Self-learning approaches for real optical networks

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Self-learning approaches to facilitate the deployment of ML algorithms in real networks are analyzed and their performance evaluated through an illustrative use case. Results show large benefits of collective self-learning with centralized retraining.Peer ReviewedPostprint (author's final draft

Learning life cycle to speed up autonomic optical transmission and networking adoption

Autonomic optical transmission and networking requires machine learning (ML) models to be trained with large datasets. However, the availability of enough real data to produce accurate ML models is rarely ensured since new optical equipment and techniques are continuously being deployed in the network. One option is to generate data from simulations and lab experiments, but such data could not cover the whole features space and would translate into inaccuracies in the ML models. In this paper, we propose an ML-based algorithm life cycle to facilitate ML deployment in real operator networks. The dataset for ML training can be initially populated based on the results from simulations and lab experiments. Once ML models are generated, ML retraining can be performed after inaccuracies are detected to improve their precision. Illustrative numerical results show the benefits of the proposed learning cycle for general use cases. In addition, two specific use cases are proposed and demonstrated that implement different learning strategies: (i) a two-phase strategy performing out-of-field training using data from simulations and lab experiments with generic equipment, followed by an in-field adaptation to support heterogeneous equipment (the accuracy of this strategy is shown for a use case of failure detection and identification), and (ii) in-field retraining, where ML models are retrained after detecting model inaccuracies. Different approaches are analyzed and evaluated for a use case of autonomic transmission, where results show the significant benefits of collective learning.Peer ReviewedPostprint (published version

Predictive autonomic transmission for low-cost low-margin metro optical networks

Low-cost low-margin implementation plays an essential role in upgrading optical metro networks required for future 5G ecosystem. In this regard, low-resolution analog-to-digital converters can be used in coherent optical transponders to reduce cost and power consumption. However, the resulting transmission systems become more sensitive to physical layer fluctuations like the events caused by fiber stressing. Such fluctuations might have a strong impact on the quality of transmission (QoT) of the signals. To guarantee robust operation, soft decision forward error correction (FEC) techniques are required to guarantee zero post-FEC bit error rate (BER) transmission, which could increase the power consumption of the receiver and thus operational expenses. In this paper, we aim at minimizing power consumption while keeping zero post-FEC errors by means of a predictive autonomic transmission agent (ATA) based on machine learning. We present a sophisticated ATA model that, taking advantage of real-time monitoring of state of polarization traces and the corresponding pre-FEC BER, predicts the right FEC configuration for short-term operation, thus requiring minimum power consumption. In addition, we propose a complementary long-term prediction of excessive pre-FEC BER to enable remote reconfiguration at the transmitter side through the network controller. A set of experimental measurements is used to train and validate the proposed ATA system. Exhaustive numerical analysis allows concluding that ATA based on artificial neural network predictors achieves the maximum QoT robustness with 80% power consumption reductions compared to static FEC configuration.The research leading to these results has received funding from the European Commission for the H2020-ICT-2016-2 METRO-HAUL project (G.A. 761727), from the AEI/FEDER TWINS project (TEC2017-90097-R), and from the Catalan Institution for Research and Advanced Studies (ICREA).Peer ReviewedPostprint (author's final draft

Monitoring and data analytics-triggered reconfiguration in partially disaggregated optical networks

©2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.We present ADONIS, which stands for Aggregator/Disaggregator for Optical Network equIpmentS, a novel open device agent able to construct logical network devices from (dis)aggregation of physical components in order to expose meaningful network devices to the SDN controller. We experimentally assess it by means of a control closed-loop involving ADONIS, a Software Defined Network controller, a Monitoring and Data Analytics system, and a novel reconfiguration tool, SMART-A.The research leading to these results has received funding from the EC through the METRO-HAUL (G.A. nº 761727).Peer ReviewedPostprint (author's final draft

Demonstration of monitoring and data analytics-triggered reconfiguration in partially disaggregated optical networks

©2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.We demonstrate a novel agent for optical disaggregated optical networks. When the Monitoring and Data Analytics detects a degradation, it recommends the SDN controller to trigger a network reconfiguration computed by a novel planning tool.The research leading to these results has received funding from the EC through the METRO-HAUL (G.A. nº 761727).Peer ReviewedPostprint (author's final draft

Optical terabit transmitter and receiver based on passive polymer and InP technology for high-speed optical connectivity between datacenters

