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 01010100. To which interface will this datagram be forwarded using longest-prefix matching?

2. Suppose a datagram arrives at the router, with destination address 11000010. To which interface will this datagram be forwarded using longest-prefix matching?

3. Suppose a datagram arrives at the router, with destination address 11111000. To which interface will this datagram be forwarded using longest-prefix matching?




Solution


1. Since the address is 01010100, it will go to interface 2.

2. Since the address is 11000010, it will go to interface 6.

3. Since the address is 11111000, it will go to interface 6.



That's incorrect

That's correct

The answer was: 2

Question 1 of 3

The answer was: 6

Question 2 of 3

The answer was: 6

Question 3 of 3

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