Dante QoS Settings: Prioritize Clock and Audio Traffic

TL;DR — Dante marks clock, audio, and other packets with DSCP values so a compatible switch can place time-critical traffic ahead of ordinary data. QoS is especially important on mixed-use, congested, mixed-speed, or video-carrying networks. Preserve Dante's markings, map them to four or more queues with clock highest and audio next, use strict priority where supported, then verify the actual switch policy, link load, errors, latency, and audio under a controlled stress test.

QoS decides which packets leave a busy link first

Quality of Service does not create bandwidth. It gives a managed switch rules for classifying queued packets and deciding which class transmits first when several packets compete for the same egress link.

Dante uses Differentiated Services Code Point (DSCP) markings in the IP header. The endpoint marks the traffic; the switch must trust or classify that marking and map it to an appropriate hardware queue.

Exact DSCP values and switch commands depend on the Dante mode, device generation, firmware, and switch platform. Use the current Audinate and switch-vendor documentation rather than copying an unverified template from another network.

Know when QoS matters

A small, dedicated gigabit Dante network with low utilization may pass audio correctly without a custom switch policy. That does not prove QoS is configured, and it does not predict behavior after more traffic is added.

QoS becomes important when the network has one or more of these conditions:

• Dante shares links with control, office, internet, file-transfer, NDI, or other data;
• Dante video or another high-bandwidth media system uses the same infrastructure;
• the path contains both 100 Mbps and gigabit links;
• uplinks aggregate traffic from several access switches;
• redundant or failover events can move traffic onto fewer links;
• the design intentionally operates near a link's practical capacity.

Priority cannot repair an oversubscribed design. If time-critical traffic alone exceeds a link's capacity, packets will still be lost. Fix the topology, link speed, multicast scope, or channel count before treating QoS as a substitute for capacity.

The Dante unicast versus multicast guide explains how receiver fanout changes flow and bandwidth behavior. QoS and multicast management solve different problems.

Translate Dante markings into switch queues

A useful Dante policy preserves the endpoint's DSCP markings and maps them consistently across every switch in the media path. Audinate recommends switches with DSCP-based QoS, at least four queues, and strict-priority queuing for relevant deployments.

Build the policy deliberately:

1. inventory every switch model, firmware version, port speed, and uplink;
2. confirm whether the switch trusts DSCP on access ports or rewrites it;
3. map Dante clock traffic to the highest-priority queue;
4. map time-critical Dante media to the next queue;
5. place control traffic below real-time media and ordinary data below that;
6. apply the policy consistently across the complete path;
7. save and export the accepted switch configuration.

Do not assume queue number 7 is always higher than queue number 1. Vendors label and schedule queues differently. Verify the scheduling behavior, not merely the interface name.

Keep clock and audio priorities distinct

Clock packets are small but highly sensitive to delay variation. Audio packets carry more bandwidth and also have a deadline. Giving clock the highest class helps preserve stable synchronization while audio receives the next real-time class.

The Dante clock leader guide covers leader election and external references. QoS protects packet delivery; it does not choose the leader or correct a bad clock design.

Treat custom DSCP changes as an advanced operation

Some Dante products expose PTPv2 DSCP settings for standards-based interoperability. Changing these values without an end-to-end plan can make the endpoints and switches disagree. Record the original values, the reason for the change, every affected device, and the rollback before editing them.

Remove network behaviors that work against real-time audio

QoS is only one part of a suitable switch configuration. Inspect the following boundaries as well:

• Energy Efficient Ethernet: disable EEE or Green Ethernet on Dante ports where the device and switch guidance requires it;
• link speed and duplex: confirm the negotiated state at every endpoint and uplink;
• multicast control: use IGMP snooping and a correctly placed querier when the network design requires them;
• storm control and rate limits: ensure they do not discard legitimate discovery, clock, or media traffic;
• VLAN and routing boundaries: keep the approved Dante path and discovery scope explicit;
• Wi-Fi: do not use wireless links to carry Dante media; isolate or filter multicast media from controller access points.

Avoid enabling a bundle of generic “voice VLAN” or automatic QoS features without understanding how they classify Dante. A preset designed for desk phones may rewrite markings or prioritize the wrong traffic.

Verify the policy under realistic load

1. Save a clean baseline

Record topology, switch configurations, device names, link speeds, sample rates, latency settings, subscriptions, multicast flows, and normal port utilization.

2. Inspect classification and counters

Confirm that packets with the expected markings enter the intended queues. Check interface errors, discards, queue drops, congestion counters, and uplink utilization on every relevant switch.

3. Test the real audio destinations

Listen and meter at consoles, processors, amplifiers, recorders, and broadcast outputs. A switch counter alone cannot prove channel identity or end-to-end audio.

4. Add controlled competing traffic

During an authorized test window, reproduce the highest credible data load without exceeding the approved design. Watch clock stability, receive latency, packet errors, queue drops, and audible output.

5. Test failure paths

Remove one uplink or approved network component at a time. Confirm that the remaining path has enough capacity and preserves the same QoS policy. The Dante latency settings guide explains why raising the receive buffer should follow path diagnosis rather than replace it.

6. Restore and compare

Return the network to the accepted topology, verify every route, and compare counters with the baseline. Save the final configuration and date the evidence.

Put network priority ownership in the Rider

A useful handoff names the Dante VLAN or physical network, switch models and owners, DSCP trust boundary, queue mapping, scheduling mode, EEE state, link speeds, uplinks, multicast policy, normal utilization, stress-test method, failure test, monitoring access, and rollback file.

In Techrider.live, align network device names with the I/O and equipment lists, invite the system and network engineers to edit the same Rider, save the accepted switch plan, inspect history after a change, and export a dated PDF for load-in.

Dante QoS checklist

• Every switch and link in the Dante path is inventoried.
• Dante DSCP markings are trusted or classified intentionally.
• Clock has the highest real-time priority and media the next.
• At least four queues and the scheduling behavior are verified.
• EEE, link speed, multicast, VLAN, and rate-limit settings are checked.
• Queue counters and real audio destinations are tested under load.
• Failure paths, rollback, and configuration ownership are documented.

FAQ

Does Dante require QoS?

Not every small dedicated network needs a custom QoS configuration to pass audio, but QoS is important on mixed-use, congested, mixed-speed, or video-carrying networks. Design it before utilization or topology makes packet competition visible as a fault.

What QoS settings does Dante use?

Dante endpoints mark traffic with DSCP values for clock, time-critical media, control, and best-effort classes. The switch must preserve or classify those markings and map them to appropriate queues. Confirm current values in the relevant Audinate documentation.

Should Dante QoS use strict priority queues?

Audinate recommends DSCP-based QoS with four queues and strict-priority queuing for suitable Dante networks. Confirm the switch vendor's queue order and starvation protections before applying the policy.

How do you verify QoS on a Dante network?

Inspect DSCP classification, queue mappings, port and queue counters, link utilization, clock stability, latency, and errors. Then test the real audio destinations under a controlled competing load and approved failure conditions.

Can Dante share a network with other traffic?

Yes, when capacity, QoS, multicast control, VLAN or routing boundaries, and operational ownership are designed end to end. Sharing a switch does not automatically mean every path has enough bandwidth or consistent priority.

Make packet priority testable

Create one Rider that records the traffic classes, trust boundary, queue policy, link capacity, monitoring, stress test, failure test, owner, and rollback before the show depends on the network.