1. What is a system development life cycle?
2. How does an information project begin?
3. What does the planning phase entail?
4. Do computers offer tools for planning activities?
5. How does the project team determine what the new system should do?
6. How does the project team document system requirements?
7. What does the project team do with system requirements?
Text 23B. SYSTEM DESIGN
In the design phase of the SDLC, the project team must figure out how the new system will fulfill the requirements specified in the System Requirements Report. The project team should identify several potential hardware and software solutions by brainstorming and researching case studies at Web sites and in computer magazines. When evaluating hardware solutions for a new information system, the project team considers the overall architecture of the information system based on level of automation, processing methodology, and network technology. Some information systems provide a higher level of automation than others. For instance, a point-of-sale system with a low level of automation might require the checkout clerk to enter credit card numbers from a keypad. At a higher level of automation, a magnetic strip reader automates the process of entering a credit card number. A further level of automation is achieved by using a pressure-sensitive digitizing pad and stylus to collect customer signatures.
An information system can be designed for centralized and distributed processing. Distributed processing in a client/server or peer-to-peer environment is very popular because it provides high levels of processing power at a low cost. Virtually every information system requires a network, so the project team must examine network alternatives, such as LANs, extranets, intranets, and the Internet. Many information systems require a complex mixture of networks, such as a LAN in each branch office connected to a company intranet, with customers accessing selected data using the Internet.
The project team might consider software alternatives, such as whether to construct the system from scratch in a programming language or select a turnkey system.
An information system from scratch is usually costly, but offers the most flexibility for meeting the system requirements. An application development tool is essentially a type of software construction kit containing building blocks that can be assembled into a software product. It includes expert system shells and database management systems.
Commercial software for an information system is usually a series of preprogrammed software modules. It eliminates much of the design work required with programming languages or application development tools. It is available for standard business functions and market businesses and organizations. Although most commercial software has some customization options, in many cases, it cannot be modified to exactly meet every system requirement.
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A turnkey system consists of hardware and commercial software designed to offer a complete information system solution. Like commercial software, a turnkey system must be extensively evaluated to determine whether it can satisfy system requirements.
To determine the best solution, the project team devises a list of criteria for comparing each potential solution. It isnt complicated if the project team uses a decision support worksheet. After the project team selects a solution, the next task is to select the hardware and software. Sometimes the team knows exactly what brand, model, or version of hardware and software are required. At other times, the team has a general understanding, but needs vendor help selecting specific products. RFPs and RFQs help the team collect information for these important decisions. Technical criteria for hardware might include processing speed, reliability, upgradability, maintenance costs, and warranty. Technical criteria for software might include reliability, compatibility, and the availability of patches to fix program errors.
Next step depends on the type of solution selected. If a turnkey solution is selected, the next step might be to get approval to move into the implementation phase of the SDLC. In contrast, if the project team selected a solution that requires custom programming, the teams systems analysts will create a set of application specifications. Many project failures are often referred to as feature creep. Proposed changes should be managed within a formal process that includes written change requests.
Implementation and maintenance
After the plan for an information system is approved, its time to start building it. The implementation phase can include: 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 to be located in an isolated section of storage on the computer system that runs the organizations 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.
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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 organizations 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.
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 systems 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.
Task 8. Match the terms with their definitions.
centralized processing - describes the information system problem and the requirements for the solution.
distributed processing - describes the way the information system software should interact with users, store data, process data, and format reports.
request for proposal (RFP) - in which processing tasks are distributed to servers and workstations.
request for quotation (RFQ) - is a request for a formal price quotation on a list of hardware and software.
application specifications - in which data is processed on a centrally located computer.
Task 9. Choose the ending for each sentence from the two versions given.
1. Distributed processing in a client\server or peer-to-peer environment
a) is very popular because it provides high levels of processing power at a low price.
b) is very popular because it provides the highest levels of processing power at a high price.
2. A series of programmed software modules
a) eliminates much of the design work required with programming languages or application development tools.
b) requires much of the design work with programming languages or application development tools.
3. An application development tool is
a) essentially a type of software construction kit containing building blocks that can be assembled into a software product.
b) a software kit that cant be assembled into a software product.
4. RFPs and RFQs help the team
a) collect information for the important decisions.
b) determine information for the important decisions.
5. Technical criteria for hardware might include
a) processing speed, reliability, upgradability, maintenance cost, and warranty.
b) reliability, compatibility, and the availability of patches to fix program errors.
6. Many project failures are often referred to as features creep
a) because of changes in needs.
b) because old features tend to creep into the development process.
Task 10. Which word does not belong to the group?
a) research, require, study, examine;
b) collect, gather, determine, take;
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c) reliability, compatibility, digitizing, availability;
d) creep,steal, get into, include;
e) card, set, kit, collection;
f) sheave, block, database, pulley.
