Abstract: The Advanced Encryption Standard (AES) cipher can be performed in a manner that preserves the secrecy of cryptographic keys, even under the intense scrutiny of a reverse-engineer observing every aspect of the computation. A method can include loading a key in a non-standard representation. The method can also include processing the key with respect to data in at least three first type rounds and a plurality of second type rounds. The processing the key with respect to data can include either encrypting the data using the key or decrypting the data using the key. The first type rounds can be configured to maintain an order of channels of bits at an output from the order of corresponding channels of bits at an input. The second type rounds can be configured to vary the order of channels of bits at an output from the order of corresponding channels of bits at an input.