The high capacity demand, to support broadband services and everything-to-internet connectivity is pushing the limits of both access and metro networks, requiring the adoption of novel strategies for the optical transceiver modules. This represents an opportunity for the adoption in these network scenarios of novel photonic technologies based on single-mode vertical cavity surface emitting lasers (VCSELs) at long wavelengths. On one hand, the access network evolution requires a line rate increase beyond 10 Gb/s, targeting 50 Gb/s propagation in passive optical networks (PONs) over a few tens of kms in standard single mode fiber (SSMF) with simple, cost effective and energy efficient transceivers. On the other hand, the future metropolitan area network (MAN) will need to handle multi-Tb/s traffic in a very dynamic scenario, over variable distances up to hundreds of kms while promoting sustainability, reducing the CapEx and OpEx costs and power consumption. Both needs can be fulfilled by adopting VCSEL direct modulation with multicarrier modulation formats such as discrete multitone (DMT), in combination with distinct transmitter architectures and receiver solutions to support different aggregate capacity requirements and transmission reaches. In any case DMT with bit/power loading enables flexible rate and adaptive distance for metro network applications and link adaptation and PON resource usage optimization for future access networks. In this work, we report our recent results on the adoption of VCSEL technology in both scenarios, with special focus on the receiver and transmitter adopted architectures.
Innovative photonic solutions designed and developed in the H2020 research project PASSION are presented for the future metropolitan area network (MAN) supporting different aggregated data traffic volumes and operating at heterogenous granularities. System performance evaluated both by simulations and experimentation regarding the proposed vertical cavity surface emitting laser (VCSEL) -based modular sliceable bandwidth/bitrate variable transceiver (S-BVT) are shown in realistic MANs organized by hierarchical levels with the crossing of multiple nodes characterized by new switching/aggregation technologies. The capabilities and challenges of the proposed cost-effective, energy-efficient and reduced footprint technological solutions will be demonstrated to face the request of huge throughput and traffic scalability.
The information technologies (ITs)-communications infrastructure convergence is key to future optical networks for achieving an automated orchestration of IT, optical and cloud resources. To cope with this challenge, transmission systems need to be agile, programmable, and capable of transmitting large amounts of data, while covering data center and metropolitan networks. This work addresses transmission solutions using coherent detection combined with either direct or external modulation, with special focus on flexible, high capacity and cost/energy-efficient systems. The proposed technological solutions are evaluated in terms of throughput, and programmability and interaction with the control plane.