Version 2.0 of the world's most popular Web server, Apache, is finally available. Apache 2.0 initially was expected by the end of 2000 but only entered beta testing in April 2001.
After three years of development the new version, which has a radically different architecture from previous versions, is now considered stable enough for production use, according to the Apache HTTP Software Foundation.
The open-source Apache software, a competitor to Sun Microsystems' iPlanet Web server and Microsoft's Internet Information Server, is used to send Web pages from servers to browsers. But Apache's software serves more Web sites than all other servers put together, and this latest version adds more performance and features to an already feature-packed piece of software.
Apache 2.0 is now able to run using threads on platforms that support them, as opposed to its previous method of using multiple processes. Threads are separate paths through a program that share memory, whereas processes each have their own memory space. This makes threads a more scalable way of running several tasks, such as serving multiple different Web pages, at once. The Apache Software Foundation hasn't released any figures for the performance improvement this brings, but claims that most configurations will benefit from the change.
Apache now also runs equally well on non-Unix platforms, such as Windows or NetWare, as on Unix. Previously, the server software has run poorly on Windows, and has been seen by some as a Unix-only technology. Its adoption on Windows has also been hampered by the inclusion of Microsoft's Internet Information Server (IIS) with Windows NT and Windows 2000.
Apache 2.0 also supports IPv6, the new version of the Internet's underlying protocol. IPv6 is needed to help relieve the shortage of Internet addresses available, among other things. The underlying operating system needs to support IPv6 for this to work. There's also native support for secure sockets layer (SSL), the encrypted communication system used for secure Web pages such as online ordering. Other enhancements include support for WebDAV, a standard for remote, distributed document authoring.
Apache is used on over half the world's Web servers, according to the Netcraft survey, which monitors the Web servers used for each Web site it scans. While some sites have been using pre-release versions of Apache 2.0, this is the first time the Apache Software Foundation has considered it stable enough to use on a production server. Development of the previous version of Apache continued while version 2 was still in beta, and will still be available for people who don't want to upgrade straight away.