Networking Projects CCNA Interview questions - July 2013 | Page 5

Question 2
In the above diagram , the computer with IP address 192.168.1.2 pings the router with IP address 192.168.1.1 . Explain how the packet is processed by the router and whether routing is involved in the scenario .
Explanation
The computer constructs the IP header with source IP address as 192.168.1.2 and destination IP address as 192.168.1.3 . The IP header would be encapsulated in an ethernet frame with source mac-address as that of the computer ’ s mac-address and destination mac-address as the router ’ s mac-address . When the frame reaches the router , the router looks into the destination mac-address of the frame . On a match , the FCS value of the frame is calculated and verified . The router then looks into the destination IP address of the IP header . Since the IP address is intended for itself , the router prepares a response . There is no routing involved since the destination IP address is on the same physical segment .
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