One of the easiest things to overlook when designing our View infrastructure is how much network bandwidth is required to support the View Client connections. The preferred protocol for VMware Horizon View is PC-over-IP, commonly known as PCoIP. View also supports the use of Microsoft Remote Desktop Protocol (RDP).
PCoIP is a display protocol provided by VMware for use in the View product suite. The PCoIP protocol has multiple features that make it ideal for connecting to View desktops:
Capable of adapting to varying levels of connection latency and bandwidth
Has multiple built-in techniques for optimizing and accelerating connections over a wide area network (WAN)
Able to achieve compression ratios of up to 100:1 for images and audio
Uses multiple codecs that enable more efficient encoding and decoding of content between the Virtual Desktop and the remote Client
Based on User Datagram Protocol (UDP), which eliminates the need for latency-inducing handshakes used in Transmission Control Protocol (TCP)-based display protocols
Microsoft RDP is a TCP-based display protocol that does not have many of the WAN optimization and acceleration techniques that are found in PCoIP. In addition, VMware Horizon View includes Microsoft GPO templates that enable a very granular control over PCoIP connection characteristics. Chapter 13, Implementing VMware Horizon View Group Policies, provides information about how to use the View GPO templates to control the settings of the PCoIP connections.
The VMware Horizon View Architecture Planning guide (http://www.vmware.com/support/pubs/view_pubs.html) provides estimates for PCoIP bandwidth utilization based on the application workload of the client. The following table is built upon that information:
|
User type |
Workload characteristics |
Bandwidth in Kbps |
|---|---|---|
|
Task Worker |
2D display and single monitor. Web and limited Office applications. |
50-100 Kbps |
|
Knowledge Worker (2D) |
2D display and single monitor. Office Applications. |
100-150 Kbps |
|
Knowledge Worker (3D) |
3D display (Windows Aero) and multiple monitors. Office Applications. |
400-600 Kbps |
|
Knowledge Worker (3D)—High Use |
3D display (Windows Aero) and multiple monitors. Office Applications. Frequent display changes. |
500 Kbps-1 Mbps |
|
Power User |
3D display (Windows Aero) and multiple monitors. 480P video and images frequent screen changes. |
2 Mbps |
Bandwidth utilization is heavily dependent on a number of factors, many of which can be controlled with the View PCoIP GPO settings or even Windows Virtual Desktop settings. Actual bandwidth utilization will vary based on usage and PCoIP settings.
Note
The PCoIP protocol was invented by a company called Teradici. For additional information about how the protocol works, visit the Teradici PCoIP technology page (http://www.teradici.com/pcoip-technology.php).
Even with a careful analysis of user desktop usage patterns, it is important to remember that there will be spikes in usage from time to time. A Knowledge or Task Worker who has a need to use an application with a large amount of screen changes, such as viewing images in succession or watching a video, may cause a brief bandwidth spike of between 500 Kbps and 1 Mbps or more. Preparing for these spikes in bandwidth utilization is important in order to preserve the quality of service for all of the View Client connections.
Refer to Chapter 11, Creating a Master Virtual Desktop Image for information about optimal settings for a Windows desktop, and Chapter 13, Implementing VMware Horizon View Group Policies for information about how to configure PCoIP settings to reduce bandwidth needs. The information contained in both of these chapters is critical to optimizing View Client connections and Virtual Desktop performance in general.