John mentions "The newer management net is Ethernet..." This is not always the case.

Traditionally, this "management net" has been called a "KVM network" and when encompassing power or other remote control devices it’s called a "maintenance network". Regardless of what you call it, these networks have been around since the mid 1990s.

Originally, the KVM network was designed around analog KVM switches and accessed entirely via proprietary protocols – communication methods locked away in the trade secrets of KVM vendors. In a nut shell, it takes a lot more than a programmer familiar with Windows and TCP/IP to hack them. These systems continue to provide real time access with crisp high resolution video support and zero delay in keyboard and mouse activity.

When Ethernet access is provided (ie: KVM over IP), the KVM network is no longer an isolated network or separated because the entry point is through the data network. Extending accessibility outside the data center and from offsite locations is a point for security concerns. Care should be taken to minimize risk understanding most security approaches impact overall performance.

Remote-management cards are also considered KVM over IP devices. Unlike KVM over IP switches, there’s a notable lack of consolidated analog support so analog KVM is used to access the same servers from inside the data center. And, the cost is considerably higher when calculating expense related to the required infrastructure.

It’s important to know where, when and how these types of KVM networks should be used. Analog systems provide real time out-of-band access and users can be anywhere from 500 to 1500 feet from the data center without compromising security or performance. And, the latest fiber based KVM extension technology allows operators to be up to three miles from the data center.

Both types of KVM over IP provide out-of-band access to servers using in-band access methods. It’s great for geographically dispersed operations where lower video quality and erratic mouse operation offsets the cost of travel and response time.

Ethernet KVM switch deployment is easier to understand but require additional steps for network setup on each device. Analog KVM infrastructures offer greater user throughput, better performance and increased security. Analog infrastructures can be adapted for TCP/IP access so the data center can take advantage of both.

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