Question

1.       Suppose there are two routers between a source host and a destination host. Ignore fragmentation; an IP datagram sent from the source host to the destination host will travel over how many interfaces? How many forwarding tables are there to move the datagram from the source to the destination?

1.       Consider a datagram network using 32-bit host addresses. Suppose a router has three links, numbered 0 through 2, and packets are to be forwarded to the link interfaces as follows:

Prefix                                    Link Interface

11100000 00                                        0

11100000 01000000                          1

Other                                                    2

Determine output interface for each of the following three destination addressed:

11001000 10010001 01010001 01010101

11100000 00101010 00000000 10101010

11100000 01000000 10000001 01000010

1.       With subnet as 123.45.76.0/24, how many address are there in this subnet?

Which of the following address belong to this subnet? 123.45.76.77, 123.45.77.76, 123.45.76.255, 124.45.76.1

Answer 1

1. The datagram will go through the total of the 6 interfaces and the total of 2 forwarding tables. their will be 6 interfaces as the SOURCE, R1L , R1R ,R2L , R2R , DESTINATION , so these are the interfaces from the which the datagram will be needed to pass through to reach the destination and the as their are two routers in the network so , our datagram will be subjected to one forwarding table from each router , so the datagram need to go through 2 forwarding table.