Use a QoS policy rule to define traffic to receive QoS treatment (either preferential treatment or bandwidth-limiting) and assigns such traffic a QoS class of service.
Define a QoS policy rule to match to traffic based on:
Applications and application groups. Source zones, source addresses, and source users. Destination zones and destination addresses. Services and service groups limited to specific TCP and/or UDP port numbers. URL categories, including custom URL categories. Differentiated Services Code Point (DSCP) and Type of Service (ToS) values, which are used to indicate the level of service requested for traffic, such as high priority or best effort delivery.
Set up multiple QoS policy rules ( Policies > QoS) to associate different types of traffic with different QoS Classes of service.

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