QOS with threshold and buffer on switch

[Horacio Gutierrez]

Hello, I know there 4 queue and with 3 threshold each one. My question what is the difference between the buffer and threshold percentage. For example if the buffer for traffic is 90% then how does the threshold apply to the buffer. Can I get example off percentage with buffer and threshold? Thanks,

[mtarawne]

Hello,

Buffer means the memory allocated for that queue 

Threshold means at which level will starting dropping the traffic due to congestion

let me give you an example :

lets say queue number 1 has 25% buffer allocated and this equals 25 mb

if we set threshold to 25% this means that we will start dropping traffic after reaching 25% of 25mb which is 6.25 mb

let me know if you got it or not 

regards,

[Joseph W. Doherty]

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For what (exactly) hardware?

In general, buffers provides the physical capacity of how many frame/packets might be queued.  Thresholds provide logical frame/packet limits.  How the two interact can vary based on hardware.