Example LLQ Example on the Enterprise WAN Edge Router

policy-map WAN-EDGE class ROUTING

bandwidth percent 3 class VOICE

priority percent 18 class VIDEO-CONF

priority percent 15 class STREAM-VIDEO bandwidth percent 10

class-map match-all ROUTING

match ip dscp cs6 class-map match-all VOICE

match ip dscp ef class-map match-all VIDEO-CONF

match ip dscp af41 class-map match-all STREAM-VIDEO

match ip dscp cs4 class-map match-all MISSION-CRIT

match ip dscp 25 class-map match-any VOICE-CONTROL match ip dscp cs3 match ip dscp af31 class-map match-all TRANSACT

match ip dscp af21 class-map match-all NETWORK-MGMT

match ip dscp cs2 class-map match-all BULK

match ip dscp af11 class-map match-all SCAVENGER match ip dscp cs1

policy-map WAN-EDGE class ROUTING

bandwidth percent 3 class VOICE

priority percent 18 class VIDEO-CONF

priority percent 15 class STREAM-VIDEO bandwidth percent 10

class MISSION-CRIT bandwidth percent 12 random-detect dscp-based class VOICE-CONTROL bandwidth percent 2

class TRANSACT

bandwidth percent 8 random-detect dscp-based class NETWORK-MGMT bandwidth percent 2

class BULK

bandwidth percent 4 random-detect dscp-based class SCAVENGER

bandwidth percent 1 class class-default bandwidth percent 25 random-detect dscp-based

If the default class is allocated a bandwidth, WFQ cannot be enabled for the traffic within the default class. This is true for all platforms except the Cisco 7500 (and soon the Cisco 7200).

The figure illustrates an example of an enterprise WAN-edge router configuration using LLQ with class-based WRED on certain data traffic classes.

This assumes the markings for the different traffic classes are already done at the access or at the distribution layer within the campus network.

Currently (except for the Cisco 7500 router platform) all traffic classes except for the default traffic class support only FIFO queuing within the class. Check http://www.cisco.com for the latest information on weighted fair queuing (WFQ) support within each traffic class.

On all platforms, the default traffic class can support either FIFO or WFQ within the class. But if the default traffic class is allocated a minimum bandwidth as shown in the figure, WFQ will not be supported in the default traffic class. The only current exception is for the Cisco 7500 series platforms. In this case, the default traffic class will support only FIFO queuing.

Note In this example, the maximum reservable bandwidth on the link is set to 0 percent, so that up to 100 percent of the link bandwidth can be guaranteed between the different classes.

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