Question

A network engineer is reviewing the QoS policy on an enterprise WAN aggregation router. A running-config excerpt shows: 'class-map match-all VOICE / match dscp ef'. During troubleshooting, voice packets arriving from an access switch are marked with DSCP value 46, but the engineer notices some voice traffic is not matching the VOICE class. Which statement correctly explains the relationship between the DSCP marking and the class-map match criteria?

Accepted Answer

DSCP EF corresponds to the decimal value 46, so correctly marked voice packets should match; unmatched packets are likely marked with a different value such as CS5 (40).

Answer

DSCP EF corresponds to the decimal value 34, so packets marked 46 will never match the class-map.

Answer

DSCP EF corresponds to the decimal value 40, so only packets remarked to 40 by the access switch will match the class.

Answer

DSCP EF is a Layer 2 CoS value and cannot be matched against DSCP; the class-map must use 'match cos 5' instead.