StormQoS is a QoS implementation based on Cisco DiffServ and QoS models that is emulated through a dedicated QoS Gateway. It classifies packets based on fields like source/destination IP, DSCP, protocol, and port and then marks them with a DSCP value. Packets are then sent to queues based on the priority set by the user, with three types of queues: priority queuing, custom queuing, and custom based weighted fair queuing (CBWFQ). StormQoS policies are defined through an XML script.