Task 11. Fill in the missing words choosing from the variants given.
1. The project team should identify potential hardware and software solutions.
a) all b) one from all c) some
2. Distributed processing provides of processing power at a low cost.
a) high levels b) low levels c) intermediate levels
3. Many information systems require a complex mixture of networks, such as a LAN in each branch office a company intranet.
a) separated from b) linked to c) built into
4. An application development tool is essentially a type of software construction kit containing building blocks that can be a software product.
a) included into b) managed by c) put together into
5. A turnkey system consists of hardware and commercial software designed to a complete information system solution.
a) suggest b) control c) design
6. A turnkey system must be extensively evaluated to determine whether it can system requirements.
a) find out b) create c) satisfy
7. The teams systems analysts will create of application specifications.
a) data b) a series c) a criteria
Task 12. Transform the given sentences using the words in brackets without any change in meanings.
1. Distributed processing in a client/server or peer-to-peer environment is very popular because it provides high levels of processing power at a low cost (means).
2. It eliminates much of the design work required with programming languages or application development tools (eliminated).
3. Most commercial software cannot be modified to exactly meet every system requirement (modification).
4. Like commercial software, a turnkey system must be extensively evaluated to determine whether it can satisfy system requirement (asas).
5. At a higher level of automation, a magnetic strip reader automates the process of entering a credit card number (automatically).
6. A further level of automation is achieved by using a pressure-sensitive digitizing pad and stylus to collect customer signatures (collecting).
7. The project team should identify several potential hardware and software solutions by brainstorming and researching case studies at Web sites and in computer magazines (when).
Task 13. Fill in the gaps in the text.
In the ___ phase of the SDLC, the project team identifies solutions, evaluates those solutions, and then selects the best one. It is possible that a ___ system might offer a complete hardware and software solution. The project team can use a___ support worksheet to evaluate solutions based on general, technical, and functional criteria.
After the project team selects a solution, it can then select the specific hardware and software products to build the new information system. The project team might send out a request for ___, asking vendors to recommend a solution and specify hardware and software requirements.
As an alternative, when team members know exactly what hardware and software they need for the solution, they can send out a request for ___, which simply asks for vendor prices. After selecting hardware and software, the team can develop ___ specifications that descried the way the new information system should interact with the user, store data, process data, and format reports.
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Task 14. Speaking. Discuss the following question.
What happens in the design phase?
How does the project team come up with solution?
What hardware alternatives are available?
What software alternatives are available?
How does the team choose the best solution?
How does the project team find the right hardware and software for the new information system?
Whats an RFP and RFQ?
How does the project team evaluate an RFP or RFQ?
What happens after the project team selects a solution?
What is the importance of application specifications?
Task 15. Match the terms with their definitions.
system testing - is the process of modifying a commercial
` application to reflect an organizations needs;
integration testing - ensures that module operates reliably and correctly;
software customization - is performed to ensure that the modules operate together correctly;
acceptance testing - is a place where software testing can occur without disrupting the organizations regular information system, or it might be located on an entirely separate computer system;
unit testing - ensures that all hardware and software components work together correctly;
test area - is designed to verify that the new Information system works as required;
user documentation - is staffed by technical support specialists familiar with the information system software;
procedure handbook - describes a systems features, hardware architecture, and programming;
help desk - describes how to interact with the system to accomplish specific tasks;
system documentation - is a type of user documentation that contains step-by-step instructions for performing specific tasks;
phased conversion - means that the old system is completely deactivated and the new system is immediately activated;
direct conversion - avoids some of the risk of direct conversion because the old system remains in service while some or all of the new system is activated;
pilot conversion - works well with larger information systems that are modularized because the new system is activated one module at a time;
parallel conversion - works well in organizations with several branches that have independent information processing systems because the new information system is activated at one branch at a time.
Task 16. 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. a programmer typically writes. b) 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. |
Task 17. Put the letters in the following words into the correct order.
sienncovor ruvis sinrution shoyubtleroot cascumcriten agerost
Task 18. 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 companys needs.
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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
Task 19. 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 analysts 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) identify errors. h) improve them. |
Task 20. Speaking. Discuss the following questions.
Does a new information system typically require new hardware?
What the next step in the implementation phase?
What is application testing?
What documentation does the project team create during the implementation phase?
How do employees learn how to use the new information system?
How does a business switch from the old information system to the new system?
What happens during the maintenance phase?
How important is system security during this phase?
Who is responsible for system maintenance?
Why do maintenance activities include user support?
Task 21. 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 thephase 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 teams 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 DLTP 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) purchasing and installing software
b) creating applications d) testing applications
