DiffServ for VoIP Configuration Example
161
22 Differentiated Services
DiffServ for VoIP Configuration Example
One of the most valuable uses of DiffServ is to support Voice over IP (VoIP). VoIP traffic is
inherently time-sensitive: for a network to provide acceptable service, a guaranteed
transmission rate is vital. This example shows one way to provide the necessary quality of
service: how to set up a class for UDP traffic, have that traffic marked on the inbound side, and
then expedite the traffic on the outbound side. The configuration script is for Router 1 in the
accompanying diagram: a similar script should be applied to Router 2.
Figure 106.
DiffServ VoIP Example Network Diagram
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*
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#
Port 0/2
Port 0/3
Layer 3 Switch
operating as
Router 1
Layer 3 Switch
operating as
Router 2
Internet
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