A read-write setting selecting the queue scheduling algorithm for this specific port: strict priority (sp), weighted round robin (wrr), a combination of both (spWrr), or weighted fair queueing (wfp). This is the per-port counterpart to deviceBaseQosPolicyMode, letting an admin apply a different scheduling algorithm on individual ports when qosGlobalSetMode is set to portBased, rather than a single device-wide scheduling mode. An admin might set a port carrying latency-sensitive voice traffic to sp so voice queues always drain first, while leaving a bulk-data port on wrr for proportional bandwidth sharing.