Connecting KVM Swithces
Every KVM needs a way to connect the remote computer to your keyboard, mouse and monitor. This can be done with physical connections using PS2 or USB cables as with most home KVM switches, Cat 5 cabling for extended distances, or encrypted IP data through the network.
Most inexpensive KVM switches are connected to all the switched computers via local cables. Older models will require connection from the PS2 Keyboard, mouse, and video ports on each computer to be controlled to the PS2 Keyboard and mouse ports on the KVM switch. Newer models connect with USB cables and also can connect the microphone and speakers. The physical keyboard, mouse and video are in turn connected to the KVM switch.
When using a Cat5 KVM switch, a remote box connects to each computer’s keyboard, mouse and video connectors. A Cat5 cable then is routed back to the KVM switch and connected. Although these can be run through patch panels, it’s important to keep in mind that the cables are not Ethernet compatible, so it’s important not to connect them to your network switch. It is also important to avoid connecting an Ethernet cable to the KVM switch. These switches usually come with a software utility used to select available machines. Most of the Cat5 KVM switches have separate ports for the servers and the users. Each user has a box (different from the module for each server) that connects it to the KVM. The keyboard, mouse, and video at the user station connect to the user controller box. Most of the time, a local computer can also be connected to the KVM’s user station as well.
IP KVMs can connect to computers in two different ways. Some use a hardware device (usually PCI or mCard) to be installed into remote machines. This captures the keyboard, mouse, and video connections and converts it to an IP connection with the KVM box. Another method connects an external transponder to the keyboard, mouse, and video connectors to the machine. In either case, keyboard, mouse, and video data is encrypted between it and the KVM switch. Users can log in to the KVM via a Web browser interface that allows them to choose which computer to control.