Cryptography Reference
In-Depth Information
Alice
Bob
2 x 2
Optical
Switch
Anna
Boris
Figure 4.9
Current topology of the DARPA Quantum Network.
The switch chosen for this network is a standard telecommunications
facilities switch that operates by moving reflective elements that change the
internal light path to produce either a BAR or a CROSS connection. It is
operated by applying a TTL-level pulse to either the BAR or the CROSS pin for
20 ms and latches in the activated position. Switching time is 8 ms and optical
loss is < 1 dB. Figure 4.10 shows a photograph of the switch mounted on a PC
board with the electrical interconnects on the left and optical interconnects
on the right.
×
Figure 4.10
The 2
2 optical switch mounted on a PC board.
