Context: I send data at a rate of 10Mbit/s on a link whose propagation speed is 2x10^8 m/s. I want to know
the <b>width</b> of each bit on the wire.
First, what units should the answer have?
~+ meters (or better meters/bit)
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Context: I send data at a rate of 10Mbit/s on a link whose propagation speed is 2x10^8 m/s. I want to know
the <b>width</b> of each bit on the wire.
What is the formula for the answer?
~+ w = s/R (which has the required units meters/bit
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Context: I send data at a rate of 10Mbit/s on a link whose propagation speed is 2x10^8 m/s. I want to know
the <b>width</b> of each bit on the wire.
What is the numerical answer (with units)
~+ (2 x 10^8 m/s)/(10 x 10^6 bit/s) = 2/10 * 10^2 m/bit = 20 m/bit
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If the link is d = 100km long, how many bits are simultaneously "in flight"?
~+ 100 x 10^3 m / (20 m/bit) = 5 * 10^3 bits = 5 kbits

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