When choosing an NOS, you should certainly weigh the strengths and weaknesses of the available options before making a choice. Nevertheless, your decision will probably depend largely on the operating systems and applications already running on the LAN. In other words, your choice may be limited by the existing infrastructure.

The following is a list of factors to consider when selecting a NOS:

• Meeting resource security requirements.
• Existing staff capable of managing it.
• Ability to support additional needed services (meriting the upgrade).
• Developer support service quality.
• Compatibility (with current infrastructure and applications)
• Required training.
• Scaleablity
• Cost.

Even after addressing the above factors, you should test the qualifying NOS in your environment before making a purchase. Such testing should be done on an extra server, commonly referred to as a test server, and perform evaluation using a test group of typical users and applications with specific test criteria in mind as trade magazine articles and/or a vendor’s marketing information cannot accurately predict which NOS will best suit your particular circumstances and/or organization..