Noise: white, pink, brown, black, and buffers

Posted by on Nov 4, 2012 in Tutorial | 0 comments

Noise: white, pink, brown, black, and buffers

This post is a continuation of the previous one on network congestion. A white noise is one in which each sample is uncorrelated with any other. A white Gaussian noise is one in which the samples are distributed according to a normal curve with a stable mean and variance. The power spectrum of a white noise process is uniformly flat at all frequencies. One way to think about this property is to say that there is equal power in equal frequency bands. Another “brand” of noise is pink noise. The power spectrum of a pink noise falls off as 1/f and so this form of noise is often...

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Einstein, Hurst, and network congestion policy

Posted by on Sep 23, 2012 in Tutorial | 0 comments

Einstein, Hurst, and network congestion policy

We begin our story with good old Albert Einstein and his considerations of Brownian motion. In 1905, Einstein delivered four papers for publication that, in turn, addressed the photoelectric effect, Brownian motion, special relativity, and energy-mass equivalence. He could have been swept from the earth in 1906 and he’d still have been rightly famous for his work of 1905. Over 100 years later, folks are still struggling with the meaning of his work in that year. You can read what Albert had to say about Brownian motion for yourselves. Let’s turn to the bit on Brownian motion for...

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