Figure 9 Relationships Between Wred And Queue Mechanism - Zte ZXR10 5900 Product Description

ZXR10 5900 5200 Product Description
low-pass. It can both indicate the changing trend of the queue, and be insensitive to
burst changes of queue length, and avoid unfair treatment to those data flows.
WRED is aware of in-band QoS identifications such as IP priority and DSCP, and can set
the packets of different IP priorities or DSCP with different queue length filtering
parameters, queue thresholds, and drop probability etc., thus it offers different dropping
characteristics for packets with different priorities.
The relationship between WRED and queue mechanism is shown in Figure 9:
Figure 9 Relationships between WRED and Queue Mechanism
With WRED and WFQ used together, flow-based WRED can be implemented. The
reason is that different flows have their own queues when being classified, and smaller
flows tend to have shorter queue length, which reduces their probability of being
dropped. While larger flows tend to have longer queue length and may be dropped more,
which protects the interests of those smaller flows.
3.19.2.4 Traffic policing
Traffic policing is typically used to restrict traffic and bursts which enter certain
connection of a network. The ZXR10 59/52 switch series support traffic policing
algorithm in RFC-defined single-rate and dual-rate color-blind/color-sensitive mode.
When packets meet conditions such as excessive packet traffic for a connection, traffic
policing will process them in different ways such as dropping packets or resetting their
priority, etc. A common practice is using Committed Information Rate (CIR) to restrict the
traffic for certain type of packets, such as confining the HTTP packets to within 50% of
the network bandwidth.
For ISPs, it is critical to control the traffic sent into the network by the users. For
enterprise networks, restricting the traffic of some applications prove to be an effective
tool to control network state, since network administrators can use the CIR to control the
traffic.
CIR controls traffic using Token Buckets (TB):
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