Launched in 1993, the Debian project is run as a 'distributed democracy' by electing project leaders and sorting out issues via a wide array of mailing lists and strict adherence to the project's social contract and a statement of purpose designed to keep the results of its work free and open.

Debian GNU/Linux is largely distinguished by rigorous quality assurance, a wide range of platform/architecture support [including Intel x86, Alpha, ARM, HP PA-RISC, PowerPC, SPARC, IBM S/390, and Itanium] and solid package management tools that make staying up to date and secure a snap.

The Linux distribution is obtained in several forms. Organizations can purchase it from Linux CD distributors, as a download of CD images and through a system called jigdo, which makes assembling a Debian CD from the project's global network of mirrors relatively simple and fast.

Debian is installable from a CD or over a network. If the installer is properly configured during the initial installation steps, the very latest patches and security fixes are downloaded from the Debian project's servers instead of their outdated counterparts on the installation media.

In general, the Debian project's approach to system management is quite simple. Packages with complex configuration choices are generally set up to query users for settings during installation, which simplifies the largely a text editor and command-line driven environment. The most "user-friendly" configuration tool available for Debian is probably Webmin, which shouldn't be underestimated in terms of utility. It does, however, rely on the user knowing it's been packaged and made available.

Debian is an excellent Linux distribution tended with much care and dedication by a global network of developers. Because of its relatively slow development cycle, it isn't the most cutting-edge in terms of the software available in the Linux world, but it is studiously maintained in terms of patches and security fixes. Consequently, Debian is a rock-solid and stable platform on which to run many infrastructure mainstays, such as DNS, file/print services, and Web servers. Its suitability for these purposes is limited only by the amount of in-house Unix/Linux expertise available in a given organization.

Unlike Red Hat and Novell, which aggressively seek partnerships with such enterprise notables as Oracle and IBM for their distros, the Debian project has little in the way of contact with that world, therefore technical assistance and application availability are a little tricky. This limits its range for applications found in many enterprise operations.

Visit the Debian Linux website for more info at www.debian.org

Take a look at the following facts :

* Yahoo uses FreeBSD to power one of the most popular Web servers on the Internet.
* The MP3.com Web site uses FreeBSD to serve pages and mp3 music files.
* Microsoft's Hotmail service uses FreeBSD for its email servers.

FreeBSD is known for having one of the fastest TCP/IP stacks in the operating-system world, which makes it a very suitable option for industrial grade networking & web-hosting servers.

There are a number of similarities between FreeBSD & Linux. Both work in roughly the same way, following UNIX conventions in terms of file locations filesystem structures.both use many of the same tools from the Free Software Foundation (including gcc) and in general if a software vendor supports Linux they will support FreeBSD as well.

However, FreeBSD was built from the beginning for heavy-duty networking and it can handle the high-traffic situations that Linux (and Windows NT) cannot.

FreeBSD can also be used in a variety of Internet situations outside of pure Web serving, especially in situations where security is a paramount consideration. Internally, there's kernel support for IP firewalling and IP proxy gateways, which makes FreeBSD very suited to be your firewall operating system. In addition, FreeBSD supports secure shells, Kerberos authentication, end-to-end encryption and secure RPC facilities.

There are several superb Web servers that are available for FreeBSD. FreeBSD itself ships with the Apache Web server. In addition, the Zeus Web server is available in a FreeBSD version.

The only drawback with FreeBSD is the lack of third-party applications in the e-commerce and application-server fields.

Visit the FreeBSD website for more info at www.freebsd.org

This is a FreeBSD Unix-based, open source operating system for POWER-based Apple servers. The Mac OS X Server runs on select POWER-based Apple machines: eMacs, iMacs, and Power Mac G3s, G4s, and G5s, as well as newer rack-based Xserves. The operating system require the hardware have built-in USB ports, 4 GB of free disk space, and a minimum 128 MB of memory.

The product ships as a media kit with a Getting Started guide and four CDs: two installation disks and disks for Admin Tools and Xcode Tools, Apple's developer compiler, and build project management software. There are 10 client to unlimited client licensing options & Volume pricing is also available.

The system is pretty easy to install in most cases, with the user just having to click 'continue' at various points.The installation can also be customized to leave out several unneccessary features which take up valuable server space.

