Bandwidth vs Bandwidth Remaining

This topic is to discuss the following lesson:

Hi Rene, for BW remaining percentage config, if other classes such AF11, AF21 and AF31 are not in use, then can the Default class take the unused BW from these 3 classes OR will BW remaining percentage for AF11(8 Mbps) , AF21(16 Mbps) or AF31(24 Mbps) will always be reserved for them and cant be used by Default or any other class?

Hello Sandeep

Remember, that these values are referring to bandwidth guarantees that exist during congestion. In other words, this is reserved bandwidth for that particular type of traffic.

Now if there is no AF11, AF21, and AF31 traffic at a particular time, then all other configured traffic types (EF and class-default) will share the full bandwidth of the interface as needed. But such traffic will be served in a best-effort manner, no guaranteed bandwidth is provided beyond what has been configured.

So if you were to examine the results of such a situation in the lab, you would see that any additional bandwidth available would show up under the class-default.

But be aware that this is not guaranteed bandwidth that you are seeing, but best effort.

I hope this has been helpful!


Remember, when configuring these values (whether percentage or percentage remaining) they define the minimum guaranteed bandwidth

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