First the 30 megabits (I don't know what MPBS is) is from you to your ISP's "world" and not the speed you'll get to any server on the internet. Inside your ISP's world, you may see that 30 or close to it but no ISP will tell you will get 30 to outside their system.
Cnet just published/designed/sent out their version of a speedtest at http://www.cnet.com/internet-speed-test/#ftag=CAD-04-10aac3d.
I got 11 MPBS.
I pay for 30.
Ookla (speedtest.net) shows I typically get 28-31 MPBS.
Why is there such a difference?

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