Cisco Systems QC-29 Manual De Usuario

Congestion management controls congestion after it has occurred on a network. Congestion can be 
managed on Cisco IOS XR software by using packet queueing methods, and by shaping the packet flow 
through use of traffic regulation mechanisms.

Packet queueing methods define packet scheduling or the order in which packets are dequeued to the 
interface for transmission on the physical wire. Furthermore, queueing methods support minimum 
bandwidth guarantees and low latencies based on the order and number of times that a queue is serviced.

The following types of queueing methods and traffic regulation mechanisms are supported on the 
Cisco IOS XR software:

Modified Deficit Round Robin (MDRR)

Low-latency queueing (LLQ) with strict priority queueing (PQ)

Traffic shaping

Traffic policing

This module provides the conceptual and configuration information for Quality of Service (QoS) packet 
queueing methods and traffic regulation mechanisms on Cisco IOS XR software.

For additional conceptual information about QoS in general and complete descriptions of the QoS 
commands listed in this module, see the 

 section of this module. To locate 

documentation for other commands that might appear in the course of executing a configuration task, 
search online in the Cisco IOS XR software master command index.