Post-installation configuration is largely self-explanatory. AppleTalk has been wisely downplayed in favor of TCP/IP. The thumb rule with the Mac OS X seems to be 'When in doubt, choose the defaults', as you can always reconfigure later on using the Server Admin and Workgroup Manager tools.

Apple modularly divides administration tasks between the Workgroup Manager, for permissioning user, group, file and directory user access, and the Server Admin utility, for configuring and enabling a wide array of services from file sharing to virtual private networks.

While the Mac OS X can be considered as 'Unix for dummies and designers', the fact that it runs primarily on POWER processors makes it a niche product.

Visit the Mac OS X pages on Apple's website for more info at www.apple.com/macosx/

NetBSD is an ultra-portable and stable Unix variant of the BSD operating system family.Like the other two BSD flavors, is available as a free download. You can download the installation packages individually or as ISO format files suitable for burning onto a bootable CDR.

A minimal NetBSD install requires less than 100 MB of disk space and includes very few applications. The installation "wizard" is text-based but includes menus with sensible on-screen documentation. NetBSD assumes some familiarity with administrative tasks (e.g., partitioning a hard disk), but its menu-oriented approach helps you through the process. It even recommends settings for the typical situation.

NetBSD's speciality is its high portability, it will run on more than 50 hardware platforms ! This wide portability has gained NetBSD the reputation of being an ideal operating system for research environments. Organizations with older or marginalized or just plain unusual hardware systems can continue to make use of them for present-day work by installing NetBSD. Since NetBSD can run many Unix-like applications and is binary compatible with Linux, a wide variety of systems that might otherwise be obsolete can still be run on this OS.

Stability and scalability are among NetBSD's other strengths. Being portable to so many systems demands these capabilities. In a recent scalability benchmark, the current NetBSD release performed better than its BSD kin and nearly as well as the new Linux 2.6 kernel, which topped the rankings. But, unlike the comparably bulky Linux, NetBSD can squeeze down to fit into a huge variety of hardware environments.

Visit the NetBSD website for more info at www.netbsd.org

OpenBSD is the ultra-secure Unix variant in the *BSD operating system family OpenBSD, like many of the BSD variants, is obtained either via download or by purchasing a CD-ROM. The software itself is free and fully open source, although the CD-ROM distribution carries a $40 price tag that is a contribution to ongoing development.

The CD images are not available for download but the individual files are all freely available through links from the OpenBSD Web site. You can download a small bootstrap ISO that boots the OpenBSD installer and can then retrieve the rest of the system files either from CD or over the Internet (or via hard disk). The whole BSD installation is about 140 MB in size; opting out of extras, like games and the large X Windows GUI, saves at least 50 MB of download weight.

OpenBSD installation process is purely text-based and begins with a series of questions. For each question, a default answer is supplied.Read the questions carefully and select the best options to configure your installation. The Installation requires a certain level of familiarity with the OS and basic unix knowledge.

OpenBSD is designed to be secure from the beginning, every line of code has been continually audited for flaws and vulnerabilities. The initial install does not enable any system services that are not absolutely necessary for basic operation. It uses strong cryptography throughout the operating system. This means that even details as mundane as user passwords are encrypted using heavy duty algorithms.

But OpenBSD loses out on its scalability. OpenBSD performs significantly slower than comparable products in situations like a heavily trafficked Web server.But it will perform best for low-traffic Web sites requiring strong protection.

Visit the OpenBSD website for more info at www.openbsd.org

Redhat is probably the most popular Linux distribution around. It ships as either a collection of downloadable ISO images (available through the Red Hat Network) and a less robust support package called the "Basic Edition," or as a media kit with CDs and an installation guide with more support called the "Standard Edition."

The ES installation works the same as Red Hat Linux, It's graphical and mouse-driven and it's easy. The user is presented with simple options. Although the installer software does a good job of auto-detecting monitors and mice, it offers a chance to pick alternatives.Users can choose from general server options for such roles as file server (using NFS or Samba), Web serving with Apache, database services (with MySQL or Postgres), mail services (with sendmail as the default MTA and the option to provide POP3 or IMAP servers, or use alternative MTA postfix), and DNS services with BIND. Network configuration is quite straight-forward, with the option of using either a DHCP server or allowing the user to configure the IP, host name, and three DNS servers.

