There is often a misconception of the difference between a KVM Extender and KVM Over IP. The general definition of a KVM Extender is a device that allows you to extend the distance between your console (Keyboard, Monitor, Mouse and other peripherals) and your computer. In that sense KVM Over IP technology is a KVM Extender but it is much more than that. There are two types of KVM Extenders; Analog KVM Extenders and Digital KVM Extenders.
Analog KVM Extenders
With Analog KVM Extenders there are three types that you can use:
1. Coax KVM Extension Cables
With Coax Extension Cables you can extend your Keyboard, Monitor and Mouse (generally no other peripherals are supported) up to 60′ uses bonded KVM Cables. While these cables are much less expensive then the other KVM Extenders available the cables are much bulkier and more cumbersome to run than their counterparts. Another important note about these cables is that the possibility of video degradation is quite high going these distances. The general rule is you should not run a video cable that is longer than 30′ or you should expect some video loss or ghosting.
2. Cat5 KVM Extenders
Cat5 KVM Extenders are the most popular of the group since they offer the most flexibility and compatibility for the cost. If you need to extend your console less than 1,000′ and can run Cat5 from your computer to your console then a Cat5 KVM Extender will be the best solution for you. You can use already existing Cat5 in your building as well to simplify the process. This cable can not be going through any hub or switch and has to be point-to-point. Manufacturers say the cable has to be from end to end without going through any patch panels but we have done installations where it has worked without any problems. If you are going through a patch panel make sure all the connections are correct and secure before proceeding. If you go through a patch panel and are having problems we will recommend trying it without a patch panel to see if the unit is still good.
With Cat5 KVM Extenders there are some that also offer to extend serial and audio devices. For most instances these are not necessary but there are instances where these options would be essential. For instance, if you work in a recording studio and need to have your console in a silent room you could put your Keyboard, Monitor, Mouse, Speakers and Microphone in the room with you and have your computer isolated in another room so the noise can not be heard. A great selection for this would be the Avocent LongView LV830-AM since it is a multimedia KVM Extender that also allows you to have a local console next to the computer in addition to being up to 500′ away.
3. Fiber KVM Extenders
A Fiber Extender is a very niche product and the least common of all. They offer the benefits of offering great video quality and being able to do this at very long distance. The Fiber Extender can allow you to extend your console up to 10,000 meters or 6 Miles on only 2 strands of fiber. The majority of installations with Fiber Extenders are on campuses with fiber already laid and also in instances where security is of major concern and KVM Over IP is out of the question.
Digital KVM Extenders (KVM Over IP, KVM Over IP Access, KVM Switch Over IP, etc…)
The most versatile extender is a Digital KVM Extender or KVM Over IP. Due to trademark issues there are many different terms that mean accessing your computer(s) over the internet. The most common term is KVM Over IP. Digital KVM Extenders allow you to access your computer over the internet with varying degrees of options and security. KVM Over IP can be used to access a single server or a whole data center depending on the unit you purchase. The category is too large to cover in one paragraph so that will be the topic of a later post.
KVM Over IP is great when you need to access your computer(s) from outside of the building or in a building where you can not have a Cat5 cable point-to-point. There are software packages out there that allow you to access your computer over the internet and they are much less expensive than KVM Over IP but they have limitations. If the software locks up you have no way to fix it. If you need to reboot your computer you will lose your connection. With a hardware based solution you are able to act like you are sitting in front of the computer without worrying about the software locking up.
KVM Over IP is generally used in Data Center or Server Room environments where they have a large number of servers to control or when there is a critical server that someone may need to access when they are not in the office. KVM Extenders are great tools that have many different installation applications.