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As per the Stallings book, the normal decryption of AES has different sequence of transformations [method 1 below], which leads to two separate software or firmware modules and that is undesirable.

However, with the interchange of the ISR and IBS operations during decryption (as they are equivalent), the encryption and the decryption can be given the same form. However, this second method needs a change in the key schedule. I can't find what this new key schedule is.

Encryption (method 1) : ARK BS, SR, MC, ARK, ….. BS, SR, MC, ARK, BS, SR, ARK
Decryption (method 1): ARK, ISR, IBS ARK, IMC, ISR, IBS ….. ARK, IMC, ISR, IBS ARK

Encryption (method 2): ARK BS, SR, MC, ARK, ….. BS, SR, MC, ARK, BS, SR, ARK
Decryption (method 2): ARK, IBS, ISR, ARK, IMC ….. IBS, ISR, ARK, IMC IBS, ISR, ARK

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