What is Squid?

Squid is a fully-featured HTTP/1.0 proxy which is almost (but not quite - we're getting there!) HTTP/1.1 compliant. Squid offers a rich access control, authorization and logging environment to develop web proxy and content serving applications.

Where did Squid come from?

Squid is based on the Harvest Cache Daemon developed in the early 1990's. It was one of two forks from the codebase after the Harvest project ran to completion. (The other fork being what became Netapp's Netcache.)

The Squid project was funded by an NSF grant (NCR-9796082) which covered research into caching technologies. The ircache funding ran out a few years later and the Squid project continued through volunteer donations and the occasional commercial investment.

Squid is currently being developed by a handful of individuals donating their time and effort to building current and next generation content caching and delivery technologies. An ever-growing number of companies use Squid to save on their internet web traffic, improve performance, deliver faster browsing to their end-clients and provide static, dynamic and streaming content to millions of internet users worldwide.

Squid: Optimising Web Delivery

Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages. Squid has extensive access controls and makes a great server accelerator. It runs on most available operating systems, including Windows and is licensed under the GNU GPL.

Making the most of your Internet Connection

Squid is used by hundreds of Internet Providers world-wide to provide their users with the best possible web access. Squid optimises the data flow between client and server to improve performance and caches frequently-used content to save bandwidth. Squid can also route content requests to servers in a wide variety of ways to build cache server hierarchies which optimise network throughput.

Website Content Acceleration and Distribution

Thousands of web-sites around the Internet use Squid to drastically increase their content delivery. Squid can reduce your server load and improve delivery speeds to clients. Squid can also be used to deliver content from around the world - copying only the content being used, rather than inefficiently copying everything. Finally, Squid's advanced content routing configuration allows you to build content clusters to route and load balance requests via a variety of web servers.

" [The Squid systems] are currently running at a hit-rate of approximately 75%, effectively quadrupling the capacity of the Apache servers behind them. This is particularly noticeable when a large surge of traffic arrives directed to a particular page via a web link from another site, as the caching efficiency for that page will be nearly 100%. " - Wikimedia Deployment Information.

Want to learn more?

The Squid project provides a number of resources to assist users design, implement and support Squid installations. Please browse the Documentation and Support sections for more information.