Assume a packet is made only of four 16-bit words (A7A2)₁₆, (CABF)₁₆, (903A)₁₆, and (A123)₁₆. Manually simulate the algorithm in Figure 10.17 to find the checksum.

Figure 10.17

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Figure 10.17 Algorithm to calculate a traditional checksum Start Sum = 0 More words? Iyes] Sum = Sum + Next Word Ino] Left(sum) is nonzero? Įyes] Sum = Left(Sum) + Right(Sum) Notes: Ino] a. Word and Checksum are each Checksum = Complement (Sum) 16 bits, but Sum is 32 bits. b. Left(Sum) can be found by shifting Sum 16 bits to the right. c. Right(Sum) can be found by ANDing Sum with (0000FFFF. d. After Checksum is found, truncate Checksum = truncate (Checksum) 16 Stop it to 16 bits.