Question

Suppose there is a 10Mbps link between a geostationary satellite and the base station on earth. If the propagation speed is 2.4 * 10^8 m/sec, the packet size is 20Mb, and the distance from the satellite to earth is 42,000 km, what is the propagation delay of the link? What is the transmission delay? Show your work.

Answer 1

Answer and Explanation:

Given,

`Distance=42000`

`Let\; Propagation\;Speed\;as\; PS=2.4* 10^8`

`Let\; Packet\;Length\;as\; PL=20\;MB`

We have to calculating the time needed for a packet to attain its location by the sender side. By applying the formula of propagation delay.

`\mathbf{Let\; Propagation\;Delay\;as\; PD=(Travelled\;Distance)/(PS)}`

`Then,`
`\mathbf{PD=(42000*10^3)/(2.4 * 10^8)}`

So, the PD that is Propagation Delay is 0.175 sec.

Finally, We have to measuring the time necessary to move all those other bits to physical media. By applying the formula of transmission delay.

`\mathbf{Let\; Transmission\;Delay\;as\; TD=(PL)/(Data\;Rate)}`

`Then,`
`TD=(20)/(10)`

So, the TD that is transmission Delay is 2 sec