Difference between revisions of "Willi Meier"

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'''Title''' Near-colliding Keys in RC4
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'''Title''': Near-colliding Keys in RC4
  
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'''Abstract''': Search of key collisions in the RC4 stream cipher has been an active area. We investigate near-colliding keys that lead to related states after key scheduling and related key stream bytes.
 
 
'''Abstract '''
 
 
 
Search of key collisions in the RC4 stream cipher has been an active area. We investigate near-colliding keys that lead to related states after key scheduling and related key stream bytes.
 
 
Our investigation reveals that near-colliding states do not necessarily lead to near-colliding key streams.
 
Our investigation reveals that near-colliding states do not necessarily lead to near-colliding key streams.
 
From this motivation, we present practical methods to find a related key pair with differences in two bytes,
 
From this motivation, we present practical methods to find a related key pair with differences in two bytes,
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(the last two bytes increased and decreased by 1 respectively), the first pair of bytes corresponding to the
 
(the last two bytes increased and decreased by 1 respectively), the first pair of bytes corresponding to the
 
related keys are the same with significant probability (e.g., approximately 0.011 for 16-byte keys to 0.044 for 30-byte keys).
 
related keys are the same with significant probability (e.g., approximately 0.011 for 16-byte keys to 0.044 for 30-byte keys).
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'''Slides''': [[Nearcollisionrc4.pdf ]]

Revision as of 10:33, 18 January 2013

Title: Near-colliding Keys in RC4

Abstract: Search of key collisions in the RC4 stream cipher has been an active area. We investigate near-colliding keys that lead to related states after key scheduling and related key stream bytes. Our investigation reveals that near-colliding states do not necessarily lead to near-colliding key streams. From this motivation, we present practical methods to find a related key pair with differences in two bytes, that leads to a large number of matches in the initial key stream. In the process, we discover a class of related key distinguishers for RC4. The best one of these shows that given a random key and a related one to that (the last two bytes increased and decreased by 1 respectively), the first pair of bytes corresponding to the related keys are the same with significant probability (e.g., approximately 0.011 for 16-byte keys to 0.044 for 30-byte keys).

Slides: Nearcollisionrc4.pdf