Cisco Model D9479 Gigabit QAM Modulator Installation Guide

 

78-740242-01 Rev B 

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Versions of QAM software prior to software version 2.3.5 inserted the PowerKEY 

Conditional Access (CA) descriptor into the PMT for unencrypted on-demand 

content. If the Digital Home Communications 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 

Messages (ECMs) by waiting until an ECM was processed before allowing any other 

CA messages or requests to be processed. 

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. 

QAM software version 2.5.1 carries forward the modification from QAM software 

version 2.3.5 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 Multi-Room DVR sessions) to be 

established correctly on a Multi-Room server.