We demonstrate the hybrid integration of a multi-format tunable transmitter and a coherent optical receiver based on optical polymers and InP electronics and photonics for next generation metro and core optical networks. The transmitter comprises an array of two InP Mach-Zehnder modulators (MZMs) with 42 GHz bandwidth and two passive PolyBoards at the back- and front-end of the device. The back-end PolyBoard integrates an InP gain chip, a Bragg grating and a phase section on the polymer substrate capable of 22 nm wavelength tunability inside the C-band and optical waveguides that guide the light to the inputs of the two InP MZMs. The front-end PolyBoard provides the optical waveguides for combing the In-phase and Quadrature-phase modulated signals via an integrated thermo-optic phase shifter for applying the pi/2 phase-shift at the lower arm and a 3-dB optical coupler at the output. Two InP-double heterojunction bipolar transistor (InP-DHBT) 3-bit power digital-to-analog converters (DACs) are hybridly integrated at either side of the MZM array chip in order to drive the IQ transmitter with QPSK, 16-QAM and 64-QAM encoded signals. The coherent receiver is based on the other side on a PolyBoard, which integrates an InP gain chip and a monolithic Bragg grating for the formation of the local oscillator laser, and a monolithic 90° optical hybrid. This PolyBoard is further integrated with a 4-fold InP photodiode array chip with more than 80 GHz bandwidth and two high-speed InP-DHBT transimpedance amplifiers (TIAs) with automatic gain control. The transmitter and the receiver have been experimentally evaluated at 25Gbaud over 100 km for mQAM modulation showing bit-error-rate (BER) performance performance below FEC limit

Absorption à deux photons et effets de corrélation quantique dans les semiconducteurs

en français : Les corrélations de photons sont à la base d'un certain nombre d'expériences et d'applications (spectroscopie de corrélation de photons, profilométrie haute résolution, cryptographie quantique, téléportation). L'évaluation de ces propriétés de corrélation revêt dès lors une importance toute particulière et correspond à la thématique dans laquelle s'inscrit ce travail de thèse de Doctorat. Tout d'abord, les concepts de compteur de photons par absorption à deux photons ont été (ré)évalués expérimentalement dans différents semiconducteurs et nous ont conduits à établir les bases d'un modèle quantique du comptage à deux photons. Par la suite, l'absorption à deux photons dans les semiconducteurs est appliquée dans une nouvelle technique qui permet la mesure du degré de cohérence d'ordre deux de sources optiques continues de faibles puissances (0,1 W au minimum) avec une bande passante allant de 1,1 à 1,7 m et une résolution de l'ordre de la femtoseconde. Expérimentalement, le montage est conceptuellement proche d'un interféromètre de Hanbury Brown et Twiss où, dans notre cas, les deux sous-faisceaux décalés dans le temps sont recombinés sur un compteur à deux photons. Grâce à la très large bande passante à deux photons, les corrélations de sources larges spectralement sont caractérisées au moyen de ce montage qui permet la mesure du degré de cohérence d'ordre deux de sources chaotiques aussi bien que d'un générateur paramétrique à la dégénérescence ou hors de la dégénérescence. Pour la première fois, le phénomène de bunching des photons issus d'un corps noir a été vérifié par une mesure directe. Pour ce qui est de la lumière paramétrique, après avoir développé une source de photons jumeaux, nous avons démontré que notre montage expérimental était à même de mesurer les coïncidences exactes des photons issus d'une même paire aussi bien que les coïncidences accidentelles entre photons de paires différentes en contrôlant les phénomènes de dispersion chromatiques à l'aide d'une paire de prismes. Enfin, deux modèles théoriques originaux de corrélation de photons jumeaux ont été développés, basées sur les approches quantique et classique, et sont en excellent accord avec l'ensemble de nos résultats expérimentaux.en anglais : Photon correlation properties are now harnessed in various experiments and applications (photon correlation spectroscopy, high resolution profiling, quantum cryptography, quantum teleportation...). The determination of the correlation properties of light is thus of paramount importance and corresponds to the topic investigated in this PhD thesis. Firstly, the semiclassical concept of Two-Photon Counter is experimentally revisited using two photon absorption in various semiconductors and leads to the development of the foundations of an unified two-photon counting theory. Then, two photon conductivity in semiconductors is exploited in a new technique that enables the determination of second order correlation of cw optical sources with output power down to 0.1 W, bandwidth in the 1.1 to 1.7 m range and time resolution in the femtosecond range. Experimentally, the system is similar to a Hanbury Brown & Twiss interferometer but, in our case, the two delayed sub-beams are recombined in a two-photon counting device. Thanks to the huge available bandwidth, broadband source correlations are characterized by measuring, with the same apparatus, the degree of second order coherence of chaotic sources or optical parametric generator (both degenerate and non degenerate cases). For the first time, the bunching effect in a real blackbody is unambiguously shown down to the femtosecond level. Concerning parametric light, after developing down converted source, we demonstrate that our experimental set-up is able to determine the exact coincidence of twin photon as well as the accidental one between photons from different pairs by controlling chromatic dispersion phenomena with a prism pair set-up. Finally, two theoretical modeling of twin photons correlation were developed, based on a full quantum theory of two multimodal-photon interaction and a classical stochastic field approach, and are both in excellent agreement with all our experimental results.PALAISEAU-Polytechnique (914772301) / SudocSudocFranceF

Collective self-learning by exchanging ML models

Collective self-learning based on Machine Learning (ML) model sharing and combination is proposed to accelerate ML-based algorithm deployment. The considered architecture is presented, together with different alternatives for combining ML models. Performance analysis is carried out on an illustrative use case for autonomic optical transmission.The research leading to these results has received funding from the AEI/FEDER TWINS project (TEC2017-90097-R), from the EC METRO-HAUL project (G.A. nº 761727), and from the Catalan ICREA Institution.Peer ReviewedPostprint (author's final draft