As the transition towards IP-based workflows in broadcast and media infrastructures powers on, precise timing and reliable failover have become more critical than ever. A common challenge in hybrid and IP environments is ensuring that all timing references remain aligned during a failover event. With the introduction of synchronised operation for failover, this challenge can now be effectively addressed.
The Challenge: Reference Mismatch During Failover
In many systems, Precision Time Protocol (PTP) is used as the primary timing reference, while Black Burst (BB), Tri-Level Sync (TLS), and Digital Audio references are generated by separate devices or SPGs. During a failover, it is possible for PTP to switch to a new grandmaster while BB, TLS, and audio references continue to originate from a different SPG.
This condition, known as a Reference Mismatch, can lead to subtle but serious issues, including timing instability, loss of synchronization, and degraded system performance. In live broadcast environments, even brief inconsistencies can have visible or audible consequences.
Introducing Synchronised Operation for Failover
With Leader’s LT4670 SPG, synchronised operation for failover, ‘SyncAlign’, is now supported when used alongside its LT4448 changeover unit. SyncAlign ensures that all timing references switch together, maintaining complete system alignment during failover events.
Synchronised operation tightly couples the behaviour of the PTP reference with BB, TLS, and Digital Audio references. Rather than allowing each reference domain to change independently, the system now performs a fully coordinated changeover based on PTP priority.
How It Works
The key to this capability is the new LC2187 cable, which directly connects the Leader and Follower LT4670 units with the LT4448. This physical link enables real-time coordination between devices, ensuring that when PTP priority changes occur:
- The active PTP reference switches as expected
- BB, TLS, and Digital Audio references transition simultaneously
- All references originate from the same SPG after the changeover
The result is a clean, deterministic failover with no opportunity for reference divergence.
Benefits for Broadcast and Media Facilities
SyncAlign for failover delivers several important advantages:
- Elimination of Reference Mismatch
All timing domains always remain synchronized to the same source.
- Improved System Reliability
Coordinated failover reduces the risk of timing-related errors during critical events.
- Simplified System Design
Engineers no longer need to implement complex workarounds to manage reference switching.
- Confidence in Live Operations
Seamless transitions help protect on-air content and maintain signal integrity.
A Step Forward in Timing Resilience
As facilities increasingly rely on PTP-based architectures, ensuring consistent behaviour across all reference types is essential. SyncAlign represents a significant step forward, providing a robust and elegant solution to a long-standing synchronization challenge.
By combining the LT4670, LT4448, and LC2187 cable, engineers can now achieve fully aligned, priority-driven failover without compromise.