Achieving Perfect Secrecy

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Achieving Perfect Secrecy

• Jorge Carrillo Ugalde
• xugalde_at_fi.muni.cz

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Symmetric cryptosystem.
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Security Assumptions.
Unconditional Security.
Computational Security.

• If the best known method of breaking the
  cryptosystem requires an unreasonably large
  amount of computer time.

• If the cryptosystem can not be broken, even with
  infinite computational resources.

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Sharing a random number.
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Sharing a random number.
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New cryptosystem Definitions.
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New cryptosystem Encryption.
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New Cryptosystem Decryption.
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New Cryptosystem Visual representation.
gk
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Approximation
Message
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New One Time Pad Definitions.
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New One Time Pad Making a partition.
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New One time Pad Encryption/Decryption.
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New One Time Pad. Final step.
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K O N E C