3com S7906E Installationsanweisungen
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Figure 12-1 QoS model for uplink traffic in an EPON system
QoS Functions for Downlink Traffic
Processing on an OLT
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Configuring the OLT to perform priority mapping for packets received from the uplink port
according to the CoS-to-local precedence mapping table and then assign packets to output
queues of the OLT port.
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Configuring the OLT to perform congestion management for downlink traffic, supporting SP and
WRR queue scheduling algorithms.
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Configuring the OLT to perform line rate and traffic shaping for downlink traffic.
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Configuring the maximum downlink bandwidth that the OLT assigns to the ONU.
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Configuring high-priority packet buffer for downlink traffic that the OLT sends to the specified ONU.
Processing on an ONU
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Filtering the packets matching certain match criteria according to the configured QoS policy.
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Configuring the ONU to distribute the received downlink traffic to different output queues based on
the mapping between the CoS precedence and local precedence.
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Configuring the ONU to perform traffic policing for downlink traffic of a UNI.
Some ONUs support configuring queue scheduling for traffic from a UNI. To perform such
configurations, you should log in to the ONU. For detailed configuration, refer to the ONU user manual.
shows the QoS model for downlink traffic in an EPON system.
Figure 12-2 QoS model for downlink traffic in an EPON system