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Control room professionals demand seamless USB performance when accessing mission critical systems via a KVM solution in government, health care and industrial applications. To help you make the right choices when selecting your next mission critical, KVM over IP system we have created this handy five-point guide.

Why aren't all KVM systems the same?

Many KVM over IP solutions prioritize low latency over seamless USB interaction. An off-the-shelf chipset will often be used by other manufacturers to save R&D time, resources, and money. The downside to this approach is that USB and video performance are not always optimized to work together. As new features or other driver-based requirements are required, there could be a long wait for the third-party development team to deliver an update if it is even possible to do so!

Leading KVM manufacturers choose to design and develop their own USB hardware and software implementation, which makes it much easier to tie together USB and video performance, add innovative USB feature sets, and be much more adaptable to end user requirements.

How do I evaluate KVM over IP USB performance?

Without access to expensive, high-end test equipment, it can be tough to scientifically measure USB performance in a KVM over IP solution. What makes this even more of a challenge is that performance levels are measured in milliseconds rather than frames. What might surprise you is that the human eyeball combined with normal levels of hand/ eye coordination is a quick way to check for performance. This makes sense as it is not only the latency of your human interface devices (HID’s), such as a mouse or tracker ball that matter, but also the way the system feels in terms of hand/eye coordination.

First, select a PC that you want to control from your operator workstation and use your mouse to control the PC/MAC application. Does what you are seeing not quite match up? Can you feel a lag? If so, the performance is above 5 milliseconds, which is the maximum we normally feel as usable.

Next, if the KVM has the feature, switch the view to see four PC’s on a single display. You may already be seeing issues as quad source operation can often by reduced to only refresh a few times per second. If this is not the case, and you are seeing a normal level of screen refresh, repeat the mouse usability test in the quad-screen mode.

Does the USB performance meet your everyday requirements?

Although the latency and feel of USB is essential, so is the requirement for total transparency of use to the end user. For example, what happens when your PC “goes to sleep”? Can the operator bring the computer back to use from their workstation? This is a simple task if your PC is next to you, but when your computer is not and if your solution is missing this feature, your productivity and response time may suffer.

Additionally, check that your chosen KVM solution accepts any kind of USB peripheral, often called “HID’s” (Human Interface Device), without limitations in high-speed mode. Operators demand access not only to a keyboard and mouse, but also to other peripherals such as cameras and headsets. Connectivity is only one part of the requirement; the KVM control software should give you options to control every aspect of USB connectivity.

Finally, ask how many USB connections you can make to the KVM receiver at the workstation without adding potentially expensive options or hubs. It is also important that the USB implementation is compatible with the devices your operators use on a day by day basis including headsets, webcams, printers, and barcode readers.

What about USB mass storage devices?

Check that your chosen KVM solution allows access of storage such as USB sticks and mass storage drives. Also, ensure you have the option to block USB devices in secure applications to prevent copying of classified or commercially sensitive material or, alternatively, in situations where there is a risk of viruses being introduced from USB devices. Also, ask if you can grant temporary, supervisor level permissions for those occasions when you do want to allow USB file transfer.

Multiuser control matters

Superior KVM solutions, such as Magenta Pathfinder, make it possible to display a source on multiple user workstations simultaneously, which can speed up decision making and increase situational awareness in a control room team.

If your solution offers screen sharing, it is essential to check whether USB control over that common device can be prioritized. Pathfinder allows every control room operator to have a unique login and password while also assigning a priority level for USB control in screen-sharing situations.

For example, the control room supervisor would have a higher priority than an operator, and if they took control with a mouse or keyboard, they would automatically take control without any other intervention, therefore removing workflow blockages.

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