Most of ES' available services are at least somewhat configurable through a collection of graphical tools on the root user's desktop. More advanced performance tuning options are accessible if the user is familiar with the OS command line usage. Any detailed work will require getting under the hood and into the configuration files themselves.

The primary value of Red Hat Enterprise Linux ES is the support. Basic Edition customers get 30 days of installation and basic configuration support for their money. They can also expect a next-day turnaround on support calls, which are received during normal business hours across the United States. In addition, they receive a year of Web-based support, with a turnaround of two business days for queries.

Standard Edition customers receive what Red Hat calls its "ES Standard" support package: very specific help with a variety of configuration and installation tasks. The Standard Edition support package also includes a year of phone support, with a response time of four hours.

Red Hat is also compatibile with a broad array of business applications. Offerings from BEA, Oracle, Sybase, Veritas, and many others are all certified to run on top of Red Hat's product line.

Visit the RedHat Linux website for more info at www.redhat.com

Sun Microsystems' Solaris is the best-known and most widely used commercial Unix OS. In addition to offering enhanced functionality and manageability, the new Solaris version features a very wide variety of tools and add-ons, including the iPlanet Directory Server and Web Server, Samba support for integration with Windows networks, a choice of both the KDE and GNOME 1.4 interfaces, a Patch Manager for automating updates, and BASH , which can run most Linux shell scripts without requiring changes.

The Resource Manager is an improvement that will be welcome to server administrators, since it allows you to fine-tune & control of application resource allocation, including memory and processor utilization among multiple applications. A live updates feature allows patches and updates to the system to be installed without taking the server down, which is extremely useful in the 24x7 corporate environment.

The new Management Console is much easier to use than the old AdminTool and more fully integrated. The basic system tools and utilities have been updated as well, including sendmail 8.12, BIND 8.2.4, GNU wget 1.6, Samba 2.2.2, Apache 1.3.20, and Netscape 6.2.1. SunScreen 3.2, a full-featured firewall, is included and easy to install and configure.

There is a variety of freeware and open source utilities and productivity software which are included in the package, including the GNU grep, gzip, GIMP toolkit, several graphics libraries, the Libxml2 2.3.6 XML library, KDE Office, StarOffice and Star Suite.

The fact however remains that the limited versions of the directory server and Sun ONE J2EE and messaging servers cannot compete with available directory and application servers on Linux or Windows servers and Solaris is still more difficult to install and administer than most server operating systems

Visit the Sun solaris pages on Sun Microsystem's website for more info at www.sun.com

The German Linux company SUSE was aquired by Novell in 2003, which has positioned itself as the main competitor to U.S. Linux leader RedHat. SUSE Linux Enterprise Server 9 (SLES) is Novell's premier Linux distribution and is the first enterprise distribution to contain the 2.6 Linux kernel.

SLES 9 fills six CDs and consumes more than 3 GB, assuming the disk images are downloaded. SUSE relies on its exclusive YaST (Yet another Setup Tool) graphical front end to guide installation and system management.

YaST is the graphical front end to guide installation, system management and also the administrative heart of SUSE Linux. SUSE has evolved YaST over several versions and it is one of the most & comfortable graphical Linux administration environments available.

The 2.6 kernel features many significant enhancements over the previous 2.4 kernel. It includes developments aimed at high-powered servers, such improved memory sharing for multi-processor systems and support for Hyper-Threading. The new kernel has also received major boosts in the amount of RAM and number of physical devices that can be addressed. All of these improvements boost the usefulness of the software designed to meet enterprise management needs that ships with the operating system. The software covers areas like high availability fault tolerance, scalability across clusters, and event and intrusion monitoring.

For the enterprises looking to stay at the crest of the Linux wave, SLES 9 is a feature-rich offering with a state-of-the-art kernel and a strong administration environment in YaST.

Visit the Suse Linux pages on Novell's website for more info at www.novell.com

Microsoft Windows NT Server 4.0 was a high-end operating system with a bundled Web server. It was one of the leading operating systems in the Internet and intranet worlds. Part of the reason for this popularity was Microsoft's skill in positioning Windows NT Server as a useful corporate solution, with a slew of valuable tools and the ability to standardize.

