Exam 400-101 | Question id=1150 | Infrastructure Services |
You issue the show running-config command on a Cisco 3700 series router and receive the following partial output:
class-map match any kyiv
match ip precedence 3
match ip precedence 4
class-map match any exsim
match ip precedence 2
!
policy-map applications
class kyiv
priority 32
class exsim
bandwidth 16
class class-default
fair-queue
random-detect
Which of the following classes use FIFO queuing within the class?
A. |
only the kyiv class | |
B. |
only the kyiv and exsim classes | |
C. |
only the exsim and class-default classes | |
D. |
the kyiv, exsim, and class-default classes |
The kyiv and exsim classes use first-in-first-out (FIFO) queuing within the class. In this scenario, class-based weighted fair queuing (CBWFQ) and low latency queuing (LLQ) are used, as indicated by the priority and bandwidth commands. However, only the class-default class can use weighted fair queuing (WFQ); the other classes can use only FIFO queuing within the class. A traffic class may be prioritized over other traffic classes, but traffic within that class is processed in the order the traffic is received, without regard for packet type, protocol, or IP precedence. For example, traffic with an IP precedence value of 3 might be transmitted ahead of traffic with an IP precedence value of 4 even though its precedence value is lower.
Although the class-default class can use FIFO queuing, it is currently configured to use WFQ. The fair-queue command configures the class-default class to use WFQ queuing. To configure the class-default class to use FIFO queuing, you should issue the no fair-queue command.