Cisco DTA Control System (DTACS) 1.2 Betriebsanweisung

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Chapter 7    Emergency Alert System 
 
 
 
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EAS With the DTACS 
The DNCS generates in-band EAS messages on every QAM that carries at least one 
unencrypted service. 
EAS messages are received by an EAS receiver, which sends all EAS messages 
directly to the DNCS. The DNCS receives the EAS messages and forwards them to 
the out-of-band modulators, for the benefit of legacy devices.   
The DNCS also forwards the EAS messages to each enabled QAM for the benefit of 
clear QAM tuners. The QAMs multiplex the EAS messages into the in-band 
transport stream. The DTA uses the in-band EAS facility of the DNCS. 
The DNCS enables in-band EAS based on the "Default Host" channel map. Any 
QAM that carries one or more clear services, as listed in the "Default Host" channel 
map, also carries in-band EAS messages.  
Note: The Default Host channel map is different from the "Default" channel map. 
The Default Host channel map must be enabled for EAS to work with the DTACS.