There are two types of networks LAN (local area network). LAN networks on the other hand usually only cover small areas of one to several KM. Although this may seem like a large area it is still considered small or local. WAN (wide area network) networks are characterized by the distance the transverse and the fact that they will always be attached to a common carrier of some type, either the good old AT&T or one of the more that 100 common carriers available in any metropolitan area.
These are the networks that you find in schools and offices for example our school network, which is a LAN network covers a large area but is contained on one site. There may be many computers on the network and even several servers but they are always on the one site. The servers serve up information and programs as people working at the network stations request them. It is common to share printers and other output devices, so that saves the organisation money. The software used on the network is also shared.
An organisation has to pay a network license fee for the software but this still works out cheaper than buying software for each individual machine. It also allows email, which is the way that much day-to-day communication takes place. But it’s not all good. The organisation has to pay technical staff to maintain the network. User accounts need to be added and deleted as people join and leave an organisation. Because users’ data is stored on the hard drives in the servers these need to be backed up regularly or there would be a public outcry if it were lost. Networks fail occasionally and then no one in the organisation can use the computers.
As more users log onto the network, the servers have to share their time among them and the system may slow down. Users forget their passwords and can’t log on, which causes additional work for the Network Manager. Or, because each user is allocated a specific amount of space on the hard drive, they exceed it and moan for more. And, users tend to get up to all kinds of naughty tricks like hacking into other users’ areas, downloading or installing software that they shouldn’t, stealing peripherals, clogging the system up with silly emails, forgetting to log off and so on.
Security can become a major headache. Networks are better than stand alones because: – Printers can be shared: individual stations do not need their own printer. When they print, the data is stored in a queue on the file sever. Programs can be shared: software packages are stored on the file server and downloaded to work stations as requested. Data can be shared: database files stored in the file server are available to users around the network; data from CD-ROMs can also be shared. Users can communicate with others on the network, sending messages and sharing files.