What Is a KVM Extender?
A KVM extender is a device that allows you to use your keyboard (Keyboard), display (Video), and mouse (Mouse) at a distance from your computer.
Typically, the cable connecting the keyboard, display, and mouse (KVM station) to the computer is designed to be no longer than about 10 meters. Using a cable longer than about 10 meters will result in digital signal attenuation and waveform distortion, which will prevent proper data transfer.
With KVM extenders, connections can be made over CATx cables up to about 150 meters, and even farther over fiber optics or networks, while maintaining the quality of the digital signal.
Uses of KVM Extenders
KVM extenders are primarily used to isolate computer units from human view for security and maintenance reasons.
1. To Streamline Work in a Server Room
KVM extenders allow users to operate servers from a remote location without entering the server room. Server room staff does not need to physically approach the servers. This reduces the burden and travel time of the server room staff.
2. To Make the Best Use of Desktop Space
With a KVM extender, the PC itself can be removed from the desktop. This not only saves desktop space but also simplifies wiring and maintenance.
3. For Security Purposes
With a KVM extender, the main computer unit can be protected by surveillance cameras and locks. This prevents leakage or tampering with confidential information or important data.
4. When Securing the Computer’s Operating Environment
Computers can be installed in a secure and stable environment away from outdoor live event venues with huge screens.
Principle of KVM Extenders
A KVM extender is a mechanism that physically separates a computer from its keyboard, monitor, and mouse, converts the signals between them, and transmits the signals over long distances via CATx or The KVM extender is placed between the computer and the keyboard, monitor, and mouse, converting the signals and transmitting them over CATx or fiber cables that can carry data over long distances.
KVM extenders can be connected to multiple computers over a network, as well as one-to-one connections. In this case, a technology called KVM over an IP extender is used.
Types of KVM Extenders
KVM extenders are classified according to the type of signal they carry and the type of cable they use.
1. Classification by Signal
Signal types include video signals such as analog VGA and digital DVI, keyboard and mouse signals such as USB and PS/2, and audio signals. A combination of these signals can also be transmitted.
2. Classification by Cable
Cable types include twisted pair cables such as Cat5 and Cat6 (CATx cables) and fiber optic cables. CATx cables can extend up to 130 m to 300 m, while fiber optic cables can extend up to 20 km.
There are also KVM extenders, called KVM over IP extenders, which allow access to multiple computers over a network, as well as one-to-one connections. In this case, signals are converted and transmitted over an IP network.
How to Choose a KVM Extender
When choosing a KVM extender, you need to decide on the type of signals and cables you need for your application and environment.
1. Signal Type
Signal types include video signals such as analog VGA and digital DVI, keyboard and mouse signals such as USB and PS/2, and audio signals. Select a product that matches the interface of the keyboard, monitor, and mouse to be connected.
2. Cable Length
Cables include twisted pair cables, such as Cat5 and Cat6 (CATx cables) and fiber optic cables. CATx cables can extend up to 150m to 300m, while some fiber optic cables can extend up to 20km.
3. Connection to Multiple Computers
Some KVM extenders are called KVM over IP extenders, which allow not only one-to-one connection, but also access to multiple computers over a network. In this case, signals are converted and transmitted over an IP network.
4. High Resolution and Security
Consideration should also be given to whether security requirements, such as 4K video and protection of sensitive information, need to be addressed.