Simulation of quantum key distribution with noisy channels

In this paper secure schemes for cryptographic key distribution - called quantum key distribution protocols - are investigated by means of computer simulation. For this, a general purpose quantum circuit designer and simulator program was developed and used. To be more realistic the protocols were ran on different noisy quantum channels. The aim is to determine the grade of security of the protocols in function of the channel parameters they are using; and also to propose a method for selecting the best protocol for a given channel.