Interactive end-of-chapter exercises


Longest Prefix Matching

Consider a datagram network using 8-bit host addresses.
Suppose a router uses longest-prefix matching, and has the following forwarding table:



Question List


1. Suppose a datagram arrives at the router, with destination address 10110111. To which interface will this datagram be forwarded using longest-prefix matching?

2. Suppose a datagram arrives at the router, with destination address 11011101. To which interface will this datagram be forwarded using longest-prefix matching?

3. Suppose a datagram arrives at the router, with destination address 00010101. To which interface will this datagram be forwarded using longest-prefix matching?




Solution


1. Since the address is 10110111, it will go to interface 3.

2. Since the address is 11011101, it will go to interface 5.

3. Since the address is 00010101, it will go to interface 6.



That's incorrect

That's correct

The answer was: 3

Question 1 of 3

The answer was: 5

Question 2 of 3

The answer was: 6

Question 3 of 3

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