Juniper JUNOSE 11.1.X - QUALITY OF SERVICE CONFIGURATION GUIDE 3-21-2010, Руководство по настройке

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Figure 30: Implicit Constituent Selection for Compound Shared Shaper at Best-Effort Queue
Figure 30 on page 111 illustrates other examples of implicit constituent selection. It
does not reflect typical configurations, but includes a mixture of interface types: IP,
VC, and VP. If only scheduler profile A is applied, the associated interface is VC 1.
The selected constituents then consist of the VC 1 best-effort node, the VC 1 TC voice
queue, and the VC 1 TC video queue.
If only scheduler profile B is applied, the associated interface is IP 1. The selected
constituents then consist of the IP 1 best-effort queue, the IP 1 TC voice queue, and
the IP 1 TC video queue.
If only scheduler profile C is applied, the associated interface is VP 1. The selected
constituents then consist of the VP 1 default group node, the VP 1 Group EF node,
and the VP 1 Group AF node.
Implicit Bandwidth Allocation for Compound Shared Shaping
After selecting the implicit constituents for compound shared shaping, the router
places the constituents in an order that determines how the constituents can claim
a share of the available shared bandwidth.
When it implements compound implicit shared shapers, the software selects attributes
for the active constituents consistent with the hierarchical scheduler.
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Auto-strict nodes and queues have the highest priority.
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Nodes and queues in extended traffic-class groups are next.
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Nodes and queues in the default traffic-class group have the lowest priority.
For example, suppose a compound shared shaper has a rate of 2 Mbps. The shared
shaper has three active constituents: the best-effort node, a voice queue in the
auto-strict traffic-class group, and a video queue in an extended traffic-class group.
Implicit Constituent Selection Overview
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Chapter 13: Configuring Implicit and Explicit Constituent Selection for Shaping