Apache HTTP Server

According to The Apache Software Foundation, its name was chosen "from respect for the various Native American nations collectively referred to as Apache, well-known for their superior skills in warfare strategy and their inexhaustible endurance". This was in a context in which it seemed that the open internet—based on free exchange of open source code—appeared to be soon subjected to a kind of conquer by proprietary software vendor Microsoft; Apache co-creator Brian Behlendorf—originator of the name—saw his effort somewhat parallel that of Geronimo, Chief of the last of the free Apache peoples. But it conceded that the name "also makes a cute pun on 'a patchy web server'—a server made from a series of patches". Despite the Foundation's current claim that the name was chosen out of respect for Native Americans, previous statements, such as the project's official documentation in 1995, say that the name was instead based on a pun. This documentation did not mention Native American tribes in the context of the name: In addition, Behlendorf made no reference to Native American tribes when he talked about the origins of the name in a 2000 interview, where he stated that it was not a pun, but was instead chosen to be aggressive-sounding: In January 2023, the US-based non-profit Natives in Tech accused the Apache Software Foundation of cultural appropriation and urged them to change the foundation's name, and consequently also the names of the software projects it hosts. The Foundation did not change the name. When Apache is running under Unix, its process name is , which is short for "HTTP daemon". ==Feature overview==

Apache supports a variety of features, many implemented as compiled modules which extend the core functionality. These can range from authentication schemes to supporting server-side programming languages such as Perl, Python, Tcl and PHP. Popular authentication modules include mod_access, mod_auth, mod_digest, and mod_auth_digest, the successor to mod_digest. A sample of other features include Secure Sockets Layer and Transport Layer Security support (mod_ssl), a proxy module (mod_proxy), a URL rewriting module (mod_rewrite), custom log files (mod_log_config), and filtering support (mod_include and mod_ext_filter). Popular compression methods on Apache include the external extension module, mod_gzip, implemented to help with reduction of the size (weight) of web pages served over HTTP. ModSecurity is an open source intrusion detection and prevention engine for Web applications. Apache logs can be analyzed through a Web browser using free scripts, such as AWStats/W3Perl or Visitors. Virtual hosting allows one Apache installation to serve many different websites. For example, one computer with one Apache installation could simultaneously serve example.com, example.org, test47.test-server.example.edu, etc. Apache features configurable error messages, DBMS-based authentication databases, content negotiation and supports several graphical user interfaces (GUIs). It supports password authentication and digital certificate authentication. Because the source code is freely available, anyone can adapt the server for specific needs, and there is a large public library of Apache add-ons. A more detailed list of features is provided below: • Loadable Dynamic Modules • Multiple Request Processing modes (MPMs) including Event-based/Async, Threaded and Prefork. • Highly scalable (easily handles more than 10,000 simultaneous connections) • Handling of static files, index files, auto-indexing and content negotiation • .htaccess per-directory configuration support • Reverse proxy with caching • Load balancing with in-band health checks • Multiple load balancing mechanisms • Fault tolerance and Failover with automatic recovery • WebSocket, FastCGI, SCGI, AJP and uWSGI support with caching • Dynamic configuration • TLS/SSL with SNI and OCSP stapling support, via OpenSSL or wolfSSL. • Name- and IP address-based virtual servers • IPv6-compatible • HTTP/2 support • Fine-grained authentication and authorization access control • gzip compression and decompression • URL rewriting • Headers and content rewriting • Custom logging with rotation • Concurrent connection limiting • Request processing rate limiting • Bandwidth throttling • Server Side Includes • IP address-based geolocation • User and Session tracking • WebDAV • Embedded Perl, PHP and Lua scripting • CGI support • public_html per-user web-pages • Generic expression parser • Real-time status views • FTP support (by a separate module) ==Performance==

Instead of implementing a single architecture, Apache provides a variety of MultiProcessing Modules (MPMs), which allow it to run in either a process-based mode, a hybrid (process and thread) mode, or an event-hybrid mode, in order to better match the demands of each particular infrastructure. Choice of MPM and configuration is therefore important. For delivering static pages, Apache 2.2 series was considered significantly slower than nginx and varnish. To address this issue, the Apache developers created the Event MPM, which mixes the use of several processes and several threads per process in an asynchronous event-based loop. This architecture as implemented in the Apache 2.4 series performs at least as well as event-based web servers, according to Jim Jagielski and other independent sources. However, some independent but significantly outdated benchmarks show that it is still half as fast as nginx, e.g. ==Licensing==

The Apache HTTP Server codebase was relicensed to the Apache 2.0 License (from the previous 1.1 license) in January 2004, and Apache HTTP Server 1.3.31 and 2.0.49 were the first releases using the new license. The OpenBSD project did not like the change and continued the use of pre-2.0 Apache versions, effectively forking Apache 1.3.x for its purposes. They initially replaced it with Nginx, and soon after made their own replacement, OpenBSD Httpd, based on the Relayd project. Versions Version 1.1: The Apache License 1.1 was approved by the ASF in 2000: The primary change from the 1.0 license is in the 'advertising clause' (section 3 of the 1.0 license); derived products are no longer required to include attribution in their advertising materials, only in their documentation. Version 2.0: The ASF adopted the Apache License 2.0 in January 2004. The stated goals of the license included making the license easier for non-ASF projects to use, improving compatibility with GPL-based software, allowing the license to be included by reference instead of listed in every file, clarifying the license on contributions, and requiring a patent license on contributions that necessarily infringe a contributor's own patents. ==Development==

The Apache HTTP Server Project is a collaborative software development effort aimed at creating a robust, commercial-grade, feature-rich and freely available source code implementation of an HTTP (Web) server. The project is jointly managed by a group of volunteers located around the world, using the Internet and the Web to communicate, plan, and develop the server and its related documentation. This project is part of the Apache Software Foundation. In addition, hundreds of users have contributed ideas, code, and documentation to the project. Apache 2.4 dropped support for BeOS, TPF, A/UX, NeXT, and Tandem platforms. ==Security==

Older versions of Apache were vulnerable to a denial-of-service attack called Slowloris, which creates many simultaneous partially completed requests, exhausting the server's pool of available connections. Since Apache 2.2.15, Apache ships the module mod_reqtimeout as the official solution supported by the developers. ==See also==