RC4 is a fast and simple stream cipher used correctly in SSL and incorrectly in WEP.

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Explain the 'Breaking 104 bit WEP in less than 60 seconds' paper

Could you explain the 'Breaking 104 bit WEP in less than 60 seconds' paper, without skipping too much technical details. Could you an answer questions, like: how is '1.24/256' a significant ...
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How was 256-bit WEP cracked as well?

WEP is now considered as insecure. But how about the 256-bit WEP? Could someone explain why a 256-bit encryption isn't enough? 'A 256-bit WEP system is available from some vendors. As with the other ...
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How insecure in practice?

I am in attempt to understand relative insecurity of certain encryption schemes. Particularly of interest is DES and RC2. I know AES is better and should be used to encrypt. But practically, if ...
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Simple RC4 key generation scheme

I would like to ask you about your opinion on the following scheme of combining a master key and a nonce and stretching the result to the full 256-bytes RC4 key. Master key $K_m$ is a pre-shared ...
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Because the algorithm is known, it is no longer a trade secret [closed]

In wiki about RC4 cipher they said, Because the algorithm is known, it is no longer a trade secret. Is that mean the cipher text will be more secure if the algorithm unknown to the attacker. ...
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381 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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Is there a way to make RC4 (ARCFOUR) secure, or is it completely broken?

I need a method to authenticate a process with another in order to establish interprocess communication between them, to prevent malicious processes from trying to hook onto the system. Currently I ...
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1answer
451 views

Does TLS use RC4-drop[n]?

According to many sources, the first few (n) bytes of the RC4 keystream are strongly biased, and therefore should be discarded before using the keystream to encrypt anything; this precaution is ...
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RC4 S-Box and Keystream

I'm studying the RC4 algorithm and I have the following questions: On all questions assume that an expanded (2048-bit) key is used, and that the first 4096 bytes of the KeystreamIm are discarded. ...
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RC4 Keylength Limits

While reading the Wiki page on RC4 I noticed that the key size must be in the range of 40–2,048 bits. Why is that? Is there a reason it can't have a lower or higher length?
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Do these 2 KSA shortcuts weaken RC4?

Alice securely gives Bob a secret key so they can exchange 10 different messages encrypted with RC4. (Messages will include a counter for uniqueness and a MAC for authentication.) For each message ...
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826 views

What is the time complexity of the RC4 encryption & decryption algorithms?

I'm trying to figure out what the time complexity of RC4 encryption & decryption algorithms is, in big-O-notation.
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357 views

Has there been any cryptanalysis of RC4-52?

Several websites ( such as Is there a secure cryptosystem that can be performed mentally? ) briefly mention RC4-52 as a modification of standard RC4. RC4-52 has only with 52 instead of 256 elements ...
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How does one measure the decrease in security, if any, of RC4 when mapping to a specific range of values?

For a project using RC4, the output is to be mapped to values of 0 to 35. Thus, only 36 unique output values representing the letters A to Z and 0 to 9. To avoid bias, the RC4 byte output (with a ...
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2answers
215 views

How are constructs with data-dependent swaps and rotations cryptanalyzed?

Linear and differential cryptanalysis seem well suited for constructs with a (relatively) simple fixed structure of boolean expressions. But some ciphers incorporate swaps of array elements where the ...