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Implementation and maintenance




After the plan for an information system is approved, it’s time to start building it. The implementation phase can include such activities as: purchase and install hardware and/or software, create applications, test applications, finalize documentation, train users, convert data, convert to new system.

Application testing is performed in three ways: unit testing, integration testing, and system testing. Unit testing and integration testing are usually performed in a test area. A test area might be located in an isolated section of storage on the computer system that runs the organization’s regular information system, or might be located on an entirely separate computer system. When a problem is discovered during unit testing or integration testing, the team must track down the source of the problem and correct it. Unit testing and integration testing are then repeated to make sure the problem is corrected, and no new problems were introduced when the original problem was fixed.

The data for a new information system might exist in card files, file folders, or an old information system. This data must be loaded into the new system - a process called “data conversion”. When converting data from a manual system to a computer system, the data can be typed or scanned electronically into the appropriate storage media. When converting data from an existing computer system to a new system, a programmer typically writes conversion software to read the old data and convert it into a format that is usable by the new system.

System conversion refers to the process of deactivating an old information system and activating a new one. It is also referred to as “cutover” or “go live”. There are several strategies for converting to a new system. They are a direct conversion, a parallel conversion, a phased conversion, a pilot conversion.

A new or upgraded information system undergoes a final test called acceptance testing. It includes the use of real data to demonstrate that the system operates correctly under normal and peak data loads. The term “maintenance phase” is a bit misleading because it seems to imply that the information system is maintained in a static state. On the contrary, during the maintenance phase, an information system is likely to undergo many changes to meet an organization’s needs. They can include the following: upgrades to operating system and commercial software, user interface revisions to make the system easier to use, application software revisions to fix bugs and add features, hardware replacements to enhance performance, security upgrades. The maintenance phase is the most expensive because it is the longest and it lasts until the system is retired.

To combat an escalating number of viruses, worms, Denial of Service attacks, and intrusions, security has become a top priority for the maintenance phase of an information system’s life cycle. Maintaining security is an ongoing activity. A system operator and a systems programmer are responsible for system maintenance. Even after in-depth training, employees sometimes forget procedures or have difficulty when they encounter a new set of circumstances. Many organizations establish a help desk to handle end-user problems. For example, suppose you encounter a problem with an update procedure and call the help desk. The help desk technician begins to troubleshoot the problem and soon realizes that it is caused by a programming error not caught during system testing. This bug is recorded in a “bug report” that is routed to the programming group, which can determine its severity and take steps to fix it.

 

Comprehension check. Match the beginnings of the sentences in the first column with the endings in the second.

1. Unit testing and integration testing are 2. When a problem is discovered during unit testing or integration testing 3. System conversion refers 4.When converting data from an existing computer system to a new system 5. A system operator and a systems programmer are 6. The help desk technician begins   a) responsible for system maintenance. b) a programmer typically writes conversion software to read the old data and convert it into a format that is usable by the new system. c) usually performed in a test area. d) the team must track down the source of the problem and correct it. e) to troubleshoot the problem and soon realizes that it is caused by a programming error not caught during system testing. f) to the process of deactivating an old information system and activating a new one.

 

Vocabulary practice

1. Put the letters in the following words into the correct order.

sienncovor ruvis sinrution shoyubtleroot cascumcriten agerost

 

2. Fill in the blanks choosing from the variants given.

1. Application testing is performed in three ways: integration testing, unit testing and ….

a) data testing b) program testing c) system testing

2. When a problem is discovered during unit testing or integration testing, the team must … the source of the problem and correct it.

a) investigate b) produce c) include

3. Unit testing and integration testing are repeated to make sure the problem is ….

a) activated b) converted c) solved

4. System conversion refers to the process of deactivating an old … system and activating a new one.

a) information b) operating c) support

5. An information system is likely to undergo many … to meet a company’s needs.

a) changes b) formats c) systems

6. Many organizations establish a help desk … end-user problems.

a) to divide b) to manage c) to enlarge

7. The help desk technician begins to troubleshoot the problem and soon … that it is caused by a programming error not caught during system testing.

a) forgets b) repeats c) understands

3. Match the beginnings and the endings of the instructions/steps given and put them into correct order.

1. Create debugger as a system software that helps programmers 2. After that write the specifications and design the computer system and the methods for the information system 3. Write the program in a specific programming language, that specifically refers 4. Depending on the organization and its size, the systems analyst’s tasks are 5. Next step is to interview the people who will be using the system 6. With the help of testing and acceptance, make sure the system works properly and 7. Then determine which people and what kind of software, hardware, and monetary resources are 8. Keep system working properly and, if business procedures or conditions are changed, a) to determine their needs, problems, and expectations. b) to solve the problem. c) turn it over to the users with accompanying training, as necessary. d) to writing source code. e) necessary or available to solve the problem. f) to analyze the problem to be solved, the data to be input, the expected output, and other system considerations. g) to identify errors. h) improve them.

 

4. Fill in the gaps in the text.

During the _ 1 _ phase of the SDLC, the project team supervises the technicians who set up new hardware, install programming languages and other application _2_ tools, create and test applications, and customize software. The team also finalizes the system documentation and trains users. In this phase, three types of testing ensure that new software works correctly. _3_ testing is performed on each module, and then _ 4 _ testing is performed to make sure that all of the modules work together correctly. _ 5_ testing ensures that the software components work correctly on the hardware and with other, perhaps older, elements of the information system.

