With Quality of Service (QoS), you can prioritize business-critical traffic and applications that require low latency (like VoIP and video applications).To add or edit a QoS policy rule, go to ManageConfigurationNGFW and Prisma AccessNetwork PoliciesQoS.

Quality of Service (QoS) policy rules to identify traffic that requires preferential treatment or bandwidth limiting. QoS rules allow you to dependably run high-priority applications and traffic under limited network capacity. You can configure traffic QoS treatment using the Differentiated Services Code Points (DSCP). These codepoints are packet header values that can be used to request (for example) high priority or best effort delivery for traffic. Prisma Access both enforces DSCP values for incoming traffic and marks a session with a DSCP value as session traffic exits the firewall. This means that all inbound and outbound traffic for a session is receiving continuous QoS treatment. You can configure traffic QoS treatment using the following codepoints:

• Expedited Forwarding (EF)—Used to request low loss, low latency and guaranteed bandwidth for traffic.
  Packets with EF codepoint values are typically guaranteed highest priority delivery.
• Assured Forwarding (AF)—Used to provide reliable delivery for applications.
  Packets with AF codepoints indicate a request for traffic to receive higher priority treatment than best effort service provides. Packets with EF codepoint take precedence over packets with AF codepoint.
• Class Selector (CS)—Used to provide backwards compatibility with network IP addresses that use the IP precedence field to mark priority traffic.
• IP Precedence (ToS)—Used by legacy network IP addresses to mark priority traffic.
• Custom Codepoint—Create a custom codepoint to match traffic by entering a Codepoint Name and Binary Value.
  For example, you can create a QoS policy rule to prioritize voice communications, such as voice over IP (VOIP), to ensure consistent packet transmission. This ensures that voice communication are consistent.