NAB Show Magazine Submission By Dan Fogel, Chief Technology Officer – DNF Controls
Broadcast facilities have varying needs, depending on size, affiliations, program types, and degree of playout automation. One constant is the all-important revenue producing commercial break; however, those audible “Break Start” and “Break End” signals of old are now silent commands sent to a Digital Program Inserter (DPI) – sometimes known as Digital Ad Insertion (DAI) – embedded among thousands of data bits and packets in the content stream.
Nevertheless, time is money and every commercial break counts. So how can the operator be certain those signals were sent; that a “Break Start” occurred at the correct time; that “Break Start” and “Break End” weren’t inadvertently reversed? The answer, of course, is a DPI Monitoring System to provide real-time oversight and logging of SCTE 104, SCTE 35, and other critical signals with immediate notification - by email, monitor wall alerts, visual cues, and other means - of late, missing or incorrect signals in the outbound or inbound video streams under its management.
So, what to look for in a DPI signal monitoring system? It depends on the facility’s mission and mode of operation. Here are some typical scenarios:
The Automated Facility:
No live programming, just scheduled playout under automation control for multiple network feeds the facility originates for distribution via satellite and cable.
An ideal system for this facility receives the daily automation playlists and checks for the presence of each DPI event at its scheduled time throughout the broadcast day. At minimum, it should:
About Dan Fogel:
Dan Fogel is founder and chief technology officer of DNF Controls. The award-winning company, founded in 1990, is a leading developer and provider of Human-to-Machine and Machine-to-Machine interfaces.
The Automated Facility:
No live programming, just scheduled playout under automation control for multiple network feeds the facility originates for distribution via satellite and cable.
An ideal system for this facility receives the daily automation playlists and checks for the presence of each DPI event at its scheduled time throughout the broadcast day. At minimum, it should:
- Monitor for the presence of a DPI event at a predefined point immediately before and after its scheduled time.
- Notify the operator of a LATE EVENT error – by a visual cue on the monitoring screen, e-messaging, and/or a multi-viewer screen notification – if the DPI event occurs after the predefined time window.
- Alert the operator of a MISSED EVENT error or a DPI TIMEOUT error if no DPI event is received within the allotted timeframe.
- Also, report a DPI SEQUENCE error for any interruption in the Break Start, Break End sequence.
- Reporting when critical signals are not received over a predefined time interval, in addition to reporting successful commercial Break Start and Stop events.
- An operator’s viewing screen to monitor the status of critical signals, both as they occur and to visually flag any errors. It should provide adequate flexibility for one operator to oversee multiple streams or several users to select and monitor various streams from their user interface.
- Letting operators view the events for a specific network or for all the networks they’re assigned to monitor.
- During periods of automated playout, the monitoring system should check every received DPI event to confirm it’s on-time and is of the correct type based on the scheduled playlist.
- During live content, the monitoring system reports when a commercial break starts and stops.
- In both operating modes, the system must report an error if expected DPI signals are not detected within a predefined timeframe.