When application testing is complete, data is converted from the old system to the new one, users are trained, and the new system goes live. Four types of information system “go live” conversions are possible. At the end of the conversion process, the information system undergoes a final test called _ 6 _ testing, designed to assure the system’s owner that the new system works as specified.

After installation, an information system enters the _ 7_ phase of its life cycle.

Speaking. Discuss the following questions.

1. Does a new information system typically require new hardware?

2. What is the next step in the implementation phase?

3. What is application testing?

4. What documentation does the project team create during the implementation phase?

5. How do employees learn how to use the new information system?

6. How does a business switch from the old information system to the new system?

7. What happens during the maintenance phase?

8. How important is system security during this phase?

9. Who is responsible for system maintenance?

10. Why do maintenance activities include user support?

 

Critical thinking. Read the article and express your opinion on the problem.

Online Voting

The idea of online voting surfaced years ago as the Internet gained popularity. The term online voting usually refers to a remote voting system that allows voters to cast their ballots from any computer connected to the Internet.

Because of its advantages, online voting has the potential to attract net-savvy young voters who historically have voted in lower numbers than other segments of the population. It also simplifies the voting process for elderly and homebound voters. The convenience of online voting might also increase participation in local elections.

Online voting has the potential to decrease the number of ballots that are invalidated because of procedural problems, such as failing to completely punch out the “chad” on a ballot card, or checking more than one candidate on a paper ballot. Voting software can prevent voters from erroneously selecting more than one candidate and make sure that voters can revise their selections without invalidating their ballots.

Although there are plenty of supporters of this form of elections there are lots of opponents because of the risk of some technological issues with Internet security.

In addition to them online voting opponents have concerns about voter fraud and privacy.

For a democracy to function properly, its citizens should be confident that the electoral system is honest and works. Online voting presents some sticky technological and social challenges. Although these challenges exist, secure technologies for online banking and e-commerce are working, so shouldn’t it be possible to design an online voting system that's secure enough to conduct our elections?

 

What do you think?

1. Would you prefer online voting to voting at a polling place?

2. Should online voting be available only to specific groups of people who currently have trouble reaching polling places?

3. What technical issues can online voting face and how to solve them?

Projects. Perform the project given.

 

1. Form a group of two to five students as the project team for a systems development project. Elect one person as the team leader, who will assign tasks to each group member. Your team’s mission is to complete the planning phase for a systems development project and produce a Project Development Plan. The first task is to identify and briefly describe an information system at school, work, or local business that needs improvement. The second task is to make a list of problems and opportunities that exist in that system. The third task is to make a list of tasks your team would perform, to design, construct, and implement a new information system. Finally, incorporate all your findings into a document that would serve as the Project Development Plan. Submit this plan to your instructor, who might provide additional directions for your group work and report format.

2. Create 10 rules for an expert system that pertains to your career field. To complete the assignment, think of a set of simple decisions that someone on the job might be required to perform. For example, a loan officer might be required to make a quick evaluation of a borrower, an auto mechanic might be required to figure out what various tapping noises mean, or a fitness instructor might be required to recommend the best type of fitness class for clients. Make a list of 10 rules that would help make the decision. The rules should be in the format IF…THEN…Submit your rules to your instructor.

 

 

Final test. Do the tasks in the following test.

 

1. In the analysis phase, the project team determines how the new information system will meet the requirements. (True/False)

2. A … tool is a software application that is designed for documenting system requirements, diagramming current information systems, scheduling development tasks and developing computer programs.

3. The process of planning and building a new information system is referred to as systems … and design.

4. The goal of the…phase is to produce a list of requirements for a new or revised information system.

5. A Project Development Plan typically must be approved by the management before a project proceeds beyond the planning phase. (True/False)

6. In an information system context, a … is an exchange between two parties that is recorded and stored in a computer system.

7. Generally most transaction processing systems provide managers with detail reports that contain all the information needed to understand and analyze data. (True/False)

8. A transaction … system provides a way to process, store, display, modify, or cancel transactions.

9. During the … phase, the project team supervises the tasks necessary to construct the new information system.

10. If you have a question about the information system you are using, the first step to finding the answer is to call the help desk. (True/False)

11. In the … phase, the project team identifies potential solutions, evaluates these solutions, and then selects the best solution.

12. If a project- team selects turnkey solution the next step would be to have the team’s system analysts create a set of application specifications. (True/False)

13. … processing using client/server or peer-to-peer architecture provides high level processing power at a low cost.

14. Which of the following documents ask a vendor both to recommend hard ware and software for an information system solution and to provide the vendors qualifications to implement the solution.

a) request for quotation c) request for solution

b) request for qualifications d) none of the above

15. Which type of transaction processing systems collects and holds a group of transactions for processing until the end of a day or a pay period.

a) online processing c) group processing

b) batch processing d) rollback processing

16. Unit testing is normally performed in a test area. (True/False)

17. Which phase of an SDLC is usually the most expensive?

18. The analysis phase concludes when the System Requirement Report is written. (True/False)

19. An expert system uses fuzzy logic to deal with imprecise data by asking for a level of confidence with an OLTP system, if one step fails during the transaction, the record will … to their original state.

20. All of the following activities take place during the implementation phase EXCEPT.

a) purchasing and installing software c) revising software as necessary to

meet business needs

b) creating applications d) testing applications

 

 


 

 

Unit 7. DATABASES

Text A

Reading. Read the text and try to guess the meaning of the words in bold. Check your variants in the dictionary.





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