Questions tagged [error-propagation]

Property of cryptographic primitives to propagate errors. This usually means that an "error" in one block propagates into the following blocks, thereby flipping bits there or completely scrambling those blocks. CBC has the first property (bit-error in one ciphertext induces bit-flip in the next plaintext-block) whereas PCBC is constructed to scramble all consecutives blocks on bit-error.

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Why does error propagation in CBC mode encryption affect two blocks?

From Wikipedia: Error propagation It was common to discuss the "error propagation" properties as a selection criterion for a mode of operation. It might be observed, for example, that a one-...
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Is error propagation desired in modes of operation

I'm taking a very simple class on cryptography. The class is not mathematical is just the very basics. We learned about modes of operations recently (such as CBC and CTR), one of the things I learned ...
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Error propagation in CBC mode

Going through the wiki for modes of operation I see that the section error propagation says that an error in one block in the ciphertext in CBC mode only impacts two blocks. I do not quite get that. ...
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Single bit error in CBC

Why does a single bit error when using the CBC block cipher mode of operation affect the decryption of a block (Oj) with a probabilty of 50%? And in the following block, why is the one bit error in ...
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Show number of affected blocks using CFB DES decryption of altered ciphertext

I have encrypted a file using -des -cfb and now I want to view how many blocks it contains once I decrypt it. I have done this on the Linux terminal. I know that 9 ...
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What is the use of segments in Cipher Feedback Mode (CFB)

In NIST SP800-38A: Recommendation for Block Cipher Modes of Operation CFB can be used with a parameter s - the size of a data segment in bits - which determines the ...
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Propagating CBC insecure Authenticated Encryption

why is Propagating CBC (PCBC) insecure for authenticated encryption? I received the hint that I should feed a message of length $n$ and a message of length $n-1$ to it, but I don't really get what the ...
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Error Detection/Correction technique for Encypted Data

I will be very pleased if anyone can clarify me that, can we use the same error detection/correction techniques like (Convolutional code) for the error detection/correction of encrypted data. Or do we ...
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How do quantum key distribution systems tolerate noise?

It seems to me that any noise in the signal would result in Alice and Bob generating different keys, without a simple way to tell the difference. How do quantum key distribution systems tolerate ...
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8-bit CFB in DES and AES - error propagation

I have two questions for an assignment that I need to answer in relation to Error Propagation in 8-bit CFB mode for AES and DES encryption. The questions are as follows: If there is an error in ...
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CRC32 catches errors, but then what's the point of SHA?

If crc or CRC32 is specially designed to catch errors, then what's the point of SHA or md4-5 or any other hashing function? What I did was, I had a 190 mb png file (rendered in 16k resolution with ...
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Error propagation in CBC

I am doing an error propagation experiment with the CBC mode.I have encrypted a 100 byte text file with openssl. I made the 55th bytes of my encrypted file corrupted.As per theory the corresponding ...