Cryptography Stack Exchange
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Questions tagged [multiple-encryption]

Multiple encryption means encrypting a message two or more times using either the same, or a different algorithm.

Multiple encryption, cascade ciphering or superencryption refers to the process of encrypting the same data several times.

A well known result by Maurer and Massey (1993) shows that, under very general assumptions, a multiple encryption scheme is at least as secure as the innermost layer, provided that the encryption keys for each layer are independent. Furthermore, if the encryption layers commute (as is the case e.g. for additive stream ciphers), this shows that the combined encryption scheme is at least as secure as the strongest layer.

References:

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"Double Encryption" using the same cipher?

When it comes to the words "double encryption", I cringe. What I see is the following scenario play out. Someone has plain text and they encrypt it with the AES cipher using the 14 round variant, so AES256. Then they run that encrypted…
UnlistTed
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Encryption-Decryption-Encryption

I have learned from Applied Cryptography that triple encryption with three independent keys in encryption-decryption-encryption (EDE) process gives security not higher then $2^{2n}$ when it comes to meet-in-the-middle attack, where $n$ is keysize.…
Giliweed
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Database vs SAN vs Network Encryption

Good day everyone! Please bear with me as this is my first post on the crypto exchange. An interesting question was raised in a meeting recently about the double-encryption problem (i.e. same algorithm used on same message block twice yields weaker…
PrometheusRising
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References for cascade

I have found many sources against cascading encryption, however I am having trouble finding arguments FOR using cascading. AES-256 + BlowFish + RC5 etc... each with a different key. This is for university, so preferably need sources I can reference…
k1308517
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Combining cascaded encryption keys into one key

Is there an encryption algorithm where it's possible to combine multiple encryption keys into one, so that: $E_{AB}(Data) = E_A(E_B(Data))$ KeyAB should be computable from KeyA and KeyB, but it must not be possible to compute or guess KeyA or KeyB…
Jaka Jaksic
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Cascade Encryption with Faulty Inner Layer

First of all a couple of things: I am aware that cascade encryption tries to solve a problem that isn't present often. Attacks are more likely to be mounted against implementation details instead of creating a pure cryptoanalytic break on modern…
blaze5641
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