nerdexam
Cisco

350-001 · Question #148

Modified deficit round robin supports which of these functionalities?

The correct answer is A. priority queue C. round-robin service of output queues. Modified deficit round robin (MDRR)--MDRR, a traffic class prioritization mechanism used only on GSR platforms, incorporates emission priority as a facet of quality of service. MDRR is similar in function to WFQ on non-GSR platforms. In MDRR, IP traffic is mapped to different…

QoS

Question

Modified deficit round robin supports which of these functionalities?

Options

  • Apriority queue
  • Bweighted fair queues
  • Cround-robin service of output queues
  • DLLQ

How the community answered

(40 responses)
  • A
    93% (37)
  • B
    3% (1)
  • D
    5% (2)

Explanation

Modified deficit round robin (MDRR)--MDRR, a traffic class prioritization mechanism used only on GSR platforms, incorporates emission priority as a facet of quality of service. MDRR is similar in function to WFQ on non-GSR platforms. In MDRR, IP traffic is mapped to different classes of service queues. A group of queues is assigned to each traffic destination. On the transmit side of the platform, a group of queues is defined on a per- interface basis; on the receive side of the platform, a group of queues is defined on a per-destination basis. IP packets are then mapped to these queues, based on their IP precedence value. These queues are serviced on a round-robin basis, except for a queue that has been defined to run in either of two ways: a) strict priority mode, or b) alternate priority mode. In strict priority mode, the high priority queue is serviced whenever it is not empty; this ensures the lowest possible delay for high priority traffic. In this mode, however, the possibility exists that other traffic might not be serviced for long periods of time if the high priority queue is consuming most of the available bandwidth. In alternate priority mode, the traffic queues are serviced in turn, alternating between the high priority queue and the remaining queues.

Topics

#MDRR#priority queue#round-robin queuing#output scheduling

Community Discussion

No community discussion yet for this question.

Full 350-001 Practice