Let source X and destination Y be connected through four intermed
Let source X and destination Y be connected through four intermediate routers labeled R1, R2, R3 and R4. Determine how many times each packet has to visit the network layer and the data link layer during a transmission from X to Y.
A. <p>Network layer – 10 times and Data link layer – 10 times</p>
B. Network layer – 10 times and Data link layer – 6 times
C. Network layer – 6 times and Data link layer – 10 times
D. Network layer – 6 times and Data link layer – 6 times
Please scroll down to see the correct answer and solution guide.
Right Answer is: C
SOLUTION
|
Source or Destination (X or Y) |
|
Application layer |
|
Transport layer |
|
Network layer |
|
Data link layer |
|
Physical layer |
Router is a network layer device
|
R1, R2, R3 or R4 |
|
Network layer |
|
Data link layer |
|
Physical layer |
From source packet is sent: 1 Network layer, 1 Data link layer
At every router, packet is received and send: 1 Network layer and 2 Data link layers
There are 4 router and hence: 4 Network layer and 8 Data link layers
To destination packet is received: 1 Network layer, 1 Data link layers
network layer: 1 + 4 + 1 = 6
data link layer: 1 + 8 + 1 = 10