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CA Descriptor and VOD Sessions
4023372 Rev B
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CA Descriptor and VOD Sessions
Overview
Versions of MQAM software prior to software version 2.5 inserted the PowerKEY
Conditional Access (CA) descriptor into the Program Map Table (PMT) for
unencrypted on-demand content. If the Digital Home Communication Terminal
(DHCT) operating system (OS) found the CA descriptor in the PMT, the OS started
the PowerKEY decryptor.
The PowerKEY scheduler within the DHCT then prioritized entitlement control
The PowerKEY scheduler within the DHCT then prioritized entitlement control
messages (ECMs) by waiting until an ECM was processed before allowing any other
CA messages or requests to be processed.
Background
During this waiting period, when no ECMs were delivered, non-ECM requests (for
example, a request for a Multi-Room DVR session) remained in the queue and were
not processed until the PowerKEY decryptor was stopped. Therefore, no Multi-
Room DVR sessions could be established while the Multi-Room DVR server was
streaming unencrypted VOD.
Solution
MQAM 2.6.18 carries forward the modification from MQAM 2.4.10 to insert the CA
descriptor only for encrypted sessions, including those that will be encrypted after
interactive session key (ISK) setup. Consequently, the OS now correctly detects the
encryption status of the stream. Detecting the encryption status enables sessions
(including VOD and MR-DVR sessions) to be established correctly on a Multi-Room
server.