SDN-controlled and Orchestrated OPSquare DCN Enabling Automatic Network Slicing with Differentiated QoS Provisioning

In this work, we propose and experimentally assess the automatic and flexible NSs configurations of optical OPSquare DCN controlled and orchestrated by an extended SDN control plane for multi-tenant applications with differentiated QoS provisioning. Optical Flow Control (OFC) protocol has been developed to prevent packet losses at switch sides caused by packet contentions.Based on the collected resource topology of data plane, the optical network slices can be dynamically provisioned and automatically reconfigured by the SDN control plane. Meanwhile, experimental results validate that the priority assignment of application flows supplies dynamic QoS performance to various slices running applications with specific requirements in terms of packet loss and transmission latency. In addition, the capability of exposing traffic statistics information of data plane to SDN control plane enables the implementation of load balancing algorithms further improving the network performance with high QoS. No packet loss and less than 4.8 us server-to-server latency can be guaranteed for the sliced network with highest priority at a load of 0.5

Multi-Wavelength, Multi-Level Inputs for an All-Optical SOA-Based Neuron

We demonstrate the first optical processing of up to 9-bit/symbol multi-level modulated channels on a complete all-optical SOA-based neuron, with an error of 0.08. A higher number of modulation levels and inputs can improve accuracy

Performance assessment of OPSquare data center network with elastic allocation of WDM transceivers

Under realistic OPSquare data center traffic model, the impact of the packet loss ratio and sever end-to-end latency of elastic allocation of WDM transmitters at top of rack (ToR) is numerically investigated. Results show that with limited 50 KB buffer, a sever end-to-end latency lower than 2 μs and packet loss ratio below 10-6 could be guaranteed for different traffic patterns and loads when the WDM transmitters at ToRs are adaptively allocated. An analyses on costs and power consumption indicate that the elastic allocation of WDM transmitters will not cause dramatic fluctuation in power consumption, while cost will increase with more usage of transmitters

Precise Time Distribution and Synchronization for Low Latency Slotted Optical Metro-Access Networks

Future optical metro access networks will connect heterogeneous access technologies like beyond 5G radio access networks and edge computing interconnections. These access networks and their diversified use cases will impose significant challenges on network capacity, wavelength resource and network synchronization. In this paper, we present and investigate a novel time slotted optical metro access network controlled by a multifunctional supervisory channel for precise time distribution, nodes synchronization, and fast wavelength reusing to improve the overall network performance for low and deterministic latency applications. The supervisory channel carries timestamps of different nodes in different time slots, and the labels with the data channels destinations in every time slot. By analyzing the supervisory channel at each node, the timestamps and add/drop information can be precisely and fast exchanged. A network testbed has been implemented for assessing the proposed network operation and precise time synchronization. The results show successful time slotted network operation, 82% of bandwidth usage and 2.5 s latency have been achieved. Below 12 ns time accuracy has been measured for a metro ring and 5G front haul network with a single time reference. To assess the scalability and wavelength saving of the proposed network in a larger network, a simulation model has been developed in OMNeT++ based on the experimental parameters. Numerical results show more than 16 % wavelengths can be saved by our technology compared with Cloud Burst Optical-Slot Switching (CBOSS)[1]

Noise and Scalability Investigation of SOA-based All-optical Photonic Deep Neural Network

We emulate and experimentally validate the scaling of SOA-based all-optical deep neural networks by accurately modeling the OSNR degradation in a chain of SOAs: The photonic neural network can scale up to 16 layers when using only 4 neurons/layer without notable accuracy degradation

Noise analysis of SOA-based All-optical Photonic Deep Neural Network with WDM input

We experimentally verify the noise modeling of SOA-based all-optical neural networks on the OSNR degradation of the neuron: The photonic neural network can scale up to 16×16 neurons per layer, resulting in NRMSE <0.10

Flexibility assessment of the reconfigurable OPSquare for virtualized data center networks under realistic traffics

Resources allocation of the reconfigurable OPSquare data center to support multi-tenant virtual networks are assessed under realistic traffics. End-to-end latency < 2μ s and packet loss <10 -4 are guaranteed for different traffic patterns by elastically configuring the WDM transmitters and optical switches

Experimental Assessment of Automatic Optical Metro Edge Computing Network for Beyond 5G Applications and Network Service Composition

The upcoming 5G and beyond 5G heterogeneous applications with different quality of service (QoS) will impose strict latency, bandwidth, and flexibility requirements on optical metro access networks. Conventional cloud computing is gradually unable to fulfill the application requirements, especially on latency due to the distance causing propagation and networking delay. Therefore, the edge computing that distributed in metro access networks is promising to serve the applications with the requirements of ultra-low latency. As the resources of edge computing nodes are restricted and light compared with cloud data centers (DC), it is significant to manage across multiple edge computing nodes to enable joint allocation of the distributed resources. To address this issue, the optical metro network infrastructure should be flexible on the data plane and able to interact with the control and orchestration plane to automatically adapt to the communication requirements of multiple edge computing nodes. Related works have been focused on the simulation and numerical study. In this paper, an experimental testbed of a flexible optical metro access network including hardware and software components is built, and the performance is validated with real server traffic. The presented network system is based on the field-programmable gate array (FPGA), and hardware adapted open source network management and telemetry tools. Different from the commercial electrical switches, FPGA is fully programmable making it able to flexibly forward and monitor the traffic, in the meantime, to dynamically control the optical devices according to the feedback from the control plane. By exploiting dynamic software defined networking (SDN) control and network service orchestration, the proposed network is able to establish capacity adapted network slices for edge computing connections. Successful telemetry-assisted dynamic network service chain (NSC) generation, automatic bandwidth resources assignment, and QoS protection are demonstrated

Flow-controlled and Clock-distributed Optical Switch and Control System

Switching the traffic in the optical domain has been considerably investigated as a future-proof solution to overcome the intrinsic bandwidth bottleneck of electrical switches in data center networks (DCNs). However, due to the lack of fast and scalable optical switch control mechanism, the lack of optical buffers for contention resolution, and the complicated implementation of fast clock and data recovery (CDR), the practical deployment of fast optical switches in data centers (DCs) remains a big challenge. In this work, we develop and experimentally demonstrate for the first time a flow-controlled and clock-distributed optical switch and control system, implementing 43.4 ns optical switch configuration time, less than 3.0E-10 packet loss rate resulting from the packet contention, and 3.1 ns fast CDR time. Experimental results confirm that zero buffer overflow caused packet loss and lower than 3μs server-to-server latency are achieved for network deploying a smaller electrical buffer of 8192 bytes at a traffic load of 0.5. Real servers running the Transmission Control Protocol (TCP) traffic generating and monitoring tools are exploited in this switch and control system as well, validating its capability of running practical DCNs services and applications with full TCP bandwidth