Only based on the Cisco IOS XR policy-map configuration exhibit,
which statement is correct?
A.
All DSCP AF41 marked packets will be dropped when the average queue length reaches
12,000 packets.
B.
DSCP AF11 marked packets will be randomly dropped when the average queue length reaches
10,000 packets.
C.
DSCP AF11 and AF41 marked packets are guaranteed a minimum bandwidth of 1 Mb/s.
D.
DSCP AF11 and AF41 marked packets are guaranteed a maximum bandwidth of 1 Mb/s.
Explanation:
defining multiple curves effectively enables WRED for the traffic class – random-detect [marker] [marker-value] [min] [max]; for XR, applied in input or output direction; threshold units: packets, kb, mb, gb, milli- or microseconds
WRED can use multiple different RED profiles – drops less important packets more aggressively than important packets; performs differentiated packet dropping based on packet markers, DSCP; monitors queue length and determines when to discard packets based on length of the interface queue; WRED only useful when the bulk of the traffic is TCP b/c the packet source reduces its transmission rate when dropped packets indicate congestion; WRED used more often in the core than in the edge and access networks
http://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/command/reference/fqos_r/qrfcmd1.html#wp1083571
You can configure the bandwidth command when either the queue-limit or the random-detect command is configured in a class policy. The bandwidth command specifies the amount of bandwidth allocated for the class.
http://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/configuration/guide/fqos_c/qcfwred.html#wp1002342
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Not answer A because class test may be matching on specific traffic; not ALL traffic.