On Cisco and other vendor switches, IP telephony traffic can be assigned to higher priority queues. The number, sizes, and functioning of the queues is device dependent and beyond the scope of this document.

However, a fixed number of queues exist, and the queues are usually not configurable. Older or lower end switches have only two queues or none. Newer or higher-end switches commonly have four or eight queues, with eight being the maximum because there are only eight Layer 2 priority levels. When configured, the Ethernet switch can identify the high-priority traffic by the 802.1p/Q tag and assign that traffic to a high-priority queue. On some switches, a specific port can be designated as a high-priority port, which causes all traffic that originates from that port to be assigned to a high-priority queue.