Assignment

1.           Difference between Logical DFD and Physical DFD.

Logical vs Physical DFD

Logical DFD

·        Logical DFD depicts how the business operates.

·        The processes represent the business activities.

·        The data stores represent the collection of data regardless of how the data are stored.

·        It’s how business controls.

Physical DFD

·        Physical DFD depicts how the system will be implemented (or how the current system operates).

·        The processes represent the programs, program modules, and manual procedures.

·        The data stores represent the physical files and databases, manual files.

·        It show controls for validating input data, for obtaining a record, for ensuring successful completion of a process, and for system security.

2.           What is DFD? List out the Symbol used in DFD.

A level 2 data flow diagram (DFD) offers a more detailed look at the processes that make up an information system than a level 1 DFD does. It can be used to plan or record the specific makeup of a system.

The Symbol used in DFD

Data Store

Process

Entry

data flow

3.           State any explain the rules of creating zero level DFD with example

When creating data flow diagrams. There are certain rules which must be followed. This rules allow for the DFD to be make sense and also to be easily understood. In this blog I will go through the rules which must be followed and show practical examples of these rules.

1.      All data flows must flow to or from a process.

 All flows of data must be either coming from or going to a process. External entities can not flow directly to each other. A data flow can not link a data store to an external entity. Data can not move between data stores without first being processed.

 

 

4.           Explain various activity involve in system design.

A systemic approach is required for a coherent and well-running system. Bottom-Up or Top-Down approach is required to take into account all related variables of the system. A designer uses the modelling languages to express the information and knowledge in a structure of system that is defined by a consistent set of rules and definitions. The designs can be defined in graphical or textual modelling languages.

5.           Explain role of system analyst in system development process.

The systems analyst systematically assesses how users interact with technology and how businesses function by examining the inputting and processing of data and the outputting of information with the intent of improving organizational processes. Many improvements involve better support of users’ work tasks and business functions through the use of computerized information systems.

Our definition of a systems analyst is necessarily broad. The analyst must be able to work with people of all descriptions and be experienced in working with computers. The analyst plays many roles, sometimes balancing several at the same time. The three primary roles of the systems analyst are consultant, supporting expert, and agent of change.

6.           List any two common errors that are made while data flow diagrams.

DFDs look easy on the surface - after all, what's hard about writing down a few bubbles and arrows? In practice the techniques proves to be somewhat more difficult than one might initially anticipate. Obtaining appropriate names for both processing steps and data flows can require careful thought. As one rule of thumb, imagine that you are producing a diagram that must pass this test: you will finish the DFD, then hand it to someone (of reasonable intelligence) who will then proceed to describe the process back to you based upon what he or she sees in your diagram. If this process recitation captures your original process description (and, of course, the appropriate characteristics of the business process itself), your DFD is reasonably accurate.

7.           What is the purpose of system testing? What should be the output of the system testing?

System Testing means testing the system as a whole. All the modules/components are integrated in order to verify if the system works as expected or not. System Testing is done after Integration Testing. This plays an important role in delivering a high-quality product.

8.           Give one example each for strategic, tactical and operational decisions.

Strategic planning is an organization’s process of defining its strategy, or direction, and making decisions on allocating its resources to pursue this strategy. For example, the first and third questions are those that motivate an acquisition. Acquisitions are thus strategic choices. Typically strategic choices look at 3 to 5 years, although some extend their vision to 20 years (long term). Because of the time horizon and the nature of the questions dealt, mishaps potentially occurring during the execution of a strategic plan are afflicted by significant uncertainties and may lie very remotely out of the control of management

9.           How cost-benefit analysis plays an important role in SDLC?

There is always something that needs executing, and often that something is critical to the success of the venture. Because of the high stakes, good managers don’t just make decisions based on gut instinct. They prefer to minimize risk to the best of their ability and act only when there is more certainty than uncertainty. But how can you accomplish that in a world with myriad variables and constantly shifting economics? The answer: consult hard data collected with reporting tools, charts and spreadsheets. You can then use that data to evaluate your decisions with a process called cost benefit analysis (CBA). An intelligent use of cost benefit analysis will help you minimize risks and maximize gains both for your project and your organization.

