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EF_BE Model

There is a simple model which can be used to configure just the Premium EF flow and BE. The architecture has an outer ds_mark queue 1:0 attached to the device, then we have a 2:0 CBQ derived from this ds_mark queue, this inturn has two classes 2:1 and 2:2 for EF and BE traffic. The 0xfc filter extracts the codepoint from the TOS byte in the packets and stores them in the skb->tc_index. Then we have the 0x2e filter for directing EF packets into class 2:1 and the handle 0 filter for BE traffic into class 2:2. The EF class is associated with a pfifo queue and the BE class has a RED queue attached to it. 
Figure 3: EF BE Architecture

 The bandwidths for the EF and BE traffic can be configured by the user. Sample result with this configuration. 

Flow Type	Bandwidth (Mbps)	Throughput at Tx (Mbps)	Throughput at Rx (Mbps)
EF traffic	7	6	5.9441
BE traffic	0.5	0.5	0.352

1999-12-19