Hdcp Management; Mixing Encrypted And Unencrypted Signals; Hdpc Key Caching; Avoiding Unnecessary Hdcp Encryption - Lightware UMX4x4-Pro2 User Manual

4.3. HDCP management

Lightware Visual Engineering is a legal HDCP adopter, and several functions have
developed which help to solve HDCP related problems.

4.3.1. Mixing encrypted and unencrypted signals

Complex AV systems often have both HDCP and non-HDCP components. Lightware
UMX matrices allow to use HDCP encrypted and unencrypted signals in the same
system.
The router will be still HDCP compliant as it will never output an encrypted signal to a
non-HDCP compliant display device. If an encrypted signal should be switched to a
non-compliant output, it will be muted.
Info: If an output is connected to an input and the output gets a valid video signal (external
video source or no screen screen) from the crosspoint, then the muting means the device
gives black screen. The resolution and refresh rate of the black screen is the same as the
incoming video. If there is no incoming video (via the crosspoint) muting results a missing
signal.

4.3.2. HDPC key caching

Lightware introduced the HDCP key cashing technique in early 2009 that validates all the
display keys in an AV system during system boot up and keeps them constantly available
for sources. This method eliminates the HDCP handshake at every switch and keeps all
sources sending uninterrupted signals.
Without this function the sources should re-authenticate HDCP after each crosspoint
switch which makes the displays to drop the signal and go black for 5-8 seconds. The
HDCP key cashing technique avoids this and allows instantaneous switching between
two encrypted signals.

4.3.3. Avoiding unnecessary HDCP encryption

Many video sources send HDCP protected signal if they detect that the sink is HDCP
capable – even if the content is not copyrighted. This can cause trouble if a HDCP
capable device (e.g. repeater or matrix router) is connected between the source and the
display. In this case the content can't be viewed on non-HDCP capable displays and
interfaces like event controllers.
Rental and staging technicians often complain about certain laptops, who always send
HDCP encrypted signals if the receiver device (display, matrix router, etc.) reports HDCP
compliancy. However, HDCP encryption is not required all the time (e.g. computer
desktop image) certain laptops still do that.
unprotected content
To
enabling/disabling function: the HDCP capability can be disabled on each input port
separately. If HDCP is disabled on an input port, the connected source will detect that the
sink is not HDCP capable, and turn off authentication. The source will not be able to
communicate with any of the devices (displays, repeaters, etc.) that are connected to the
routers output, therefore it could not see if they are HDCP capable or not.
Section 4. Technologies
encrypted signal
avoid unnecessary
HDCP compliant
repeater
HDCP encryption, Lightware
UMX4x4-Pro2
User's Manual
Non HDCP display
introduced the HDCP
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