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network-programmingpropagationtransmission

Transmission and propagation delay

I have a very simple calculation for the delay over a simple link and i do not understand a part in the solution.

Consider that:

I have a 10Mbps line, 200.000.000 m/s cable speed, 2.000 km distance, and 8.000 bytes file.

The solution is this: enter image description here

I do not understand why an extra '8' is added in 'L' and an extra '10' is added in 'C'. Can someone please explain it to me?

I searched it on Google and i could not find an answer, although i assume that this is something basic (maybe i don't know how to search properly :p)

Thanks in advance.

Solution

  • Simple maths i guess

    • 1 Byte = 8 bits ; so you have 8
    • 8 * 1000 = 8000 ; you have another 8
    • 10 Mbps = Ten Mega bits per second
    • Mega = 1,000,000 ; you have 10 in front

    So in conclusion

    • 8.8.10^3 == 8000 bytes
    • 10.10^6 == 10Mbps

    Hope I helped you with MATH ;)