Refer to the exhibit.

In Quality of Service (QoS) for networking, Class of Service (COS) and Differentiated Services Code Point (DSCP) are used for traffic classification and prioritization. Voice traffic is generally given high priority due to its sensitivity to delay and requires proper tagging to maintain quality over the network.

The correct mapping for voice traffic, according to best practices, is a COS value of 5 mapped to a DSCP value of 46. This is because DSCP 46 corresponds to Expedited Forwarding (EF), which is typically used for voice traffic prioritization in IP networks.

The exhibit shows the output from a command on a network device that displays the current mappings between COS values and DSCP values. The mapping that needs modification for correct voice traffic tagging can be identified by looking at the standard practice for voice QoS, which uses a COS value of 5 mapped to a DSCP value of 46.

References := ( CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide )