KVM switch

Definition of KVM switch in The Network Encyclopedia.

What is KVM switch?

Stands for Keyboard-Video-Mouse switch, an electronic switch that allows one or more keyboards, video monitors, and pointing devices to control a number of computers.

You can use KVM switches to cut costs and prevent equipment clutter in server rooms. Cheaper KVMs sometimes use pushbuttons for selecting computers, but more sophisticated KVMs allow you to select a computer by using a keyboard shortcut or by selecting from an on-screen context menu.

The menu might also include some form of password protection for each computer and a master password that grants access to all computers attached to the switch. KVMs can support two, four, or eight computers, and some KVMs can be daisy-chained to support many more computers.

Another use for a KVM arises when your servers are in a special “clean room” or secured location and you want to control them from a different room. In this case, the KVM switch must include a built-in video extender, which amplifies the video signal so that the monitor can be connected to the computer using a cable that is 500 feet or longer. In this configuration, you must use two video extenders, one at the server and one at the remote monitor station. Video extenders can often be connected using a single interconnect line of category 5 cabling.

Graphic K-4. KVM switch.

Other, similar types of switches include the following:

  • KV (Keyboard-Video) switch
  • KVMM (Keyboard-Video-Mouse-Monitor) switch

External references