Refer to the exhibit. Your company’s QoS policy states that all traffic that is arriving at access layer
switches from IP phones should be marked with a DSCP value of 46 and that all untagged traffic
that is arriving from a PC that is attached to an IP phone should be marked with a CoS value of 1.
Which two options will satisfy the 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
Explanation:
To define the ingress Class of Service (CoS)-to-differentiated services code point (DSCP) map for
trusted interfaces, 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 that
correspond to CoS values 0to 7. Separate consecutive DSCP values from each other with a
space. The supported DSCP values are 0, 8, 10, 16, 18, 24, 26, 32, 34, 40, 46, 48, and 56.
To define the default multilayer switching (MLS) class of service (CoS) value of a port or to assign
the default CoS value to all incoming 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, the default CoS value is used to select one output queue as an index into the CoS-toDSCP map. The CoS range is 0 to 7. The default is 0.
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