Postscript to  a two part series on Comcast throttling upstream bandwidth [1, 2]: a quick email exchange and Google search suggests that other subscribers noticed similar problems. Trevin,  a former colleague at MSFT wrote in a private communication that when using a remote backup service in the cloud, bandwidth is also capped around ~350kbps. Aside from an isolated thread on Slingbox community forums, this does not appear to have been publicized widely.

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