10.        What is the drawback of DFD

The biggest drawback of the DFD is that it simply takes a long time to create, so long that the analyst may not receive support from management to complete it. Physical considerations are left out. Advantages of data flow diagram: It aids in describing the boundaries of the system.

11.        List characteristics of a good interface.

8 Characteristics of Successful User Interfaces

·        Clear.

·        Concise.

·        Familiar.

·        Responsive.

·        Consistent.

·        Attractive.

·        Efficient.

·        Forgiving.

12.        Explain different ways in which an analyst gathers requirement from the customer.

Requirement Gathering is the first phase of the project and it’s also a key to successful projects. Missing or incomplete requirements lead the project nowhere, hence successful projects focus more on the requirement gathering process. Business Analyst is the person who generally gathers and analyses the requirements in order to fulfill the client’s needs. There are various methods to achieve your requirement gathering goal and it’s totally up to Business Analyst’s choice to pick one to finish the work.

13.        What is MIS? What are different components of MIS? Explain different categories of information required to serve the needs of different levels of management in an organization.

A management information system is made up of five major components namely people, business processes, data, hardware, and software. All of these components must work together to achieve business objects.

14.        What is DSS? Explain application of DSS in today’s world? What is the difference between MIS and DSS?

1	Primary Task	MIS identifies the information required.	DSS identifies the tools to be used in decision process.
2	Focus	Focus is on efficiency.	Focus is on effectiveness.
3	Database	Corporate Databases are used.	Special Database needed.
4	Data	Focus is on data storage.	Focus is on data manipulation.
5	Dependency	Dependent on computer.	Dependent on management jurisdiction.
6	Usage	MIS is used to in control process.	DSS is used in planning, staffing and decision making.
7	Users	MIS is used by middle level, low level users and senior executives in some cases.	DSS is used by analysts, professionals and managers.
8	Focus	Focus is on information processing.	Focus is on decision making, support and analysis.

15.        What is structured analysis? Name a tool that carried out structured analysis? Explain the tool.

Its graphical nature makes it a good communication tool between user and analyst or analyst and system designer. It gives an overview of what data a system processes, what transformations are performed, what data are stored, what results are produced and where they flow.

16.        Differentiate black box testing and white box testing. Can one be used in place of other? Give reasons.

In Black Box, testing is done without the knowledge of the internal structure of program or application whereas in White Box, testing is done with knowledge of the internal structure of program. Black Box test provides low granularity reports whereas the White Box test provides high granularity reports.

17.        How do tangible costs differ from direct costs?

Direct costs and variable costs are similar in nature and are both types of costs involved in production. Direct costs are expenses that can be directly traced to a product, while variable costs vary with the level of production output

18.        What are functional requirement and non-functional requirement?

While functional requirements define what the system does or must not do, non-functional requirements specify how the system should do it.  Non-functional requirements define system behavior, features, and general characteristics that affect the user experience.

19.        Explain Output Format types: Tabular format, Graphical format, Detailed Reports and Summary Reports with proper diagram and format.

Performance Reporting Manager provides four possible output formats for its reports Pie chart. All four format options are not available for every report. The type of  The tabular report option returns data in table format. The eight lines contained in the report are plotted in a graph with both an X-axis and Y-axis defined 

20.        What is in your opinion the most difficult job for system analyst?

Perhaps the most difficult task in system analysis is identifying the specific requirements that the system must satisfy. These requirements often are called user requirements because users provide them.  A computer systems analyst is an occupation in the field of information technology.

21.        Explain Open and Close System with example.

An open system is defined as a system in exchange of matter with its environment, presenting import and export, building-up and breaking-down of its material components. Closed systems, on the other hand, are held to be isolated from their environment.

