5.3

Manage Access to Windows 7 Multimedia Redirection
You can take steps to ensure that Windows 7 Multimedia Redirection (MMR) is accessible only to View
Client systems that have appropriate resources and that are connected to Horizon View on a secure
network.
MMR data is sent across the network without application-based encryption and might contain sensitive
data, depending on the content being redirected. To ensure that this data cannot be monitored on the
network, use MMR only on a secure network.
You might want to disable MMR if client systems have insufficient resources to handle local multimedia
decoding or if you want to restrict access to MMR only to client systems on a secure network. You can
configure a policy in View Administrator, Multimedia redirection (MMR), that lets you disable or enable
MMR for client systems. You can set the policy globally, for specific desktop pools, or for specific users. The
policy is enabled by default. The policy affects MMR for Windows 7, Windows XP, and Windows Vista
desktops. For details, see “Configuring Policies” in the VMware Horizon View Administration document.
Ensure That Clients Can Initiate Windows 7 MMR
Windows 7 MMR uses a handshake between the Horizon View Client system and the desktop to validate
requests for multimedia redirection. Under certain network conditions, this handshake can take too long to
complete, which causes MMR not to be initiated. To ensure that Windows 7 MMR can be initiated, you can
configure a Windows registry key on the desktop to increase the time allowed for the validation handshake
to complete.
The Windows registry key controls the handshake Time to Live (TTL) value and is set in milliseconds. The
key is in REG_DWORD (hex) format. The default value is 5000 milliseconds (five seconds).
Before you deploy Windows 7 MMR to your Horizon View users, test a few client systems to check if the
default time allowed to complete the handshake is adequate in your environment. If your network
conditions require a longer handshake than five seconds, increase the TTL value.
Procedure
1 Start the Windows Registry Editor on the virtual desktop.
2 Navigate to the Windows registry key that controls the MMR validation handshake.
Option Description
Windows 7 64-bit
HKEY_LOCAL_MACHINE\Software\Wow6432Node\VMware,Inc.\VMware
VDPService\handshakeTTL
Windows 7 32-bit
HKEY_LOCAL_MACHINE\Software\VMware,Inc.\VMware
VDPService\handshakeTTL
3 Increase the handshakeTTL value to a number that is greater than 5000.
4 Restart Windows Media Player on the desktop to allow the updated value to take effect.
VMware Horizon View Feature Pack Installation and Administration
40 VMware, Inc.