Network Computingwww.networkcomputing.com

KVM switches control servers on a wide range of hardware platforms with a variety of operating systems, video resolutions and input devices. We connected our units under test to a number of typical boxes running Microsoft Windows 9X/NT, Sun Microsystems and Linux operating systems, with a variety of pointing devices and keyboard types attached. Our machines ranged from Compaq Computer Corp. ProLiant and Dell Computer Optiplex 600-MHz servers to Sun workstations and low-end Pentium 166-MHz PCs. Network control of KVM switches was tested in a predominantly Cisco Systems 10/100 environment, along with dial-up control over POTS lines via serial interface where possible.

We evaluated the ease of switch setup, including direct terminal access for administrative functions such as flash firmware upgrades. Switch configuration was performed in numerous ways because of differences in embedded firmware, but a host of enterprise-type scenarios was set up for all switches. User configuration and security features were manipulated, as was each channel's setup -- including testing at all possible video resolutions. We examined keyboard and mouse compatibility, as well as keep-alive functions, which we tested through simulated power interruptions and broken connections.

Distance was a critical factor in our product evaluation, with Cat 5 wiring the medium of choice for extending connection and user distances out to 500 feet -- and in some cases 1,000 feet -- in our large data-center simulations.