5.0

Optimization Controls Available with PCoIP
If you use the PCoIP display protocol from VMware, you can adjust several elements that affect bandwidth
usage.
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You can adjust the size of the image cache on Windows and Linux client systems, from 50MB to 300MB.
Image caching reduces the amount of display data that must be retransmitted.
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You can configure the image quality level and frame rate used during periods of network congestion. The
quality level setting allows you to limit the initial quality of the changed regions of the display image.
Unchanged regions of the image progressively build to a lossless (perfect) quality. You can adjust the
frame rate from 1 to 120 frames per second.
This control works well for static screen content that does not need to be updated or in situations where
only a portion needs to be refreshed.
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You can also turn off the build-to-lossless feature altogether if instead of progressively building to perfect
quality (lossless), you choose to build to perceptual lossless.
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You can control which encryption algorithms are advertised by the PCoIP endpoint during session
negotiation. By default, both Salsa20-256round12 and AES-128-GCM algorithms are available.
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With regard to session bandwidth, you can configure the maximum bandwidth, in kilobits per second, to
correspond to the type of network connection, such as a 4Mbit/s Internet connection. The bandwidth
includes all imaging, audio, virtual channel, USB, and control PCoIP traffic.
You can also configure a lower limit, in kilobits per second, for the bandwidth that is reserved for the
session, so that a user does not have to wait for bandwidth to become available. You can specify the
Maximum Transmission Unit (MTU) size for UDP packets for a PCoIP session, from 500 to 1500 bytes.
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You can specify the maximum bandwidth that can be used for audio (sound playback) in a PCoIP session.
WAN Support and PCoIP
For wide-area networks (WANs), you must consider bandwidth constraints and latency issues. The PCoIP
display protocol provided by VMware adapts to varying latency and bandwidth conditions.
If you use the RDP display protocol, you must have a WAN optimization product to accelerate applications
for users in branch offices or small offices. With PCoIP, many WAN optimization techniques are built into the
base protocol.
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WAN optimization is valuable for TCP-based protocols such as RDP because these protocols require many
handshakes between client and server. The latency of these handshakes can be quite large. WAN
accelerators spoof replies to handshakes so that the latency of the network is hidden from the protocol.
Because PCoIP is UDP-based, this form of WAN acceleration is unnecessary.
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WAN accelerators also compress network traffic between client and server, but this compression is usually
limited to 2:1 compression ratios. PCoIP is able to provide compression ratios of up to 100:1 for images
and audio.
For information about the controls introduced with View 5 that you can use to adjust the way PCoIP consumes
bandwidth, see “Optimization Controls Available with PCoIP,” on page 48.
Bandwidth Requirements for Various Types of Users
When determining minimum bandwidth requirements for PCoIP, plan with the following estimates:
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100 to 150Kbps average bandwidth for a basic office productivity desktop: typical office applications with
no video, no 3D graphics, and the default Windows and VMware View settings.
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50 to 100Kbps average bandwidth for an optimized office productivity desktop: typical office applications
with no video, no 3D graphics, with Windows desktop settings optimized and VMware View optimized.
VMware View Architecture Planning
48 VMware, Inc.