While we're here, Christof Paar's 'Introduction to Cryptography' lecture series (freely available on YouTube here in English: [link] , originally delivered at Ruhr University Bochum) is a really excellent explanation of the internals of a number of crytographic algorithms. The lecture on Galois Fields ( ▶ this video ) is especially useful in understanding AES, and explains where some of the operations described in the blog linked here actually come from (i.e: S-Boxes used in AES are derived from inversion in finite fields).
in “Understanding how AES encryption works” · View on HN