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Chapter 5 QoS in a SOHO Virtual Private Network for IP Telephony
QoS Toolset
Figure 5-1
Areas of a SOHO Network Where QoS is Needed
QoS Toolset
The challenges of packet loss, delay, and delay variation can be address through the application of
various QoS tools.
This section provides information about the use of QoS tools in a SOHO environment. For general
information about the QoS Toolset, see the
Classification
Within a SOHO AVVID network, you should classify voice bearer and signaling traffic.
For general recommendations for classification, see
Classification of Voice Bearer traffic
In a SOHO AVVID network, you must classify packets that contain voice traffic so that they can be
placed into the appropriate queues. The recommended DSCP PHB label of Expedite Forward (EF) for
should be used for VoIP traffic. To remain backwardly compatible with IP Precedence, use an IP
Precedence value of 5 and a CoS marking of 5.
These markings can be used as selection criteria for entry into the priority queue, where it exists, or the
queue with the highest service weight and lowest drop probability in a WRR/WRED scheduling scheme.
IP
IP
IP
Areas where QoS
may be a concern
Two-box
Third-party modem
Single-box
3rd-party
modem
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Backbone
To head
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