Autonomous and Energy Efficient Lightpath Operation Based on Digital Subcarrier Multiplexing

Abstract

The massive deployment of 5G and beyond will require high capacity and low latency connectivity services, so network operators will have either to overprovision capacity in their transport networks or to upgrade the optical network controllers to make decisions nearly in real time; both solutions entail high capital and operational expenditures. A different approach could be to move the decision making toward the nodes and subsystems, so they can adapt dynamically the capacity to the actual needs and thus reduce operational costs in terms of energy consumption. To achieve this, several technological challenges need to be addressed. In this paper, we focus on the autonomous operation of Digital Subcarrier Multiplexing (DSCM) systems, which enable the transmission of multiple and independent subcarriers (SC). Herein, we present several solutions enabling the autonomous DSCM operation, including: i) SC quality of transmission estimation; ii) autonomous SC operation at the transmitter side and blind SC configuration recognition at the receiver side; and iii) intent-based capacity management implemented through Reinforcement Learning. We provide useful guidelines for the application of autonomous SC management supported by the extensive results presented.

Packet Flow Capacity Autonomous Operation Based on Reinforcement Learning

“…Each traffic configuration is the combination of traffic pattern and variance. Two different daily patterns were considered: a simple sinusoidal pattern for offline training purposes, and a realistic pattern [16] to emulate the real traffic in the forwarding plane. In both cases, traffic fluctuates between 5 Gb/s (valley) and 40 Gb/s (peak) throughout the day.…”

“…The authors of [15] studied the application of several deep RL algorithms (including DQN) and reward functions to increase network availability in SDN-controlled wide area networks. In the context of IBN, the work in [16] applied Q-learning to the autonomous operation of optical connections based on subcarrier multiplexing. Their RL algorithm, running in the optical transponder, activated and deactivated subcarriers to adapt the capacity of the optical connection to the upper layer packet traffic.…”

Point-to-Multipoint Optical Networks Using Coherent Digital Subcarriers

“…The cited works demonstrate that an optimized (lower) symbol rate can reduce the impact of nonlinearities during fiber propagation. DSCM has also been proposed as a way of increasing tolerance against filter cascade by adapting the order of the modulation format used in individual SCs [42] and to reduce power consumption [43].…”

“…The use of DSCM in P2P mode for high capacity links or breakout P2MP mode for lower capacity links. Leveraging flexible software management of individual SCs, capacity can be instantaneously adapted to bandwidth requirements, turning off blocks associated with unused SCs in the DSP and resulting in OPEX savings[43].…”

Digital Subcarrier Multiplexing: Enabling Software-Configurable Optical Networks

“…Finally, with the possibility of fine-tuning the spectrum, DSCM-based software-configurable optical networks can enable Bandwidth (BW) allocation on demand when and where needed, mimicking statistical multiplexing [30].…”