This thesis covers the basics of cryptography, both classical and the newer quantum-basedapproches. Further, it details an implementation of a BB84-based quantum key distributionsystem currently under construction, focusing on the controlling hardware and FPGA-basedsoftware. The overarching goal is to create a system impervious to currently known attackson such systems. The system is currently running at 100 Mbit/s, though the goal is to double this asthe design nears its completion. The system currently chooses encoding base, bit value andwhether a state is a socalled decoy state. However, the modulator for bit encoding is notyet operational. Output for decoy state generation, however, is fully functional. Finally, the thesis describes what steps are necessary to reach a complete BB84-basedquantum key distribution system implementing decoy states.