Refer to the exhibit. Your company’s QoS policy states that all traffic that is arriving at access layer switchesfrom IP phones should be marked with a DSCP value of 46 and that all untagged traffic that is arriving froma PC that is attached to an IP phone should be marked with a CoS value of 1. Which two options will satisfythe requirements for the CoS-to-DSCP map and are the correct QoS commands? (Choose two.)
A. mls qos 1
B. mls qos map cos-dscp 0 10 18 26 34 46 48 56
C. mls qos cos 1
D. mls qos map dscp 0 8 16 26 32 40 48 56
E. mls qos map cos 0 8 18 26 40 48 50 56
F. mls qos dscp 1
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Cisco 642-437 Exam
Correct Answer: BC
Explanation/Reference:
Explanation: To define the ingress Class of Service (CoS)-to-differentiated services code point (DSCP) map for trustedinterfaces, use the mls qos map cos-dscp command in global configuration mode.
mls qos map cos-dscp dscp1…dscp8
dscp1…dscp8 – Defines the CoS-to-DSCP map. For dscp1…dscp8, enter eight DSCP values thatcorrespond to CoS values 0to 7. Separate consecutive DSCP values from each other with a space. Thesupported DSCP values are 0, 8, 10, 16, 18, 24, 26, 32, 34, 40, 46, 48, and 56. To define the defaultmultilayer switching (MLS) class of service (CoS) value of a port or to assign the default CoS value to allincoming packets on the port, use the mls qos cos command in interface configuration mode.
mls qos cos cos-value
cos-value – Assigns a default CoS value to a port. If the port is CoS trusted and packets are untagged, thedefault CoS value is used to select one output queue as an index into the CoS-to- DSCP map. The CoSrange is 0 to 7. The default is 0.
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