Abstract

When using secret key cryptography, key transport is the main difficulty. Bennett et al.¹ showed that Heisenberg uncertainty principle can be used for secret key establishment. The idea of quantum cryptography is that if a third party tries to measure a quantum communication channel, it necessarely disturbs it, provided the bits are coded in incompatible states. This disturbance can be monitored by observing correlations between the in and out going signals.

© 1996 IEEE