Polycom VS4000 User Manual

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Integrators’ Reference Manual for ViewStation EX, ViewStation FX, and VS4000
44
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Crypto Resync
If a cryptographic encoder/decoder is connected between the 
system and the network, it may require a resynchronization signal 
from the system. This is a signal indicating that the system has lost 
video synchronization due to a network problem and requires that 
the cryptographic encoder/decoder resync with the equipment at 
the other end of the connection.
To use this feature, select System Info > Admin Setup > Security
When you select the Crypto Resync option, the Crypto Resync 
Pulse 
screen appears. 
On this screen you can enable crypto resync, set the time between 
pulses (in seconds), and set the pulse width (in milliseconds). 
If the system loses H.320 synchronization while in a call, it sends the 
resynchronization pulses at the specified rate until H.320 regains 
synchronization. 
The resync pulse is output on the RTS signal. If this feature is 
enabled, the RTS signal no longer functions as the Ready-To-Send 
signal. 
Most installations that use encryption equipment require a custom 
cable. The cable should route the RTS signal from the system to the 
appropriate resync input on the encryption equipment. The 
encryption equipment can get its RTS input from the 
videoconferencing system's DTR output or by tying this input high. 
In this non-dialed mode, the DTR output and RTS output act alike.