System Analysis And Design Analysis Essay Example

is stored.

5. Describe client/server architecture, including fat and thin clients, client/server tiers, and middleware.

Client/server architecture generally refers to systems that divide processing between one or more networked clients and a central server. In a typical client/server system, the client handles the entire user interface, including data entry, data query, and screen presentation logic.

The server stores the data and provides data access and database management functions. Application logic is vided in some manner between the server and the clients. In a client/server interaction, the client submits a request for information from the server, which carries out the operation and responds to the client. Fat client, also called a thick client, design locates all or most of the application processing logic at the client. A thin client design locates all or most of the processing logic at the server. Early client/server designs were called two-tier designs.

In a two-tier design, the user interface resides on the client, all data resides on the server, and the application OIC can run either on the server or on the client, or be divided between the client and the server. In an n-tier system, special software called middleware enables the tiers to communicate and pass data back and forth. Some IT professionals refer to middleware as the glue that holds clients and servers together.

6. Describe the impact of the Internet on system architecture. Include examples.

The Internet has had an enormous impact on system architecture.

The Internet has become more than a communication channel -? many IT observers see it as a fundamentally different environment for system development. In an Internet-based architecture, the entire user interface is

provided by the Web server in the form of HTML coded documents that are interpreted and displayed by the client's browser. It simplifies the process of data transmission and results in lower hardware costs and complexities. The following sections examine Web-based architecture, including: in-house development packaged solutions e-business service providers corporate portals cloud computing web 2.

7. Explain the difference between online processing and batch processing and provide an example of each type.

Online Processing is an online system handles transactions when and where they occur and provides output directly to users. Because it is interactive, online processing avoids delays and allows a constant dialog between the user and the system. Example is Airline reservation system. When an online customer views the reservation system, she can enter the origin, destination, travel dates, and travel times. The system searches a database and responds by displaying available flights, times, and prices.

The customer can make a reservation, enter a name, address, reedit card information, and other required data and the system creates the reservation, assigns a seat, and updates the flight database immediately. While in a batch processing system, data is collected and processed in groups, or batches. Although online processing is used for interactive business systems that require immediate data input and output, batch processing can handle other situations more efficiently. For example, batch processing typically is used for large amounts of data that must be processed on a routine schedule, such as pay checks or credit card ramifications.

8.Explain the difference between a LANA and a WAN, define the term topology, and draw a sketch of each wired and wireless network model. Also describe four

IEEE 802. 11 amendments.

LANA is a computer network that connects computers in small areas such as home, office, school, corporation, etc. Using a network media. It is useful for sharing resources such as printers, files, games, etc. A LANA network includes a couple of computer systems connected to each other, with one system connected to a router, modem or an outlet for internet access. The LANA network is lilt using inexpensive technologies such as Ethernet cables, network adapters and hubs.

WAN is a network that covers a broad area using private or public network transports. The best example of WAN would be the Internet, which can help connect anyone from any area of the world. Many businesses and government use WAN in order to conduct business from anywhere in the world. Wants are also responsible largely for businesses that happen across the world (I. E. A company in UK does business with a company in China). The basic definition of WAN includes a network that can span regions, countries, or even the world. Outwork topology The way a network is configured.

LANA and WAN networks typically are arranged in one off our patterns: hierarchical, bus, star, and ring. The IEEE 802. 11 amendments. Standard Introduced Max Speed Approximate Range Compatibility 802. Bib 1999 11 Mbps 100-effete Early 802. 11 version 802. AAA 1999 54 Mbps 50-100 feet Incompatible with 802. Bib and 802. 1 log 802. 11 g 2003 54 Mbps 50-100 feet compatible with 802. Bib 802. 1 In 2009-2010 200+ Mbps 150-300 feet compatible with all 802. 11

9. Explain the differences between the BBS, SEES, and SIS wireless topologies. Which is

rarely used in business? To what kind of network do the 802. 6 standards apply?

The Basic Service Set (BBS), also called the infrastructure mode, a configuration where a central wireless device called an access point is used to serve all wireless clients. The access point is similar to a hub in the LANA star topology, except it provides network services to wireless clients instead of wired clients. Because access points use a single communications medium, the air they broadcast all traffic to all clients, just as a hub would do in a wired network. Typically, the access point itself is unconnected to a wired network, so wireless clients can access the wired network.

Extended Service Set (SEES), is made up of two or more Basic Service Set networks. Thus, using an SEES topology, wireless access can be expanded over a wide area. Each access point provides wireless services over a limited range. As a client moves away from one access point and closer to another, a process called roaming automatically allows the client to associate with the stronger access point, allowing for undisrupted service. Independent Service Set (SIS), also called peer-topper mode, no access point is used. Instead, wireless clients connect to each other directly.

Most business Walla use access points to provide wireless services, and do not utilize the Independent Service Set. However, SIS is well-suited to situations requiring quick data transfer among clients. IEEE is working on 802. 16 standards, which are broadband wireless communications protocols for MANS (metropolitan area networks). These specifications, which IEEE calls Wirelessly, or Wimp, are expected to enable wireless multimedia applications with a range of up to

30 miles. 9. List the sections of a system design specification, and describe the contents. A typical system design specification typically includes the following sections.

1. Executive Summary. The management summary provides a brief overview of the project for company managers and executives. It outlines the development efforts to date, provides a current status report, summarizes current project costs and costs for the remaining phases, reviews the overall benefits of the new system, presents the systems development phase schedule, and highlights any issues that management will need to address.

2. System Components. This section contains the complete design for the new yester, including the user interface, outputs, inputs, files, databases, and network specifications.

You should include source documents, report and screen layouts, Doffs, and all other relevant documentation. You also should include the requirements for all support processing, such as backup and recovery, start-up processing, and file retention. If the purchase of a software package is part of the strategy, you must include any interface information required between the package and the system you are developing. If you use a CASE design tool, you can print sign diagrams and most other documentation directly from the tool.