Question

When is a flow categorized with QOS priority 255, even though there is no network rule to assign this priority?

Answer

QoS priority 255 is referred to as the Default priority in the BW Management window (Networking > BW Management).

There are several reasons why a flow can be assigned QoS priority 255:

• Cato evaluates the network profile for each flow, and the QoS priority is assigned when the flow is identified with a specific application.
  • The first packets (before the flow is identified) are assigned QoS priority 255.
  • As long as the application for a flow isn't identified, then the flow is assigned QoS priority 255 and is shown in the Analytics windows with that priority.
• Blocked flows are assigned QoS priority 255.
• Traffic that is redirected from a block page is assigned QoS priority 255. For example, when someone tries to go to a compromised website that is blocked by IPS.