  For high-speed quantum key distribution systems, error reconciliation is
often the bottleneck affecting system performance. By exchanging common
information through a public channel, the identical key can be generated on
both communicating sides. However, the necessity to eliminate disclosed bits
for security reasons lowers the final key rate. To improve this key rate, the
amount of disclosed bits should be minimized. In addition, decreasing the time
spent on error reconciliation also improves the key rate. In this paper we
introduce a practical method for expeditious error reconciliation implemented
in a Field Programmable Gate Array for a discrete variable quantum key
distribution system, and illustrate the superiority of this method to other
similar algorithms running on a PC. Experimental results demonstrate the
rapidity of the proposed protocol.
