# Foruzan, Error Detection and Correction :Exercise Ques: 32 Please Explain

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32: A sender needs to send the four data items Ox3456, OxABCC, Ox02BC, and OxEEEE. Answer the following:

a. Find the checksum at the sender site.

b. Find the checksum at the receiver site if there is no error.
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data items given in hexadecimal. So, convert it into binary and then add all these binary codes.if there is a carry then add it. finally do the 1's complement of the result after addition and it will be called 16-bit checksum at sender side. append it to the data items and send it to receiver. if at receiver after adding these codes,if answer is zero then there is no error and checksum will be same at receiver.

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