Cisco DNA center Fabric QOS overview

Fabric QoS will be enforced through DNAC.  DNA Center takes all the configured QoS parameters and translates them into the proper device CLI commands. When you deploy the policy, DNA Center configures these commands on the devices defined in the site scope.  

The default QoS trust and queuing settings in application policies are based on the Cisco Validated Design (CVD) for Enterprise Medianet Quality of Service Design. CVDs provide the foundation for systems design based on common use cases or current engineering system priorities. 

Fig 1.1- Cisco SDA in a Box 

They incorporate a broad set of technologies, features, and applications to address customer needs. Each one has been comprehensively tested and documented by Cisco engineers to ensure faster, more reliable, and fully predictable deployment.  


Fabric QoS will be implemented with wireless QoS and wired QoS.  Wireless QoS will be based on Cisco Wireless AVC (Application Visibility Control) and apply to each SSID. Wired QoS will be based IOS-XE NBAR2 technologies and apply to all switches in each site.  


The default SDA QoS classification, marking and queuing policy will be used along with the known application marking.   

Cisco DNA Center bases its marking, queuing, and dropping treatments on IETF RFC 4594 and the business relevance category that you have assigned to the application. 

Cisco DNA Center assigns all of the applications in the Default category to the Default Forwarding application class and all of the applications in the Irrelevant Business category to the Scavenger application class. 

For applications in the Relevant Business category, Cisco DNA Center assigns traffic classes to applications based on the type of application. The following table lists the application classes and their treatments.  

The following steps will be used to create application policies

  1. Create an application policy with application set – this will use wireless AVC and IOS-XE NBAR2 to classify business relevant critical application with the correct marking.   
  2. Deploy an application policy with site scope – this will get SDA QoS policy applied to the site. 

QOS policy handover to Service Provider
SDA Service provider (SP) profiles define the class of service for a particular WAN provider.  4-class, 5-class, 6-class, and 8-class models can be used.  

When application policies are deployed on the devices, each SP profile is assigned a certain service-level agreement (SLA) that maps each SP class to a DSCP value and a percentage of bandwidth allocation