Network Hardware Revision

Network Hardware Revision

1. A network is created when more than one device is connected together. A network can be a small collection of computers connected within a building (eg a school, business or home) or it can be a wide collection of computers connected around the world.

2. Data packets The main purpose of networking is to share data between computers. A file has to be broken up into small chunks of data known as data packets in order to be transmitted over a network. The data is then re-built once it reaches the destination computer. Networking hardware is required to connect computers and manage how data packets are communicated. Protocols are used to control how data is transmitted across networks.

3. Advantages Communication – it is easy (and often free) to communicate using email, text messages, voice calls and video calls. Roaming – if information is stored on a network, it means users are not fixed to one place. They can use computers anywhere in the world to access their information. Sharing information – it is easy to share files and information over a network. Music and video files, for instance, can be stored on one device and shared across many computers, so every computer does not need to fill the hard drive with files. Sharing resources – it is easy to share resources such as printers. Twenty computers in a room could share one printer over a network. Sharing software – it is possible to stream software using web applications. This avoids needing to download and store the whole software file.

4. Disadvantages Dependence – users relying on a network might be stuck without access to it. Hacking - criminal hackers attempt to break into networks in order to steal personal information and banking details. This wouldn't be possible on a stand-alone computer without physically getting into the room, but with a network it is easier to gain access. Hardware – routers, network cards and other network hardware is required to set up a network. At home, it is quite easy to set up a wireless network without much technical expertise. However, a complicated network in a school or an office would require professional expertise. Viruses - networks make it easier to share viruses and other malware. They can quickly spread and damage files on many computers via a network.

5. LANs and WANs A network can be anything from two computers connected together, to millions of computers connected on the internet. There are many different types of networks such as LAN, WAN, VPN, WPAN and PAN.

6. A LAN (local area network) is a network of computers within the same building, such as a school, home or business. A LAN is not necessarily connected to the internet.

7. WAN A WAN (wide area network) is created when LANs are connected. This requires media such as broadband cables, and can connect up organisations based in different geographical places. The internet is a WAN.

8. VPN A VPN (virtual private network) is usually hosted securely on another network, such as the internet, to provide connectivity. VPNs are often used when working on secure information held by a company or school.

   • WPAN A WPAN (wireless personal area network) allows an individual to connect devices (such as a smartphone) to a desktop machine, or to form a Bluetooth connection with devices in a car. A wired personal network is called a PAN (personal area network).

9. Topologies There are different ways of setting up a LAN, each with different benefits in terms of network speed and cost. Three of the main topologies include bus, star and ring.

   • Bus network In a bus network all the workstations, servers and printers are joined to one cable - 'the bus'. At each end of the cable a terminator is fitted to stop signals reflecting back down the bus.
     • Advantages easy to install cheap to install - it does not require much cabling Disadvantages if the main cable fails or gets damaged, the whole network will fail as more workstations are connected, the performance of the network will become slower because of data collisions every workstation on the network 'sees' all of the data on the network, which can be a security risk
       • Ring network In a ring network, each device (eg workstation, server, printer) is connected in a ring so each one is connected to two other devices. Each data packet on the network travels in one direction. Each device receives each packet in turn until the destination device receives it.

Imágenes y archivos del mapa