CX600 Version: V6R1C00SPC800;
how to present the WRED funciton in CX600 to customer
first of all,the WRED(Weighted Random Early Detection) is advance congestion avoidance technology. it use to avoid the TCP global synchronization through the random drop packets. it work inside one queue and base on the color to endue different drop priority.
the test manual as below:
generat the traffic with fixed speed limit on one queque cause the traffic congestion,then observe the red, yellow and green packets discarded performance meets our expectations of the effect of configuration.
the result refer to the attachement.
regarding the figures in attachement,the vertical axis the proportion of discarded, the horizontal axis represents the queue length; red, yellow, green, with three horizontal lines in figures.
the result analysis:
When the packet reaches the queue length <low-limit (low threshold), do not discard .
When the low-limit (low threshold) <packet queue length reaches <High-limit (high threshold), started randomly dropping packets.
When the packet reaches the queue length = High-limit (high threshold), discarding the discard percentage ratio = Configuration.
When the packet reaches the queue length> High-limit (high threshold), all of discarding (100% discard) .
noted: currently,WRED test can only suggest to be qualitative observation, not suggest to make quantitative analysis.