Setting up AES67 stream prioritization for Power Core redundant paths
Australian broadcasters have steadily moved away from traditional TDM routing toward standards-based IP audio, and AES67 sits at the centre of that shift. The standard gives radio operations in Sydney, Melbourne and Brisbane a way to move uncompressed audio between consoles, audio nodes and playout systems over the same network fabric, without locking into a single proprietary ecosystem. For organisations like the ABC, SBS, and commercial groups operating Triple J, Nova and ARN stations, this flexibility is invaluable when studios are spread across multiple floors or even buildings.
Redundant audio paths are no longer a luxury for radio professionals. A packet drop or switch reboot in a regional station in Perth or Adelaide can take a presenter off-air during drive time, and the reputational damage adds up quickly. AES67 supports primary and secondary streams, but the way a device prioritises them determines whether failover feels seamless or produces an audible glitch.
Power Core, Lawo's compact audio engine for radio workflows, handles redundant AES67 streams intelligently. Built on the same processing backbone as larger Lawo consoles, it offers deterministic behaviour for primary/secondary switching, load-balanced streaming and hitless merging. Engineers configuring Power Core can tune these behaviours through the HOME management platform or VisTool to match the resilience profile their facility requires.
This walkthrough looks at how to configure stream prioritization for redundant paths on Power Core, from the underlying concepts through to a validation checklist suitable for studios operating under Australian broadcasting technical limits and ACMA tolerances.
Why AES67 redundancy matters in Australian radio facilities
The Australian broadcast landscape presents unique resilience challenges. A regional network spanning thousands of kilometres between Perth and Cairns depends on shared infrastructure, and a single fibre cut can isolate a transmitter site for hours. Even in capital cities, on-air studios in Melbourne's Southbank or Sydney's Ultimo rely on tightly scheduled content, where any audio dropout during a cricket or AFL broadcast results in listener complaints and potential regulatory attention.
ACMA's technical operating standards expect broadcasters to maintain service continuity, and the expectation is reflected in how networks like Southern Cross Austereo and ARN design their playout chains. Redundant AES67 streams give operators a way to satisfy that expectation without doubling every physical cable. The key is making sure devices downstream know which stream to trust first, and what to do when the preferred stream disappears.
Inside Power Core's stream prioritization engine
Three prioritization modes are available inside the node. Primary/Secondary switching hands the entire stream to the highest-ranked source and switches over only when that source fails. Load balancing distributes channels across both streams so that neither link carries the full payload, and Hitless merging combines both feeds into a single, validated output with no dropouts during a switch. Each mode has a clear operational fit, and choosing the right one shapes the broadcaster's experience across everything from news studios in Brisbane to talk-format studios in Adelaide.
Power Core exposes these settings through a clean interface within HOME. Engineers can assign a priority value to each incoming AES67 session, configure the switching threshold in milliseconds, and decide whether the node should fall back automatically or wait for operator approval. VisTool can mirror the same configuration on a touch-friendly panel for studio supervisors who want quick visual confirmation during a live shift, and the same settings follow the operator into the next session.
Configuring stream priority in HOME or VisTool
Begin by opening the Power Core node in HOME and navigating to the AES67 I/O panel. Each stream appears as a logical input, with its source IP, multicast address and current status visible. Assign a numeric priority to the primary stream — lower numbers carry higher priority — then assign the secondary stream a higher value. For a studio where both feeds originate from the same playout server, load balancing is often the cleaner choice because it doubles available bandwidth and reduces per-link load.
Operators documenting their configuration across multiple sites may also reference a broadcast resource directory for templates and shared best practices, particularly when running parallel rollouts in Adelaide and Perth studios. Save the configuration and push it to the node. VisTool can be configured to display the live state of each stream, with colour cues showing which feed is currently active and a warning panel if both streams fail simultaneously.
PTP, QoS and network backbone considerations
Stream prioritization is only as reliable as the underlying network. Power Core requires PTP to be properly distributed across the AES67 VLAN, ideally from a grandmaster located close to the core switch. In Australian deployments where studios share infrastructure with corporate IT, putting AES67 on its own VLAN and tagging it with DSCP EF for expedited handling is essential. QoS settings on Cisco, Arista and Juniper switches should be consistent end-to-end, otherwise a switch in the chain can reorder packets and force Power Core to drop the affected stream.
Watch for asymmetric routing as well. If the primary and secondary AES67 streams traverse different physical paths, make sure both paths have similar latency profiles. A 40-millisecond skew between feeds is enough to confuse some merging algorithms, particularly when the studio is contributing to a statewide networked program originating from Sydney.
Validating failover in real scenarios
Validation should reflect the worst-case situations a station might face. Simulate a primary switch failure by pulling the SFP on the primary feed and timing how quickly Power Core promotes the secondary stream. For Hitless merging, capture both feeds simultaneously on a Wireshark trace and confirm the output remains continuous during the switchover. A live test from an off-site studio in Parramatta or a remote link from a mine site in the Pilbara gives engineers confidence the configuration survives jitter, packet loss and elevated latency.
A short regression test on the next morning's breakfast show is the real proof. Presenters notice audio quirks long before monitoring dashboards do, so a clean shift under live conditions is the strongest signal that prioritization is tuned correctly.
| Mode | Behaviour | Best fit | Configuration tip |
|---|---|---|---|
| Primary/Secondary switching | Promotes secondary only when primary fails | News, talk, single-host studios | Set switch threshold to 5 ms |
| Load balancing | Splits channels across both streams | High-channel-count playout, music formats | Match channel count per stream |
| Hitless merging | Combines both feeds into a single validated output | Live sport, networked programs | Verify PTP alignment before enabling |
Keep three points in focus when planning a redundant Power Core deployment: prioritise streams deliberately, validate against real failure scenarios rather than ideal conditions, and treat PTP and QoS as inseparable from the audio configuration itself. Australian facilities that respect these three points keep their presenters on the air and their audiences listening.
