A server is a computer that provides the data, software and hardware resources (like printers) that are shared on the LAN. A LAN can have more than one server. Each server has a unique name on the network and all LAN users identify the server by its name.
Dedicated Server
A server that functions only as a storage area for data and software and allows access to hardware resources is called a dedicated server. Dedicated servers need to be powerful computers capable of handling the huge workloads demanded of them.
Non-dedicated Server
In many LANs, the server is just another workstation. Thus, there is a user working on the computer and using it as a workstation, but part of the computer also doubles up as a server. Such a server is called a non-dedicated server (since it is not completely dedicated, to serving). Such a server is typically used by small LAN installations that have a few workstations. Such LANs do not require a dedicated server since resource sharing amongst a few workstations is on a proportionately smaller scale.
Other Types of Servers
In large LAN installations, which have hundreds of workstations sharing resources, a single computer is often not sufficient to function as a server. Consequently, the LAN may have several servers that allow workstations to share specific resources. Some of the servers have been discussed hereunder.
- File Server: A file server stores files that LAN workstations can access. It also decides on the rights and restrictions that the users need to have while accessing files on the LAN. For example, if an employee in the marketing department wants to access classified files of the accounts department, he or she would not be able to do that, unless the appropriate permissions are granted. The file server also allows LAN users to store files on their own hard disks. The file server regulates the amount of space allowed for each user.
- Printer Server: A printer server takes care of the printing requirements of a number of workstations (remember one of the main advantages of a LAN is that it helps the workstations share hardware resources like printers). In a LAN with a large number of workstations, several users could give requests for printing in intervals of just a few minutes. The printer server typically stores the files to be printed on its disk, and then executes these requests (i.e. prints these files) on a first-in-first-out basis.
- Modem Server: A modem server allows LAN users to use a modem to transmit long distance messages. Typically, in an organization, only a few users would need to use the modem. A single modem server attached to one or two modems would serve the purpose.