Leftover hashing from quantum error correction: Unifying the two approaches to the security proof of quantum key distribution

Understand

We show that the Mayers-Shor-Preskill approach and Renner's approach to proving the security of quantum key distribution (QKD) are essentially the same.

• We begin our analysis by considering a special case of QKD called privacy amplification (PA).
• PA itself is an important building block of cryptography, both classical and quantum.
• The standard theoretical tool used for its security proof is called the leftover hashing lemma (LHL).