Proxy server is a server application which exchanges the communication between internet and hosts in the local area network. Classical proxy servers exchange services http, https, ftp, gopher and similar. It is required to exchange other protocols by the socks protocol or by other dedicated proxy servers. Linux enables both means of communication exchange. The classical proxy server served by squid suite is enhanced by cache, which lighten the network load. The squid suite enables to authenticate users and to control the access of them to resources by various criteria. It also enables to control the bandwidth assigned to users or groups. Naturally, it logs every communication.

The proxy server could exchange internet services for users authorised by IP addresses of their workstations. This IP address could identify the originating workstation.

Proxy server could exchange internet services for authorised users authenticated by login and password. User can use the internet exchange for a specified time period after password input.

It is often needed to assignd bandwidth separately for users or groups of users by priority. Especially when relatively slow internet connection is in use. It is possible to create bandwidth limits for users or group users in squid proxy suite.