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The Optical Network Emulation (ONE) engine is a real-time, multi-container software platform designed to model and emulate open optical transport networks with realistic fidelity. This paper introduces an enhanced version of the ONE engine that integrates a distributed implementation of a Gaussian Noise (GN) model for estimating nonlinear interference (NLI) in wavelength division multiplexing (WDM) systems. The inclusion of the GN model enables more realistic emulation of nonlinear signal degradation across diverse link configurations and operating conditions. The enhanced ONE package is then used to document the model’s impact on system performance under varying transmission conditions, including signal launched power and increased spectral loading. With this upgrade, the ONE engine expands its utility for research, development, and education, providing a scalable and flexible environment for testing physical-layer impairments and control strategies in software-defined optical networks.
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Physical-layer impairment estimation for arbitrary spectral-shaped signals in optical networks
In long-haul fiber-optic networks, precise modeling of physical-layer impairments (PLIs) is crucial to optimizing network resource usage while ensuring adequate transmission quality. In order to accurately estimate PLIs, many mathematical models have been proposed. Among them, the so-called Gaussian noise (GN) model is one of the most accurate and simple enough to use on complex continental-size networks. However, the closed-form GN model assumes that the signals can be represented as having rectangular spectra, leading to a significant estimation error in typical cases when this assumption is violated. We propose the component-wise Gaussian noise (CWGN) PLI model that can account for arbitrary spectral-shaped demands. The CWGN model is computationally simple and suitable for most network management approaches. Results indicate that the CWGN model can prevent as much as a 136% overestimation of the PLIs resulting from the closed-form GN model applied to network lightpaths containing cascaded filters.
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- Award ID(s):
- 1718130
- PAR ID:
- 10531177
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 30
- Issue:
- 10
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 17351
- Size(s):
- Article No. 17351
- Sponsoring Org:
- National Science Foundation
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