house) 12)What are functional and non-functional requirements? Functional How the system should react to the detail inputs How the system should behave to the particular situations What the system should not doNon functional Constraints on the services or functions Time constraints Constraints on the development process 13)Explain the steps involved in the prototyping 1. Define the goal and purpose of the prototyping. 2. Make plans for iterations (number, range) and evaluations (dates). 3. Transform the conceptual design to a first outline of the user interface and a first synopsis for the users information. 4. Design the paper prototype. 5. Let domain experts review the paper prototype regarding completeness and correctness. 6. Test the prototypes usability.