At the highest level, QoS policy is considered as the component of QoS feature.
QoS policy — QoS is basically about classifying your network traffic and then giving it a preferential treatment accordingly. For example, it can involve classifying the traffic that is critical to your business operations and provide this class of traffic the highest preference in your network. To enable the Sensor to classify traffic, you define a set of rules that are similar to Firewall access rules. A QoS rule contains a set of criteria. The Sensor matches the detected traffic against these rules. So, it is possible to match all the traffic to be added to a specific QoS rule.
Similar to how a Firewall policy contains the Firewall access rules, a QoS policy contains the QoS rules. A QoS policy contains separate sets of QoS rules for each of the traffic management techniques - DiffServ tagging and IEEE 802.1p (VLAN) tagging.
Types of QoS policies — Two types of QoS policies are available in Trellix IPS. They are advanced and classic QoS policies. Functionally, these two types are similar. However, as the names may suggest, advanced QoS policies provide you more options to identify traffic when compared to classic.
Note
None of the NS-series or Virtual IPS Sensor models supports traffic management.