Optical encryption based on chaos and dense wavelength division multiplexing [DWDM] methods are even more popular. Chaos-based communications provide an approach for transmitting confidential data with a high level of robustness against various types of attacks. It also allows to jam the communication of hackers. In that method, the original data is decomposed into multiple data packages that are encrypted separately. Then, all the packages are multiplexed and compacted into a single package of data. This data is only properly decoded when in possession of the appropriate key to read it. Indeed, only the receiver that has knowledge on how the chaos is generated can reverse the chaos to recover the signal after appropriate filtering and synchronizing procedures applied to the multiplexing.

Since many years, SEDI-ATI has been developing and manufacturing multimode wavelength division multiplexers and optical couplers with very high directivity. SEDI-ATI has designed, built and demonstrated reliable solutions that are currently in the field, such as custom modules implementing those fiber-based components. Today, these reliable and secured modules fully optically isolate strategic data centers.

For a higher security level, fiber-optic quantum key distribution is currently being investigated. Indeed, it could effectively protect the encryption process by encoding the key information on the quantum states of a single photon. Moreover, one important property for quantum key distribution is that it can indicate the existence of an eavesdropper trying to receive any information about the key.

To reply to such a challenge, SEDI-ATI has recently realized fiber optic hermetic feedthroughs and patch-cords dedicated to cryogenic applications which are required for quantum optics cryptography demonstration.