Question

How long does it take a packet of length 1,000 bytes to propagate over a link of distance 2,500 km, propagation speed 2.5 · 108 m/s, and transmission rate 2 Mbps?

Answer 1

10 ms

Step-by-step explanation:

Length of packet = 1000 bytes

Distance of link = 2500 km

Propagation Speed = 2.5 x 10^8 m/s

Transmission Rate = 2 Mpbs

To find: Time a packet takes to propagate over a link

Propagation Time = ?

Solution:

Propagation Time = Distance of Link/Propagation Speed

tprop = d/s=

Distance is in kilometers. First convert it into meters.

2500*1000 = 2500000 meters

Distance of link = 2500000 m

Propagation Speed = 2.5 x 10^8 = 2.5 x 100000000 = 250000000

Propagation Time = (2500*)/(2.5*10^8)

= 2500000/250000000

=0.01 sec

Convert 0.01 second into millisecond:

0.01 x 1000 = 10 ms

So

Propagation Time = 10 ms