Networking Projects CCNA Interview questions - July 2013 | Page 7

In the above diagram , PC1 pings PC2 and a response is received by PC1 . Explain the end to end communication .
Explanation
When PC1 pings PC2 , the destination IP address is 192.168.2.2 . The routing table on PC1 understands that 192.168.2.2 is on a different network . Due to this , the packet needs to be sent to the gateway . The corresponding gateway for PC1 is 192.168.1.1 and is configured on the TCP / IP adapter . An ARP request is sent out on the network to discover the mac-address of 192.168.1.1 . Once the mac-address is received , an ethernet frame is created with the source mac-address as PC1 and destination mac-address as that of the router ’ s interface configured with the IP address 192.168.1.1 . The frame encapsulates the IP header with source IP address as 192.168.1.2 and destination IP address as 192.168.2.2 . When the frame reaches the router , the router would look into the destination mac-address inside the frame . On a match , the FCS value of the frame is verified and then the frame stripped . The router then looks into the destination IP address in the IP header . It then verifies if the destination network is known to it . Since the destination network , which is 192.168.2.0 , is a directly connected network on the other interface , a frame with the source mac-address as the 192.168.2.1 interface and destination mac-address as PC2 mac-address is created . The IP packet header is then encapsulated in the frame and sent out to the destination . For the response , the same procedure is followed . The difference would be the source IP address in the IP header would be 192.168.2.2 and the destination IP address is 192.168.1.2 .
Question 5 Give two reasons as to why Rip v2 should be used instead of Rip v1 . Explanation
Rip v1 is broadcast in nature . So the performance of the network would be affected . Rip v2 is multicast . So , only devices / routers which support Rip v2 would participate in the communication . Rip v2 also supports password for authentication , which Rip v1 does not have .
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