Quantum Key-length Extension

@article{Jaeger2021QuantumKE,
  title={Quantum Key-length Extension},
  author={Joseph Jaeger and Fang Song and Stefano Tessaro},
  journal={ArXiv},
  year={2021},
  volume={abs/2105.01242}
}
. Should quantum computers become available, they will reduce the effective key length of basic secret-key primitives, such as blockciphers. To address this we will either need to use blockciphers with inherently longer keys or develop key-length extension techniques to amplify the security of a blockcipher to use longer keys. We consider the latter approach and revisit the FX and double encryption constructions. Classically, FX was proven to be a secure key-length extension technique, while… 

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