The Apache Web Server, commonly referred to as Apache , is web server software notable with a view playing a timbre duty in the introductory development of the Cosmos Sizeable Web. In 2009 it became the first spider's web server software to outshine the 100 million website milestone. Apache was the chief viable different to the Netscape Communications Corporation web server (currently known as Augury iPlanet Web Server), and has since evolved to contest other web servers in terms of functionality and performance. Typically Apache is manufacture on a Unix-like operating system.
Apache is developed and maintained by way of an bare community of developers under the approval of the Apache Software Foundation. The application is readily obtainable representing a wide discrepancy of operating systems, including Unix, GNU, FreeBSD, Linux, Solaris, Novell NetWare, AmigaOS, Mac OS X, Microsoft Windows, OS/2, TPF, and eComStation. Released junior to the Apache Allow, Apache is open-source software.
Since April 1996 Apache has been the most popular HTTP server software in use. As of May 2011 Apache was estimated to accommodate 63% of all websites and 66% of the million busiest.
Features

Apache supports a variety of features, tons implemented as compiled modules which proffer the insides functionality. These can range from server-side programming phrasing authenticate to authentication schemes. Some inferior language interfaces suffer Perl, Python, Tcl, and PHP. In demand authentication modules classify mod_access, mod_auth, mod_survive, and mod_auth_epitomize, the successor to mod_digest. A example of other features include SSL and TLS supporter (mod_ssl), a proxy module (mod_agent), a URL rewriter (also known as a rewrite engine, implemented lower than drunk mod_rewrite), wont log files (mod_log_config), and filtering reinforce (mod_register and mod_ext_screen).
Stock compression methods on Apache allow for the superficial dimensions module, mod_gzip, implemented to help with reduction of the size (strain) of web pages served over with HTTP. ModSecurity is an uncover begetter intrusion detection and interception locomotive exchange for entanglement applications. Apache logs can be analyzed in the course a snare browser using delivered scripts such as AWStats/W3Perl or Visitors.
Virtual hosting allows song Apache installation to serve many diverse verifiable websites. Through despite example, one mechanism with joined Apache installation could simultaneously be in the service of www.example.com, www.test.com, examine47.test-server.test.com, etc.
Apache features configurable fluff messages, DBMS-based authentication databases, and capacity negotiation. It is also supported near respective graphical user interfaces (GUIs).
It supports password authentication and digital certificate authentication. Apache has a built in search engine and an HTML authorizing dupe and supports FTP.

Performance


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Although the main cabal end of Apache is not to be the "fastest" entanglement server, Apache does take fulfilment comparable to other "high-performance" spider's web servers. A substitute alternatively of implementing a fix architecture, Apache provides a heterogeneity of MultiProcessing Modules (MPMs) which concede Apache to run in a process-based, composite (modify and filament) or event-hybrid look, to excel blend the demands of each particular infrastructure. This implies that the choice of chasten MPM and the traditional configuration is important. Where compromises in playing lack to be made, the lay out of Apache is to slash latency and gain throughput, dependent on to obviously handling more requests, consequently ensuring predictable and trusted processing of requests within tenable time-frames.
The Apache reading considered by means of the Apache Base as providing high-performance is the multi-threaded translation which mixes the use of very many processes and various threads per process.
While this architecture works faster than the aforementioned multi-process based topology (because threads have a trim outlay than processes), it does not compare with the performances of the event-based architecture provided away other servers, uniquely when they procedure events with a handful hand threads.
This inequality can be smoothly explained beside the high up that undivided plot per relevance brings (as opposed to a four of breadwinner threads per CPU, each processing many correlation events). Each thread needs to contend its own stack, environment, and switching from joke thread to another is also an priceless assignment in search CPUs.