Figure 2: Cos Classifier, Queues, And Scheduler; Figure 3: Packet Flow Through Cos Configurable Components - Juniper EX9200 Series Overview Manual

Class of Service Overview and Examples for EX9200 Switches
16
The scheduler defines how traffic is treated in the output queue—for example, the
6.
transmit rate, buffer size, priority, and drop profile (at the
hierarchy level).
schedulers]
The scheduler map assigns a scheduler to each forwarding class (at the
7.
class-of-service scheduler-maps]
The drop-profile defines how aggressively to drop packets that are using a particular
8.
scheduler (at the [edit class-of-service drop-profiles]
The rewrite rule takes effect as the packet leaves a logical interface that has a rewrite
9.
rule configured (at the
[edit class-of-service rewrite-rules]
rule writes information to the packet (for example, EXP or DSCP bits) according to
the forwarding class and loss priority of the packet.
Figure 2 on page 16 and Figure 3 on page 16
features, illustrating the sequence in which they interact.

Figure 2: CoS Classifier, Queues, and Scheduler

Figure 3: Packet Flow Through CoS Configurable Components

Behavior
Aggregate
Classifier
Scheduler/Shaper/RED
Rewrite
Marker Adaptive Shaper/Virtual Channels
hierarchy level).
show the components of the Junos CoS
Multifield
Input Policer
Classifier
Forwarding Class
and Loss Priority
(all platforms)
(J Series only)
[edit class-of-service
[edit
hierarchy level).
hierarchy level). The rewrite
Forwarding
Policy
Options
Fabric Scheduler
Output Policer (M320 and
T Series only)
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