ZyXEL Communications GS2200 Series, User Manual

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Chapter 31 Differentiated Services
GS2200 Series User’s Guide
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The DSCP value determines the PHB (Per-Hop Behavior), that each packet gets as it is forwarded
across the DiffServ network. Based on the marking rule different kinds of traffic can be marked for
different priorities of forwarding. Resources can then be allocated according to the DSCP values and
the configured policies.
DiffServ Network Example
The following figure depicts a DiffServ network consisting of a group of directly connected DiffServ-
compliant network devices. The boundary node (A in
Figure 154 ) in a DiffServ network classifies
(marks with a DSCP value) the incoming packets into different traffic flows (Platinum, Gold,
Silver, Bronze) based on the configured marking rules. A network administrator can then apply
various traffic policies to the traffic flows. An example traffic policy, is to give higher drop
precedence to one traffic flow over others. In our example, packets in the Bronze traffic flow are
more likely to be dropped when congestion occurs than the packets in the Platinum traffic flow as
they move across the DiffServ network.
Figure 154
DiffServ Network
31.2 Activating DiffServ
Activate DiffServ to apply marking rules or IEEE 802.1p priority mapping on the Switch.
Click IP Application > DiffServ in the navigation panel to display the screen as shown.
Figure 155
IP Application > DiffServ
G S B P
S
B
B
G P P S
P - Platinum
G - Gold
S - Silver
B - Bronze
G P P S
A