Question

Host A sends real time voice to Host B over a packet switched network. Host A first converts the analogue voice signal to a digital signal at a rate of 64 kbps. Host A then creates packets of data where each packet contains 56 bytes. Once a packet is created by Host A, it is sent to Host B over a link that operates at a 2 Mbps transmission rate. The propagation delay is 10 milliseconds. (Remember to convert bytes to bits). How many seconds does it take to create a packet of data?

Answer 1

Answer:

Time required is 0.007 s

Explanation:

As per the question:

Analog signal to digital bit stream conversion by Host A =64 kbps

Byte packets obtained by Host A = 56 bytes

Rate of transmission = 2 Mbps

Propagation delay = 10 ms = 0.01 s

Now,

Considering the packets' first bit, as its transmission is only after the generation of all the bits in the packet.

Time taken to generate and convert all the bits into digital signal is given by;

t = $\frac{Total\ No.\ of\ packets}{A/D\ bit\ stream\ conversion}$

t = $\frac{56\times 8}{64\times 10^{3}}$          (Since, 1 byte = 8 bits)

t = 7 ms = 0.007 s

Time Required for transmission of the packet, t':

$t' = \frac{Total\ No.\ of\ packets}{Transmission\ rate}$

$t' = \frac{56\times 8}{2\times 10^{6}} = 2.24\times 10^{- 4} s$