A network is a group of computers connected together using cables, satellites or the telephone system.
The fileserver stores all the files and controls the flow of data to and from each workstation.
Local Area Networks
- Computers linked together that are in the same building or room, e.g. the school network.
- Computers linked together using cables.
Wide Area Networks
- Computers linked together across a country, continent or even the word, e.g. the Internet.
- Computers linked together using the telephone system and a modem or satellite.
Why use a network?
- Computer users can use any computer on the network
- Expensive resources, such as printers and scanners, can be used by all users of the network.
- Expensive software can be also be shared.
- Users can communicate easily.
Benefits of a Wide Area Network (WAN) to the Electronic Office
- The vast ease with which a company or individual can get access to the World Wide Web means it is getting a very popular method of communication. The Internet and email services are now being provided with just the cost of a local telephone call. Firms can communicate with their clients around the world for just the price of a local call.
- Communication is quick and inexpensive, especially to far regions.
- A modem is needed to communicate over the Internet. A modem acts like an interpreter that translates digital signals given out by the computer to audio signals that are understood by the telephone system.
Drawbacks of a Wide Area Network (WAN) to the Electronic Office
- Staff will need to be trained into using the WAN. This includes:
- Accessing information on the Internet,
- Looking for information on the Internet,
- Sending and receiving email.
- Sending files as attachments to email.
- Staff will therefore have to be trained, costing time and money.
- Steps will need to be taken to ensure that the system is safe and regularly backed up. (If a computer is connected to a WAN there is a risk that an unauthorised user may access the system.)
Setting Up a Network
Computer networks are expensive to install, largely due to the vast amount of cabling required. Staff also need to be trained to use the network. A network manager or systems administrator also has to be trained to look after the network, for example changing the tape in backing-up files etc. or adding new users to the network.
Components of a Network.
|
Component |
Purpose |
|
The File Server |
The file server is the 'engine' of the network. The software available to each user and the centrally stored files such as customer files are stored on the file server. Without the file server the network cannot operate. |
|
The work stations/terminals/ nodes |
The work stations are the terminals or 'computers' that each employee works at. It normally consists of a monitor, keyboard, hard disk and mouse. Several computers or work stations may have other peripherals such as scanners, digital cameras or modems. |
|
The Printer(s) |
Normally several printers will be located at various parts of the network, such as two to three in each room or department. |
|
Fibre optic cables. |
Used to transmit the flow of data to and from the file server to each work station. |
|
The Tape Streamer |
The purpose of the tape streamer is to create a back-up file on tape of all the files stored in the network. Backing-up normally takes place during the night whenever the network is not being used. The systems administrator can set the network up so that this is done automatically. The tape is then changed in the morning. |
FACTORS TO CONSIDER WHEN SITING A NETWORK
The following points should be considered when setting up the network:
- Where will the network's main server be stored. This should be in a safe place, usually a separate room not used by staff and secure. This room should be locked and accessed only by the system administrator.
- The file server should be as close to the work stations as possible. This reduces the amount of fibre optic cables used, therefore reducing cost.
- The work stations should be well spaced out so that each network user can access the work stations with ease and whenever they require.
- The network should be situated where access to an ISDN line or telephone line is possible should the network be connected to a Wide Area Network (WAN).
Is a Computer Network Advantageous to the Electronic Office
- Printers, scanners, software packages can be shared, thus reducing cost greatly.
- Files required by all users, e.g. customer files, need only to be stored once. Updating files is only required once.
- Users can access their work from any work station.
- Users can easily and quickly communicate with each other.
