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Cisco AVVID Network Infrastructure Enterprise Quality of Service Design
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Chapter 4 QoS in an AVVID-Enabled Wide-Area Network
QoS Recommendations for WAN Aggregation Routers
Tip
For more information on the percent keyword, see Low Latency Queueing with Priority Percentage
Support.
In the following configuration for voice only over a T1 link:
·
Voice is assigned to an LLQ.
·
Voice control traffic is guaranteed.
·
All non-voice traffic is assigned to a default queue to receive weighted-fair queueing.
class-map match-all VOICE
match ip dscp ef
!
class-map match-all VOICE-CONTROL
match ip dscp af31
!
!
policy-map WAN-EDGE
class VOICE
priority percent 33
class VOICE-CONTROL
bandwidth percent 2
class class-default
fair-queue
Or:
class-map match-all VOICE
match ip dscp ef
!
class-map match-all VOICE-CONTROL
match ip dscp af31
!
!
policy-map WAN-EDGE
class VOICE
priority 506
class VOICE-CONTROL
bandwidth percent 2 or bandwidth 30
class class-default
fair-queue
DSCP keywords and decimal values are completely synonymous (DSCP EF is the exactly the same as
DSCP 46). Both refer to a value of 101110 in the first 6 bits of the ToS byte.
Note
At the time of writing, IOS 12.2(8)T converts DSCP keywords to their decimal equivalents in the
running configuration.
Note
Remember that this policy does not take effect until it is bound to an interface with a service-policy
statement. Service-policy statements are discussed in the
section.
For more information about LLQ and CBWFQ, see