• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  • Level: GCSE
  • Subject: ICT
  • Word count: 1380

ICT Unit 4 Networks Notes - LAN and WAN networks

Extracts from this document...

Introduction

Unit 4 Computer Networks 1. What is a network A network is a system that sends and receives data and messages enabling two or more computers to communicate with each other Networks typically allow computers to share files, share printers and send messages to each other The typical hardware devices that from part of a network are: * Personal computers used as terminals * One or more central processing units acting as dedicated file servers or print servers * Disk drives * Scanners * Printers 2. Types of network There are two types of network: LAN - Local Area Network A network contained within one building or site called a Local Area Network (LAN). WAN - Wide Area Network A network that spans several sites across a city, country or even the world is called Wide Area Network (WAN). a) Local Area Network (LAN) A LAN is a Local Area Network covering a small area such as one building e.g. in a scholl or college. Within a LAN, computers and other hardware devices are connected to the file server. This allows the computers to share resources. b) Wide Area Network (WAN) A WAN is a Wide Area Network covering a large geographical area. A wide area network is not confined to one building. The hardware that forms part of the network can spread around the world. ...read more.

Middle

having to be re-sent * Adding additional devices has very little impact on data transfer speed * Relatively cheap to install and expand Disadvantages: * The least reliable topology as there is total dependence upon the one cable. If it fails, all the workstations will be affected * The hardest topology to troubleshoot if there is a cable failure * Because all stations are wired together, to add a station you must shut down all the network temporarily * In order for all computers to communicate with each other, all the computers must be turned on c) Star topology In a star network all the computers are connected separately to the hub or server Advantages: * The most reliable because cable failure does not affect other users * Good performance because there is a direct path from the central controller to each terminal * Easy to set up and expand Disadvantages: * Uses a lot of cable which is expensive to install * Extra hardware required such as hubs and/or switches * As the central machine controls the whole system, the whole system will be affected if it breaks down 5. Formation of a network A network is not just a number of computers connected by cables. The components found in a typical network are: a) ...read more.

Conclusion

It passes messages from one segment to the other. For example, if there was a LAN segment in two different buildings, the bridge transfers the messages from one building to the other. f) Wi-Fi Wi-Fi is used in a wireless LAN. It allows the wireless exchange of data over a distance of 10 to 20 metres and at a data transfer rate of 50 to 450 Mbps (megabits per second). It is useful for laptops, game consoles, televisions, printers and digital cameras. g) Bluetooth Bluetooth is used for wireless connections over a short distance, e.g. only a few metres. It does not use much power, and the rate of data transfer is low (between one and tree Mbps). It is typically used to connect battery-powered devices, e.g. ear-pieces, mobile phones or MP3 players, with computers. h) Proxy servers Proxy servers are most frequently used on the Internet to improve the performance of Web services to multiple clients. For example, in a school or large office, all client browsers can be connected to a proxy server. The proxy server requests pages from the desired Web sites and returns them to the client. However, it remembers or caches these pages so that if a different client requests the same page, it will be returns immediately from its cache rather than requesting it again from the original Web site. ?? ?? ?? ?? Monday, 19 January 2009 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Hardware section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Hardware essays

  1. Computer Hardware, uses, advantages and disadvantages.

    The stream passes over the entire monitor at a rate of 50 to 100 times per second to create the continuous interactive image that we see. (http://www.ehow.com/how-does_4572304_computer-monitor-work.html) (04/12/2010) The advantages of using CRT monitors are: 1: You can buy it relatively cheap.

  2. Ict - Unit 2B

    Input Devices: Mouse: The Marketing department uses the mouse regularly to fulfil there most simple and efficient needs when using a computer, such as when browsing the computer or reaching to other destinations where no keyboard shortcuts are available. Apart from the most basic uses of the mouse the Marketing

  1. Hardware Choices and Operating System.

    This can save you some space in front of your computer. It is more expensive than a wired keyboard. Software Software is written programs or rules that refer to the operation of a computer system that are stored in read or write memory.

  2. Choosing hardware and input devices.

    For this it has different functions like formatting text into different styles. The wizard makes it easier for new beginners to use. The wizards appear too much which is distractible. The main difference is that I would be able to create and edit text, reports, web ages and email messages easier and much more accurate.

  1. GCSE ICT - Imput devices.

    In the library staff use a barcode scanner located at the issue desk to in libraries to scan the barcodes on stock and members cards. Before libraries used barcode scanners had to type the code in by keyboard, this took time and often mistakes were made when typing in codes, resulting in members and stock details being inaccurate.

  2. Choosing the best harware for my system.

    is the most advanced scanner and it produces the best quality of work. Another advantage is that the flatbed scanner is very good for scanning from magazines or lots of pages to scroll. More expensive than a other scanner. Fragile parts can be measured and there is no worry for offset.

  1. Unit 14 Mobile communication technology

    Bluetooth Bluetooth is used to connect to different devices without having to be in line of sight of each other and are useful for hands free kits like while driving, transferring data or even playing multiplayer games with nearby devices.

  2. ICT Revision notes

    Gigabyte (GB) 5. Terabyte (TB) Input devices ? hardware used to input data Examples: Keyboard ? used to enter letters and numbers, and used for shortcuts. Mouse ? used to point and click. Output devices ? hardware that is used to output data Examples: speaker ? if you need

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work