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SIMON-128/128

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SIMON-128/128

NSA hardware-optimised lightweight block cipher (IACR 2013/404). Sibling of SPECK — SIMON targets gate-minimal hardware via bitwise AND while SPECK targets software via ARX. 128-bit block, 128-bit key, 68-round Feistel. Round function: f(x)=(x<<<1 & x<<<8)⊕x<<<2.

Securesymmetric

Plaintext / Input Message

Cryptographic Key / Shift

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XOR Cipher

Deprecated

A simple stream cipher performing byte-wise XOR operations between plaintext and key.

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One-Time Pad (OTP)

Secure

An unbreakable cipher when used with a truly random, single-use key of equal length to the plaintext.

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DES

Broken

Data Encryption Standard. A legacy 64-bit block cipher utilizing a 56-bit key size.

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Related Resources

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