Security of distributed-phase-reference quantum key distribution
  Distributed-phase-reference quantum key distribution stands out for its easy implementation with present day technology. Since many years, a full security proof of these schemes in a realistic setting has been elusive. For the first time, we solve this long standing problem and present a generic method to prove the security of such protocols against general attacks. To illustrate our result we provide lower bounds on the key generation rate of a variant of the coherent-one-way quantum key distribution protocol. In contrast to standard predictions, it appears to scale quadratically with the system transmittance. 
Tobias Moroder, Marcos Curty, Charles Ci Wen Lim, Le Phuc Thinh, Hugo   Zbinden, Nicolas Gisin
quant-ph