| Quantum Key Distribution in combination with the one-time pad encryption protocol promises unconditional secure communication. However, current Quantum Key Distribution (QKD) systems distribute keys with low rates, making the implementation of the highly key consuming one-time pad impractical. This thesis describes a detailed characterization of telecommunication components in view of possible use for high rate QKD through telecommunication fibre networks, and a proof-of-principle demonstration of a QKD system using the components studied. Specific problems have been identified, and solutions are suggested. |