Conditional Access
HE4000 Encoding System
Save the Current BISS Configuration
7.
Save the current BISS configuration to either:
•
Flash memory using the CM Save command.
•
A user-defined configuration set, using the cm create and
cm save_cfg commands.
Any parameter changes, including conditional access changes, that are made using a remote unit
are not automatically stored in flash memory. When the HE4000 configuration is changed using a
remote unit, an operational test should be performed to verify that the system is operating
correctly. Then the new configuration should be saved by issuing the cm save command.
If the HE4000 is reset, or looses power prior to issuing the cm save command, any changes
made using the remote unit will not be restored. Instead, the HE4000 restores the last changes
saved to flash memory. Once the configuration is saved using the cm save command, the
HE4000 automatically restores the saved settings when the unit is reset or powered up.
To Disable BISS
For a Service
Type CA BISS1 ENABLE OFF and press Enter. For BISS E type CA BISSE ENABLE OFF and
press Enter.
B.5 ComtechTV PGCA Overview
At the System Level
PGCA (Privacy Guard Conditional Access) is a ComtechTV-proprietary conditional access
scrambling system supported by all ComtechTV DVB-compatible encoders and decoders.
PGCA is a fixed key scrambling system that is addressable. This means that the scrambling key
is included in the transport stream, along with the list of individual decoder addresses authorized
to descramble the transmission.
Using PGCA allows the uplink to control which decoders are authorized to receive the
transmission, and what key is used to scramble the stream. The decoders automatically receive
and process the authorization list. If they are authorized to receive the transmission, they extract
the key and use it to descramble the service. If they are not authorized, they do not descramble
or decode the service, and there is no output of video or audio from the decoder.
Although this is a fixed key system, the addressability and in-band transmission of all information
required to authorize and descramble the service is very powerful for controlling groups of IRDs
and the services they are allowed to receive, without compromising the security by distributing the
scrambling key in the clear to the decoders. The “fixed” key is programmable and can be
changed by the uplink encoder operator if desired.
Managing the key and the decoder authorization list is simple to do using remote control
commands. No control computer or special software is necessary. PGCA is included in all
ComtechTV DVB-compliant encoders and decoders as a standard feature, so there are no
additional costs to use PGCA in a system.
There are two types of PGCA, HD PGCA and SD PGCA to individually assign encryption to either
service. Operationally the encoder stores two decoder authorization list (HD PGCA list and SD
PGCA list).
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