About Squid proxy servers

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Squid is a proxy caching server which provides proxy and cache services for Hyper Text Transport Protocol (HTTP), File Transfer Protocol (FTP), and other popular network protocols.

It acts as an intermediary between web servers and clients. When a client sends a request for content, Squid fetches the content from the web server and creates a local copy. Then, if a request is made again, it shows the local, cached copy instead of making another request to the web server. In this way, performance is improved and network bandwidth is optimised. It can also filter web traffic, helping to improve security.

Features

The Squid proxy cache server scales from the branch office to enterprise level networks. It provides extensive, granular access controls, and monitoring of critical parameters via the Simple Network Management Protocol (SNMP).

When selecting a computer system for use as a dedicated Squid caching proxy server, it is helpful to configure it with a large amount of physical memory as Squid maintains an in-memory cache for increased performance.

Caching

Squid can implement caching and proxying of Secure Sockets Layer (SSL) requests and caching of Domain Name Server (DNS) lookups, and perform transparent caching. Squid also supports a wide variety of caching protocols, such as Internet Cache Protocol (ICP), the Hyper Text Caching Protocol (HTCP), the Cache Array Routing Protocol (CARP), and the Web Cache Coordination Protocol (WCCP).

If you would like to know how to install and configure your own Squid server, refer to our installation guide.

Further reading

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