What is a KVM Switch?
A KVM (Keyboard, Video, Mouse) Switch is a device that allows you to control multiple computers from a single keyboard, video monitor and mouse console. This can be particularly beneficial when there is insufficient room for multiple monitors and keyboards (e.g. in a server room rack or on a small desktop).
How Does a KVM Switch Work?
Computers that the user wishes to control are connected to the KVM Switch using special KVM cables. A keyboard, monitor and mouse are then connected to the KVM Switch. Control is switched from one computer to another by the use of a button, On-Screen Display (OSD) controls, or hot keys on the keyboard, with the KVM routing signals between the computers and the keyboard, mouse and monitor as appropriate.
KVM Switches differ in the number of computers they can control, ranging from two up to 32 computers. Enterprise-level KVM Switches can also be daisy-chained or cascaded to allow even greater numbers of computers (over 4,000) to be controlled from a single keyboard, video monitor and mouse console.
Important KVM Switch Features
In addition to the basic KVM functions described above, some KVM Switches include features that may be especially valuable in certain situations.
- Plug-and-play setup—no complicated software is required
- Hot-pluggable—easily add or remove computers without powering down the KVM switch or other computers
- Compact designs save valuable rack enclosure and desktop space
- Microphone and audio computer support
- Wireless keyboard and mouse support
- Auto-scanning function automatically searches for all connected computers
- Daisy-chain and cascading capability to allow connection to over 4,000 computers
- Compatibility with all major operating systems
- Control of PS/2, USB and Sun computers using the appropriate KVM cables or adapters
- Password security features for multiple users and an administrator
- IP remote access built-in or via a separate unit allows remote control via the LAN, WAN or the Internet
- Built-in firmware upgrade capability
- Cat5 computer connection for distant control up to 500 ft.
- Simultaneous control by up to four independent users
- Superior video quality up to 1920 x 1440 pixels
- VGA and DVI video connections
How Can I Compare and Choose the KVM Switch I Need?
KVM Switches are available in a variety of rackmount, rackmount console and desktop designs with up to 32 ports. When choosing a KVM Switch, you should consider the following:
- How many computers you want to control from a single KVM Switch
- How far away do you need to control the connected computers (maximum distance from the connected computer to the KVM switch)
- Do you currently have a keyboard, monitor and mouse or do you need a KVM Switch with the keyboard, monitor and touch pad built-in (a console KVM Switch)
- The type of computers you need to connect: PS/2, USB or Sun connectors
- The type of monitor you want to connect: VGA or DVI
Typical KVM Switch Applications
Space-saving, convenient and economical, a KVM Switch is flexible enough to meet the needs of any home office, small/mid-size or enterprise application. Plus, a KVM Switch is easy to install, configure and operate. KVM switches are popular among users who have upgraded their home computer systems and want to still use their old computers but do not want to invest in a second keyboard, monitor and mouse. KVM switches are also used by businesses to save money when one person uses more than one computer and in server rooms where it is only necessary to periodically access each server one at a time. They are frequently used in data centers where multiple servers are placed in a single rack with a single keyboard, monitor and mouse. A KVM switch then allows data center personnel to connect to any server in the rack.