Chaos key update using constellation selection and clustering for data centers

Key updating in data centers (DCs) is essential, but it presents challenges related to the consumption of channel resources. To address this issue, we propose a chaos key update scheme using constellation selection and clustering for DCs. At the transmitter side (DC1), the keys to be transmitted are encrypted by generating a digital chaotic sequence using a 4D hyperchaotic system to obtain encryption keys (EK). Then, different constellation mapping rules in the constellation mapping space are used to embed the EK. On the receiving side (DC2), the constellation mapping rules are judged by the mean shift clustering algorithm to assist the extraction of EK, which successfully improves the accuracy of the judgment. These results show that this scheme can safely transmit 70.59 Gb/s power division multiplexing-based discrete multi-tone (PDM-DMT) signal and 1.17 Gb/s error-free key over a 25 km fiber. This scheme realizes the flexible update of the key and enhances the ability to resist potential attacks, thus providing a reliable scheme for the physical layer key update.