Question

4 UDP Checksum (20 pts) Suppose a sender that is to send a UDP datagram as given below. It is creating the checksum 0000 110 0000 0110 0000 1000 Checksum 1. Find the binary sum of the other four fields than checksum. (4 pts) 2. Wrap around the overflow and add to the least significant bit(s) if any. (4 pts) 3. Find the l's complement of the result of Problem 2. (2 pts) Suppose a receiver. Your answer of Problem 3 has been sent in the check sum field 0000 1101 0000 0110 0000 1000 Your answer of Problem 3 . Perform the UDP checksum. 10 pts) Hint l. Sum the five fields. Carry the overflow into the least significant bit 3. Take 1's complement See whether fhe result is 0

Answer 1

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