Highly efficient delivery of desktops over IP networks – especially WAN links:

PCoIP technology enables key features to optimize the delivery of a user’s desktop over standard local area and wide area networks (LAN and WAN). One of these features includes a progressive image refinement that allows a compressed image of the user’s desktop to be delivered quickly over the network and then a progressive refinement to an exact image of the user’s hosted desktop. This allows for a highly efficient desktop delivery over IP networks – especially WAN networks (long latency and possibly low bandwidth networks). In an interactive user session, the user may have moved to a follow-on action that eliminates the need to send the rest of the display pixels resulting in an efficient desktop delivery – and a significant benefit compared to solutions.

WAN PCoIP User Scenario:
The user’s desktop is delivered over a low bandwidth link across North America (~90-100ms round trip network latency). The user clicks on a web page (or a document, PowerPoint, 3D model, etc) and a highly-compressed, initial image is delivered quickly where the image is slightly grainy but the text is still clear and readable.

Initial highly compressed image – but clear text

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PCoIP intelligently compresses the user display to ensure that in a constrained scenario (long latency, low bandwidth) the display text is still as crisp as if the desktop were local. However, images and video are highly compressed to minimize the network bandwidth load and to deliver the initial display image extremely quickly to ensure a responsive user desktop.

Perceptually Lossless – still compressed, but users cannot tell

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The image is progressively refined and will reach a point we call “perceptually lossless” or the desktop appears to be an exact image of the source desktop at the host. However, in reality, there is still compression present and if there is still time (before the display is changed, window is moved, or hyperlink is clicked, the system will continue to build to a fully lossless image – or an exact image as the source display at the host.

The time it takes to refine the image depends on the available network bandwidth, but in most cases it is not possible for the user to see the refinement in progress. It just looks the same as if the PC was at the user’s desk.

Fully refined image – exact image as the source display in the host PC

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Key benefits of progressive refinement in a WAN desktop delivery

• Text delivered as exact image
  Text is sent as a lossless image so that users can always read text even if surrounding images are compressed
• Desktop clarity at any distance
  Progressive refinement enables full image clarity and A fully crisp desktop display regardless of the distance
• Highly responsive desktop
  Get an initial image quickly then build to a fully crisp desktop
• Network bandwidth efficiency
  Do not send additional pixels if the users has changed something on the screen

Progressive refinement to an exact or lossless image is a critical feature for detailed image analysis whether it is for medical diagnostics, design engineering analysis or other applications that simply cannot have compression artifacts in the displayed image.