Squid is a high-performance proxy caching server and web cache daemon. It supports FTP, gopher and HTTP data objects.
Squid has a wide variety of uses, from speeding up a web server by caching repeated requests, caching web, DNS and other computer network lookups for a group of people sharing network resources; to aiding security by filtering traffic.
Squid consists of a main server program squid, a Domain Name System lookup program dnsserver, some optional programs for rewriting requests and performing authentication, together with some management and client tools.
Squid offers a rich access control, authorization and logging environment to develop web proxy and content serving applications.
- Web proxy:
- Caching to reduce access time and bandwidth use.
- Keeps meta data and especially hot objects cached in RAM.
- Caches DNS lookups.
- Supports non-blocking DNS lookups.
- Implements negative checking of failed requests.
- Squid caches can be arranged in a hierarchy or mesh for additional bandwidth savings.
- Enforce site-usage policies with extensive access controls.
- Anonymize connections, such as disabling or changing specific header fields in a client’s HTTP request.
- Reverse proxy.
- Media-range limitations.
- Supports SSL.
- Support for IPv6.
- Error Page Localization – error pages presented by Squid may now be localized per-request to match the visitors local preferred language.
- Connection Pinning (for NTLM Auth Passthrough) – a workaround which permits Web servers to use Microsoft NTLM Authentication instead of HTTP standard authentication through a web proxy.
- Quality of Service (QoS) Flow support:
- Select a TOS/Diffserv value to mark local hits.
- Select a TOS/Diffserv value to mark peer hits.
- Selectively mark only sibling or parent requests.
- Allows any HTTP response towards clients to have the TOS value of the response coming from the remote server preserved.
- Mask certain bits in the TOS received from the remote server, before copying the value to the TOS send towards clients.
- SSL Bump (for HTTPS Filtering and Adaptation) – Squid-in-the-middle decryption and encryption of CONNECT tunneled SSL traffic, using configurable client- and server-side certificates.
- eCAP Adaptation Module support.
- ICAP Bypass and Retry enhancements – ICAP is now extended with full bypass and dynamic chain routing to handle multiple adaptation services.
- ICY streaming protocol support – commonly known as SHOUTcast multimedia streams.
- Dynamic SSL Certificate Generation.
- Support for the Internet Content Adaptation Protocol (ICAP).
- Full request logging.
|New to Linux? Read our Linux for Starters series. We start right at the basics and teach you everything you need to know to get started with Linux.|
|The largest compilation of the best free and open source software in the universe. Each article is supplied with a legendary ratings chart helping you to make informed decisions.|
|Hundreds of in-depth reviews offering our unbiased and expert opinion on software. We offer helpful and impartial information.|
|Replace proprietary software with open source alternatives: Google, Microsoft, Apple, Adobe, IBM, Autodesk, Oracle, Atlassian, Corel, Cisco, Intuit, and SAS.|
|Getting Started with Docker helps you master Docker, a set of platform as a service products that delivers software in packages called containers.|
|Essential Linux system tools focuses on small, indispensable utilities, useful for system administrators as well as regular users.|
|Linux utilities to maximise your productivity. Small, indispensable tools, useful for anyone running a Linux machine.|
|Home computers became commonplace in the 1980s. Emulate home computers including the Commodore 64, Amiga, Atari ST, ZX81, Amstrad CPC, and ZX Spectrum.|
|Now and Then examines how promising open source software fared over the years. It can be a bumpy ride.|
|Linux at Home looks at a range of home activities where Linux can play its part, making the most of our time at home, keeping active and engaged.|
|Linux Candy reveals the lighter side of Linux. Have some fun and escape from the daily drudgery.|
|Best Free Android Apps. We showcase free Android apps that are definitely worth downloading. There's a strict eligibility criteria for inclusion in this series.|
|These best free books accelerate your learning of every programming language. Learn a new language today!|
|These free tutorials offer the perfect tonic to our free programming books series.|
|Stars and Stripes is an occasional series looking at the impact of Linux in the USA.|