1 .Checksum for sender data?

2. Actual Checksum?

3. If checksum of sender is correct, what value is accepted at receiver?

4. If checksum of sender is incorrect, what is the value of checksum?

Internet Checksum Algorithm Sender Receiver 12 12 6 Initialized checksum-> 0 Received Checksum 9 Sum (in one's complement)- Sum (in one's complement)-+ 15 Calculated Checksum 0 6 7, 11, 12, 0, 6, 9 Actual checksum Packet Sender Receiver 1. The message is divided into 16-bit words.1. The message and the checksum is received. 2. The value of the checksum word is 2. The message is divided into 16-bit words. initially set to zero 3. All words including the checksum are 3. All words are added using one's comple- added using one's complement addition. ment addition 4. The sum is complemented and becomes 4. The sum is complemented and becomes the checksum. the new checksumm 5. The checksum is sent with the data 5. If the value of the checksum is 0, the message is accepted; otherwise, it is