Polatis (United Kingdom)

This paper proposes and experimentally evaluates a fully developed novel architecture with purpose built low latency communication protocols for next generation disaggregated data centers (DDCs). In order to accommodate for capacity and latency needs of disaggregated IT elements (i.e., CPU, memory), this architecture makes use of a low latency and high-capacity circuit-switched optical network for interconnecting various end points that are equipped with multi-channel silicon photonic based integrated transceivers. In a move to further decrease the perceived latency between various disaggregated IT elements, this paper proposes a novel network topology that cuts down the latency over the optical network by 34% while enhancing system scalability and channel bonding over multi-core fiber (MCF) switched links to reduce head to tail latency and in turn increase sustained memory bandwidth for disaggregated remote memory. Furthermore, to reduce power consumption and enhance space efficiency, the integration of novel MCF-based transceivers, fibers, and optical switches are proposed and experimentally validated at the physical layer for this topology. It is shown that the integration of MCF-based subsystems in this topology can bring about an improvement in energy efficiency of the optical switching layer, which is above 60%. Finally, the performance of this proposed architecture and topology is evaluated experimentally at the application layer where the perceived memory throughput for accessing remote and local resources is measured and compared using electrical circuit and packet switching. The results also highlight a multi-fold increase in application perceived memory throughput over the proposed DDC topology by utilization and bonding of multiple optical channels to interconnect disaggregated IT elements that can be carried over MCF links.

The papers in this special section focus on photonic networks and devices. These papers address the challenges and enabling technologies for high-performance optical networks, encompassing cutting-edge photonic devices, ultra-high capacity transmission systems, flexible and scalable network architecture, and cutting-edge network management paradigms leveraging on machine learning and SDN/NFV. It also serves as an archive of the key contributions presented at the OSA Photonic Networks and Devices (NETWORKS’18) meeting held at ETH Zurich in Switzerland, 2–5 July 2018, along with the distinguished papers accepted from an open call.

Forward error correction (FEC) based on Reed–Solomon coding for the burst-mode upstream traffic of passive optical networks (PONs) is analyzed in detail using flexible field-programmable gate arrays (FPGAs). In order to achieve true burst-mode transmission using FPGAs, specific architectural solutions are required. In particular, a burst-mode frame synchronizer and a burstmode Reed–Solomon decoder are described in detail and analyzed experimentally within a state-of-the-art longreach PON test-bed. During this analysis, the upstream FEC performance is impaired by introducing strongly correlated and localized errors within the burst through the reduction of the burst preamble duration. The observed FEC degradation is exhaustively analyzed by implementing on the FPGAs a tool for error location analysis and frame loss measurements. This investigation demonstrates the importance of understanding the error distribution within the burst in order to correctly estimate the FEC performance in PON upstream links.

This paper demonstrates a FPGA-based network interface with reconfigurable switched ports that access to disaggregated resources. Silicon-Photonics on-board transceivers and miniaturized optical switches deliver bandwidth density and FEC-free scalability of up to 5-tier network.

We present recent efforts for developing “greener” and future-proofed communication networks by employing reflective architectures in the metro edge and access parts of the network. Colourless and coolerless reflective photonic integrated circuits are used in combination with high port-count optical switches for creating costeffective, scalable and dynamic network architectures, delivering 100 Gb/s transport and 10 Gb/s access networks.