22.        Explain Information Gathering Technique- Questionnaires?

The use of questionnaires is an information-gathering technique that allows systems analysts to study attitudes, beliefs, behavior, and characteristics of several key people in the organization who may be affected by the current and proposed systems.

23.        What are The Types of Feasibility?

There are five types of feasibility study—separate areas that a feasibility study examines, described below.

• Technical Feasibility. 
• Economic Feasibility.
• Legal Feasibility.
• Operational Feasibility.
• Scheduling Feasibility.

24.        What are The Types of Systems?

There are two major types: NATURAL SYSTEMS and DESIGNED SYSTEMS. Natural systems range from subatomic systems to living systems of all kinds, our planet, the solar systems, galactic systems and the Universe. The genesis of these systems is the origin of the universe and the result of the forces and events of evolution.

25.        In System Design process, what is Requirements Determination?

Requirements determination is the beginning sub phase of analysis. In this sub phase, analysts should gather information on what the system should do from as many sources as possible. Requirements structuring is the process to use some kind of systematical and standard, well-structured methods to model the real world.

27.        If an information system were to be designed for a retail grocery store/online e-commerce website, what would be the strategic, tactical, statutory and operational information?

Types of system documentation include a requirements document, source code document, quality assurance documentation, software architecture documentation, solution instructions and a help guide for advanced users. Types of user documentation include training manuals, user manuals, release notes and installation guides.

28.        Define deterministic and probabilistic system with example.

A deterministic model does not include elements of randomness. A probabilistic model includes elements of randomness. Every time you run the model, you are likely to get different results, even with the same initial conditions. A probabilistic model is one which incorporates some aspect of random variation.

29.        What are the major threats to system security? Write down the guidelines to control the access.

30.        What are the differences between initial investigation and feasibility study in system development life cycle? How can you relate them?

31.        “Fact Gathering” is a role of system analyst. Explain.

35.        What categories of information are relevant to decision making in business. Relate each category to the managerial level and information system.

36.        Give example of informal and formal system and also explain why they are called so?

37.        What additional information would you like to gather a second interview?

38.        A system analyst should be an "Analytical Mind", explain it.

39.        What are malware? Distinguish between DOS and DDOS attacks of a server? How to recover from those attacks?

40.        Briefly describe physical security and data security with example.

41.        What are computer crimes? Briefly explain at least three example of computer crimes happened in Bangladesh.

42.        What are the differences between open ended questionnaire and close ended questionnaire regarding information gathering tool?

43.        What are the steps an analyst should follow to design an information system? Explain with diagram.

44.        What is data dictionary? Why it is important regarding software project management?

45.        What is information gathering? How we gather information to analysis a system?Which of the following methods would you use and why?

46.        Elaborate on the steps taken in system testing that lead to the user's acceptance of the system.

47.        What is encryption? How does it work? What type of system would appropriate for this technology? Illustrate.

48.        Distinguish between software maintenance and enhancement.

49.        Talk to a book shop owner and find out what his information requirements are. Divide it into operational, tactical, strategic and statutory components. Describe how his operational and tactical information needs could be satisfied if he installs a PC.

50.        Specify the purpose of the system testing. What performance criteria are used for system
testing? Discuss.

51.        List five of the several measures an analyst can take to improve the security, privacy, and
confidentiality of data, systems, networks, individuals, and organizations that use ecommerce web applications.

52.       

How is disintermediation beneficial to customers in online shopping? Explain it with example.

53.        What are the unique features of electronic commerce (e-commerce), digital markets, and digital goods?

54.        What is the difference between quantitative data and qualitative data? In what situations could the number 10 be considered qualitative data?

55.        We all interact with various information systems every day: at the grocery store, at work, at university, even in our cars (at least some of us).

Write down the four different information systems you interact with every day. See if you can identify the technologies, people, and processes involved in making these systems work.