A stream cipher is an encryption algorithm which encrypts arbitrary length plain text, using a (fixed length) key. Some stream ciphers generate a key stream from only the key, which is then XOR-combined with the plain text, others feed back plain text or cryptotext into the algorithm to create the ...

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I don't know whattype of cipher this is [on hold]

I am trying to solve the following sipher Nosdhiibotidcylhrdeovedljuetre I have no experience with ciphers but substitution didn't seem to work, and since its a long string without breaks process of ...
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32 views

What is the general idea of truncated differential attack on hash functions?

What is the general idea of truncated differential attack on hash functions ? i'm using stream cipher and sponge hash construction and i want to know what is the general idea of differential attack ...
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42 views

Decypting a Stream Cipher

I am trying to decrypt a stream cipher. I know what the first word of the message is when decrypted but I am unsure how to decrpyt the rest of the message. I know what the first word is because I ...
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40 views

Resynchronizing brute-force attack against stream ciphers

There is a stream cipher without any known cryptographic weaknesses. The attacker knows parts of the key so she can reduce the key-space to a size that can be practically brute-forced. However the ...
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2answers
135 views

Reusing a one-time pad?

I have an embedded device. It produces larges files (200 MB). I want the device to encrypt the file before writing to disk, so I gave them all a 16-byte random key. How can I transform the large ...
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58 views

symmetric encryption A5/1 and A5/2 algorithms

where does the key (Kc) used to generate the keystream comes from and also where does the 22bits counter comes from
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3answers
907 views

Block Cipher vs Stream Cipher in Web Application [closed]

I'm doing research about "Cryptographic attack methods in Web Application" so I have some questions to ask you guys: Block Cipher vs Stream Cipher, which is more common used in Web Application? How ...
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1answer
290 views

Why RC4 used constant 24bits for initial vector

Why RC4 used 24-bits constant value + 40 bits random values to generate key?
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1answer
141 views

What's the best packet cipher mode for use with UDP for example? Advantages or disadvantages of any alternatives?

Cipher modes typically assume data is streamed or read from a reliable channel with guaranteed ordering. However, many communication transports, such as UDP, are not reliable and don't guarantee order ...
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28 views

what is the best Encryption algorithm to encrypt real time voice [closed]

i am developing real time secure voice transmission application and i am not sure what is the best encryption algorithm to encrypt voice
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387 views

Why is there a strong distinction between stream and block ciphers? [duplicate]

If I don't err, in the literature a stream cipher is one in which each plaintext bit is processed individually, commonly via xor-ing with one bit of a random or pseudo-random bit stream, while a block ...
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1answer
69 views

XOR = Best encryption? [duplicate]

If you have a TRULY random key (in binary) and you have a text (in binary) that you want to encrypt. Can you simple XOR the key and the text? Is that secure? How secure?
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What is the best (thoroughly covering) textbook for application of LFSRs in cryptography? [closed]

What is the best (thoroughly covering) textbook for application of LFSRs in cryptography? (Beside Cipher Systems by Beker & Piper)