The characteristics of networks

A network consists of two or more computer systems that are connected together to allow them to share resources and exchange information. There are many advantages and disadvantages of using a computer network over a stand-alone computer.

Advantages

• Share hardware resources, such as printers, scanners and back up facilities.

• Share software that is licensed for use over a network.

• Share data/files that are stored centrally on a server.

• Easier for internal communication/can send email.

• Easier to monitor network activity of user accounts.

• Centrally controlled security.

Disadvantages

• Security problems – if a virus is introduced to a single computer it can spread throughout the entire network.

• Hackers can gain access to data more easily with machines being connected to the Internet.

• If the server is down, all workstations on the network are affected.

• Initial cost of servers, communication devices etc can be expensive.

There are two main types of network, namely a Local Area Network (LAN) and a Wide Area Network (WAN).

A LAN is a network in which the computer systems are all located relatively close to each other, for example in the same building or on the same site, such as a school.

A WAN is a network in which the computer systems are all located relatively far from each other, for example in different buildings all over the country or in different countries altogether. The Internet is an example of a WAN. Note that many LANs could be linked using a WAN.

Computer networks use agreed upon protocols to communicate, i.e. common methods of sending data and consistent data formats. Without these protocols the individual computer systems would not be able to communicate with each other.