A Non-Centralized Routing Scheme with Phase-Caching CDR for Nanosecond-Level Optical Switching Systems.

Optical packet switching (OPS) networks are emerging as a promising solution to overcome the inherent bandwidth limitations of electrical switches in data center networks. However, the practical deployment of nanosecond OPS networks remains a significant challenge due to the lack of efficient optical switch control mechanisms and the difficulty in implementing efficient and fast clock and data recovery (CDR) circuits. In this paper, we experimentally demonstrate a non-centralized congestion control for the phase-caching OPS network. The OPS network comprises four scheduled tunable lasers, an arrayed waveguide grating router (AWGR), and four FPGA-based transceivers. By tuning the four wavelengths in a fixed order, each node communicates with the other four nodes equally and cyclically, ensuring contention-free transmission with equal bandwidth. To maximize the utilization of interconnection bandwidth, high-traffic pairs can exploit low-traffic nodes as intermediate nodes to forward the packets. In the 20.4Gbps transmission test, the four-node OPS network achieved a remarkable 12.8ns end-to-end configuration, with a bit-error rate of 9.8E-10.