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The time of sending a file is calculated: $$\textrm{time} = \frac{\textrm{file size}}{\textrm{link capacity}}.$$ In this example, $\textrm{file size} = 4492643566$ bytes, and $\textrm{link capacity} = 100$ Mbits/s. Sending the file and the header over $100$ Mbit/s link will take $359.4$ seconds $= 6$ minutes.

I don't understand the result, $4492643566/100 = 359$?

TMM
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user567
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    Note that $100\textrm{ Mbits} = 100,000,000\textrm{ bits} = \frac{100,000,000}{8}\textrm{ bytes}$. (This gives the correct result, although sometimes $1\textrm{ M}=2^{20}$ is used, see e.g. Wikipedia.) – JiK Feb 16 '14 at 14:24

1 Answers1

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Note the difference in units: 1 byte = 8 bits.

So multiply L by 8.

Link capacity is given in Mbits, 100 of them, and each Mbit is $1000000 = 10^6$ bits.

So you need to calculate: $$\dfrac{4492643566 \times 8\,\text{ bits}}{100\times 10^6 \text{ bits per second}}\approx 359.4\text{ seconds}$$

amWhy
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