Windows NT Server 4.0 was both a development and deployment platform. The other part of the equation was that overall, Windows NT Server 4.0 works pretty well as an Internet platform, especially on a small-scale or departmental intranet level.

Most of Microsoft's claims regarding Windows NT as a Web server were related directly to Internet Information Server (IIS) 4.0, which was bundled as part of the operating system. IIS was integrated with Windows NT Directory Services, making it easier to develop and integrate Web-based applications. IIS also integrated with other Microsoft tools: FrontPage, Microsoft Transaction Server, Microsoft Message Queue, Visual InterDev, various back-end tools, and Site Server.

But NT was not an OS for running mission critical servers. It lacked the stability and reliability of many of the Unix or Linux flavors. Though it did not dominate the server OS market, it did offer a option other than the Linux / Unix platforms. Over the years, 6 service packs were released , along with numerous patches and fixes to address the reliability problems.

The OS has been officially retired by Microsoft & effective January 1, 2005, Premier, pay-per-incident and security update support will no longer be available for Windows NT Server 4.0 (Standard, Enterprise Edition, and Terminal Server Edition).

Visit the Windows NT pages on Microsoft's website for more info at www.microsoft.com

An operating system that underwent continuous evolution, Windows 2000 Server was neither perfect nor the best OS you could implement on your server. But with the familiar user friendly interface of Windows & the easy to use 'Wizard's to accomplish most tasks, it has pushed the envelope of competition with Unix (and now Linux) as the OS for the enterprise.

The Windows 2000, based on the NT platform was a improvement over the latter. Faster, more resource efficient & stable than NT, it had been reorganized and rationalized. The highlight of Win2K was the Active Directory system. An operating system directory service provides the means to record and organize the resources of a network (people, computers,and peripherals), control their security, and monitor their operation. This information becomes much more accessible in Active Directory and is used throughout the operating system. It is also required for features such as Kerberos authentication.

Windows 2000 Server bundled the IIS Web server into the package. It was faster, more robust than before. Also part of the Internet/intranet package is support for multimedia, including Windows Multimedia Services, Windows Quality of Service (to ensure that streaming multimedia receives necessary bandwidth), Resource Reservation Protocol, and asynchronous transfer mode support.

There were many performance enhancements in Windows 2000 Server. A good deal of code optimizing was also done resulting in an improvement of 10% to 20% over NT. There were four service packs released for Win2K which addressed a number of security, stability & other issues that were encountered.

With the release of Windows Server 2003 earlier this year and after nearly four years in the marketplace, Microsoft has announced that Windows 2000 Server, Windows 2000 Advanced Server and Window 2000 Server Client Access Licenses (CALs) will be retired in phases. Customers who are in need of a copy of Windows 2000 Server or Advanced Server can obtain a copy of Windows Server 2003 and exercise their downgrade rights.

Visit the Windows 2000 pages on Microsoft's website for more info at www.microsoft.com

Windows Server 2003 is a scaled family of server editions that attempt at delivering Microsoft's long-promised and long-awaited mature operating system. This may mean that Microsoft (finally) has a server that can handle the enormous loads of a major enterprise, or that it has a reasonably priced server that can be easily managed by the limited resources of a smaller company.

With this release Microsoft has certainly met a very high standard in the big four criteria: security, reliability, scalability, and performance. In addition, for some organizations Microsoft getting it right means having the correct special features. It also means competing with an industry-leading ease of use and the right pricing.

To meet these requirements, Windows Server 2003 is delivered in several editions, Web, Standard, Enterprise, and Datacenter, that have different capacities and price tags.

Along with the Windows Server 2003 Microsoft also created the .NET framework for application development. Programmers will discover that this server, along with its built-in application server elements and the revamped Web server, are a particularly effective environment for .NET applications. Provided, of course, that Microsoft Visual Studio .NET is the development tool of choice.

Being an evolution of NT & Win2K, Windows 2003 has retained most of the stable features of the previous two editions & is miles ahead of them in terms of reliability, stability & features. However it is still not in the same league as FreeBSD or NetBSD when it comes to mission critical applications. With a wide range of development tools & addons available for the Windows platform, Win 2003 is still one of the 'easier' OSs to deploy and use. But when it comes to price-tags, it is probably the most expensive server OS system available.

Visit the Windows 2003 pages on Microsoft's website for more info at www.microsoft.com