Cisco Cisco Digital Service Access Node (DSAN) 8210 Troubleshooting Guide

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Emergency Alert System Support 
 
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Emergency Alert System Support 
This section describes the Emergency Alert System (EAS) support and operation for 
the DSAN device. 
Distribution and Triggering 
The DSAN unit supports EAS signaling via the SCTE-18 standard. The signaling is 
distributed to the DSAN device via a broadcast DOCSIS
®
 DSG Tunnel that is 
configured on the CMTS. The DSAN unit continuously monitors this tunnel for 
SCTE-18 data to trigger an emergency event. The unit determines the appropriate 
tunnel for the events through the processing of the DOCSIS Downstream Channel 
Descriptor (DCD). 
Notification Method 
The DSAN unit supports EAS notification via force tuning of specified output 
channels to a particular details channel. The details channel is specified in the SCTE-
18 data in the details_OOB_Source_ID parameter. Scrolling text and audio overlay are 
not supported due to the complexities of insertion to a high number of analog output 
channels by the device. 
Typical provisioning of the DSAN device should include the details channel as one 
of the 82 existing provisioned services on the output. In the event that the details 
channel is not a provisioned service, the unit will attempt to move an input tuner 
and demodulator to the appropriate carrier to process the details channel, and all 
provisioned output channels will be force-tuned to the details channel, as no 
guarantee can be made that exception channels can be supported. It should be noted 
that this reconfiguration of internal tuners and demodulators may result in 
temporary interruption of services going into and out of the EAS event. 
Exception Channel Handling 
To support exception channels, the details channel has to be one of the 82 existing 
provisioned services on the output. Exemptions to force tuning may be specified by 
including exception_OOB_Source_ID parameters for the sources that wish to be 
excluded. As the System Information (SI) data is carried out-of-band (OOB) for the 
DSAN device, the exception_major_channel_number and 
exception_minor_channel_number parameters are not used to determine exception 
channels per SCTE-18 specification.