What does WIKIPEDIA say here?
To extend the permissible distance between computer and KVM switch or between KVM switch and workstation, there are KVM extenders that transmit the keyboard and mouse signals without interference and the video signals without too much loss of quality over greater distances than would be possible without amplification.
In contrast to a pure amplifier for the signals, other cable types can often be used here, in particular Cat5 cables with modular connectors (colloquially RJ45), as used for Ethernet (100BaseTX or 1000BaseT). Therefore, the infrastructure that is usually available or needed anyway can be used even more flexibly, namely to extend the KVM lines. For this purpose a cable (eight-wire) is completely occupied, the simultaneous use with Ethernet or TCP/IP is not possible, unlike KVM over IP (see KVM connections over a network). Depending on the cable length and information from the manufacturer, a larger cable cross-section than for Ethernet may be required in order to limit the signal attenuation to permissible values.
One device is connected to each end of the line, typically a transmitter and a receiver device. Both must match each other, so they are usually sold as a pair.
What we say here from KVM-TEC
For us, KVM extenders are the ultimate power boxes, capable of transmitting video and USB signals over long distances ( up to 160km/99mi) without any loss of quality. We have taken great care in developing our own compression to achieve visually lossless ultra-low latency of less than 2ms (1.38ms to be precise). For 4K extenders with a simultaneous color encoding of 4:4:4 with 24-bit color depth ( 8 bit per color) and 60 Hz refresh rate. This allows lag-free operation and there is no jerking or stuttering of the mouse.
kvm - tec extenders are available in CAT and Fiber, as PoE version, redundant, and as the industrial version for high-temperature ranges. The kvm-tec extenders are also suitable for 24V applications.
kvm-tec extenders over IP are compatible with standard network components and can be used in matrix switching systems up to 2000 endpoints and more.
Like everything at kvm-tec, USB 2.0 transmission was developed in-house. This has a great advantage for our users that we can adapt our USB. Now and in the future. Since new USB devices are constantly coming onto the market, it is an extremely important factor that the USB packages are changeable. What took us a lot of development time, in the beginning, is now proving to be a big advantage.
Our KVM powerboxes are available as send (local/TR) and receive (remote/RX) units, or as a set.
The kvm-tec whitepaper gives an overview of the current global KVM extender market and the corresponding solutions and provides a detailed segmentation of the market by type and end user. Furthermore, it analyses future developments and requirements.
Many renowned institutions in various markets, including Public Safety and Emergency Centers, Utility and Power Control Rooms, Medical Technology and Hospitals, Traffic Management, Airports & Air Traffic Control, Process Industries, Conference Centers and Educational Institutions, Broadcast, Film Television, Events and Museums, Digital Signage & POS rely on high performance KVM solutions.