Huawei S3700-28TP-PWR-SI 02354133 User Manual
Product codes
02354133
4.5.2 Access Control and Re-marking
After traffic classification, the S3700 performs access control on the packets, that is, permits or
denies the packets. Then, the S3700 re-marks the following fields in the packets:
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denies the packets. Then, the S3700 re-marks the following fields in the packets:
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802.1p field, that is, the PRI field in a VLAN tag
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DSCP field
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Precedence field of IP packets
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VLAN ID, that is, the outer VLAN ID or inner VLAN ID of QinQ packets
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Destination MAC addresses
4.5.3 Traffic Policing
The S3700 uses the token bucket algorithm to control the Committed Access Rate (CAR) of
network traffic.
network traffic.
The S3700 controls the rate of traffic by adjusting the rate of placing tokens. Each token equals
a forwarding rate of 64 kbit/s. The S3700 "punishes" the excessive traffic to limit the incoming
traffic within a proper range and to protect the network resources.
a forwarding rate of 64 kbit/s. The S3700 "punishes" the excessive traffic to limit the incoming
traffic within a proper range and to protect the network resources.
4.5.4 Congestion Management
The S3700 manages traffic congestion through queue scheduling. Each outbound interface on
the S3700 is configured with eight queues. After traffic classification, packets are sent to the
corresponding queues based on their priorities.
the S3700 is configured with eight queues. After traffic classification, packets are sent to the
corresponding queues based on their priorities.
The S3700 provides the following queue scheduling policies:
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Priority Queuing(PQ)
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Weight Round Robin(WRR)
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Deficit Round Robin(DRR)
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PQ + WRR
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PQ + DRR
4.5.5 Congestion Avoidance
Congestion avoidance is a flow control technology that relieves overload on a network by
adjusting the network traffic. By monitoring the network resources in use, such as queues and
memory buffers, the S3700 automatically discards packets when congestion occurs or tends to
aggravate.
adjusting the network traffic. By monitoring the network resources in use, such as queues and
memory buffers, the S3700 automatically discards packets when congestion occurs or tends to
aggravate.
The adopts the Simple Random Early Detection (SRED) technology to avoid congestion. After
traffic classification, the marks packets with two types of drop precedence. Packets with low
request for QoS are marked with high drop precedence, and the other packets are regarded as
normal packets. Based on the drop precedence of the packets, the can discard packets to adjust
the rate of the outbound traffic sent from its interfaces.
traffic classification, the marks packets with two types of drop precedence. Packets with low
request for QoS are marked with high drop precedence, and the other packets are regarded as
normal packets. Based on the drop precedence of the packets, the can discard packets to adjust
the rate of the outbound traffic sent from its interfaces.
S3700HI
The S3700HI supports the Weighted Random Early Detection (WRED) algorithm. WRED
monitors packets in each queue and compares the length of the queue with the low threshold for
dropping packets. Based on the result, the S3700HI processes the packets in queues in the
following ways when congestion occurs.
monitors packets in each queue and compares the length of the queue with the low threshold for
dropping packets. Based on the result, the S3700HI processes the packets in queues in the
following ways when congestion occurs.
S3700HI Ethernet Switches
Product Description
Product Description
4 Service Features
Issue 05 (2012-10-20)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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