Task 2. Indicate the paragraph where the following ideas are found in the text.
These plans are developed during the planning phase.
You can determine the system requirements by this way.
A list of requirements for a new system should be produced at this phase.
Several phases are required for information process.
A plan is inseparable part of an information system.
There are plenty of tools for diagramming and specifying the current system.
Task 3. Match up the words that are opposite in the meaning.
succeed essential
permission computerized
updated fail
manual destroy
create out out of date
obsolete ban
Task 4. Fill in the blanks choosing from the variants given.
1. Project management software is an effective tool for … and scheduling.
a) planning b) maintenance c) analysis d) development
2. “A project team” is a group of people who are assigned to analyze and … an information system.
a) maintain b) develop c) implement d) test
3. Users and analysts work together to identify problems and look for solution in a development process called … application design.
a) co-operative b) united c) joint d) mutual
4. A modified waterfall SDLC allows to … between SDLC phases
a) overlap b) break c) skip d) stretch
5. A System Requirements Report describes the … for a new information system.
a) innovations b) ideas c) objectives d) goals
6. It is difficult to complete the design phase until system … have a chance to work with software tools that are purchased in the implementation phase.
a) analysts b) developers c) builders d) administrators
Task 5. Make three-word combinations using the words in columns and them fill in the gaps in the following sentences.
A: information B: source C: source
joint requirements software
project application plan
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open system report
system management project
project development software
… describes the objectives for an information system.
… is developed during the planning phase.
… must be reviewed and approved by the management.
You can use … for planning and scheduling.
OpenWork Bench and Microsoft Project are …, aren’t they?
… is based on the idea that the best information systems are designed when end-users and system analysts work together as equal partners.
Task 6. Fill in the gaps in the text.
The process of planning and building an information system is referred to as systems ___.The development process is supervised by an organization’s Information Systems (IS) department, but the ___ team includes members from other departments as well. System development follows some type of system development ___ cycle (SDLC), which consists of several phases. In the ___ SDLC one phase of the SDLC must be completed before the next phase begins. A project begins with a ___ phase in which a member of the IS department creates a Project Development Plan. The project team then proceeds to the ___ phase, with the goal of producing a list of requirements for a new or revised information system.
Task 7. Speaking. Discuss the following questions .
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.
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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 isn’t 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 team’s 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, it’s 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.
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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 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.
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.
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