Quantum Error Correcting Codes and The Security of BB84 Part III - Richard Cannings

This is the final lecture of the security proof of BB84. In this lecture, we slightly alter the general entanglement purification protocol, and then prove that it is a secure quantum key distribution (QKD) protocol called the Modified Lo--Chau QKD. Finally, we reduce the Modified Lo--Chau QKD to BB84 by a series of simple reductions.