Network: Components and use

What is a network? What is used for it?


A network is a connection of computers connected to other components. They are used in local areas (LAN) and wide areas (WAN).


A network server is a computer designed to process requests and deliver data to other (client) computers over a local network or the Internet. Network servers typically are configured with additional processing, memory and storage capacity to handle the load of servicing clients. Common types of network servers include:
  • Web Servers
  • Proxy Servers
  • FTP servers
  • Online Game Servers


A client application, or client for short, is a program that submits requests (SQL queries) to the server and gets results back from the server.

A client program is separate from the server program. In many cases, the client is also running on a separate computer. Using shared memory access or linked library access, you can link the client's code directly to the server's code so that both run as a single process.

Advantages of Networks


  • Easy to implement and extend
  • Well suited for temporary networks (quick setup)
  • Initially less expensive than other topologies
  • Cheap


  • Data is quickly transferred without a ‘bottle neck’. (very fast, all data traffic is in the same direction)
  • The transmission of data is relatively simple as packets travel in one direction only.
  • Adding additional nodes has very little impact on bandwidth
  • It prevents network collisions because of the media access method or architecture required.


  • Good performance
  • easy to set up and to expand. Any non-centralised failure will have very little effect on the network, whereas on a ring network it would all fail with one fault

Disadvantages of Networks


  • Difficult to administer/troubleshoot.
  • Limited cable length and number of stations.
  • If there is a problem with the cable, the entire network goes down.
  • Maintenance costs may be higher in the long run.
  • Performance degrades as additional computers are added or on heavy traffic.
  • Low security (all computers on the bus can see all data transmissions).
  • One virus in the network will affect all of them (but not as badly as a star or ring network).
  • Proper termination is required.(loop must be in closed path).
  • If one node fails, the whole network will shut down.
  • If many computers are attached, the amount of data flowing causes the network to slow down.


  • Data packets must pass through every computer between the sender and recipient therefore this makes it slower.
  • If any of the nodes fail then the ring is broken and data cannot be transmitted successfully.
  • It is difficult to troubleshoot the ring.
  • Because all stations are wired together, to add a station you must shut down the network temporarily.
  • In order for all computers to communicate with each other, all computers must be turned on.
  • Total dependence upon the one cable


  • Expensive to install
  • Extra hardware required

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LAN stands for local are network. It supplies networking capability to a group of computers in close proximity to each other such as in an office building, a school, or a home. A LAN is useful for sharing resources like files, printers, games or other applications. A LAN in turn often connects to other Local Area Networks, and to the Internet or other WAN.
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A WAN spans a large geographic area, such as a state, province or country. WANs often connect multiple smaller networks, such as local area networks (LANs) or metro area networks (MANs). The world's most popular WAN is the Internet.

Advantages of Area Networks


  • Easy to share devices (printers, scanners, external drives)
  • Easy to share data (homework, pictures..)
  • Build a complex enough one and you may get enough experience to get a new job.
  • Cost of LAN Setup is low.


  • Covers a large geographical area so long distance businesses can connect on the one network.

  • Shares software and resources with connecting workstations

  • Messages can be sent very quickly to anyone else on the network. These messages can have pictures, sounds, or data included with them (called attachments).

  • Expensive things (such as printers or phone lines to the internet) can be shared by all the computers on the network without having to buy a different peripheral for each computer.

  • Everyone on the network can use the same data. This avoids problems where some users may have older information than others.

  • Share information/files over a larger area

  • Large network cover

  • Disadvantages of Area Networks

    • LAN
    • Power - a good LAN is required to be on all the times.
    • Security - each computer and device become another point of entry for undesirables.
    • Upkeep - when things go wrong or the software gets updated.
    • Frustration if having a problem setting up.
    • A lot of times a network shares one Internet connection - if all computers running at once, can reduce speed for each.
    • Area covered is limited.
    • WAN
    • Are expensive and generally slow
    • Need a good firewall to restrict outsiders from entering and disrupting the network
    • Setting up a network can be an expensive and complicated experience. The bigger the network the more expensive it is.
    • Security is a real issue when many different people have the ability to use information from other computers. Protection against hackers and viruses adds more complexity and expense.
    • Once set up, maintaining a network is a full-time job which requires network supervisors and technicians to be employed.
    • Information may not meet local needs or interests
    • Vulnerable to hackers or other outside threats