Which egress QoS queue on a WAN Edge should be used for voice traffic?

Cisco SD-WAN QoS policies map traffic to specific queues based on DSCP values. By default, voice traffic (typically DSCP EF) is mapped to queue 0, which is the highest priority queue and is often configured for Low Latency Queuing (LLQ). This ensures voice packets receive preferential treatment, minimizing delay and jitter. Queues 1, 3, and 7 are typically used for other types of traffic, such as network control, critical data, or best-effort traffic, and do not offer the same priority as queue 0 for real-time applications like voice.