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What's 2*80 in Hexa? (AES key expansion Round Key confusion)

shivajikobardanshivajikobardan Member Posts: 20 ■■□□□□□□□□
in CISSP



The result is shown to be 1B. How did we get this value?


So, this looks like a case of carry in hexa addition, so how'd we do this calculation?


I'm asking this question because of this. Here' for j=8, Round Constant is 80. The formula to find next round constant is to multiply the current round constant with 2. So, it's 2*80 and should be 100. But it's not the case. So, I want to know how is it done?


Source: https://uomustansiriyah.edu.iq/media/lectures/5/5_2021_06_05!07_10_53_PM.pdf


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