How does flowvisor slice bandwidth on exactly one link

[KerKerRed]

Hi all

I'm beginner of FlowVisor.

And I'm confused about how does FlowVisor slice bandwidth.

I know FlowVisor can set "rate-limit" to slices. And this will guarantee minimum bandwidth for this slice.

But in this web. http://archive.openflow.org/wk/index.php/Slicing

It create two queues in one port in a switch, one queue has 70% bandwidth and another has 30%

and there are two slices each connect to one queue.

I'm confused why can't I just set the rate limit of two slices ?

Does anyone have same experience of slicing bandwidth can give me some suggestion?

Thanks a lot !