Elastic optical networks: The global evolution to software configurable optical networks

Abstract

Worldwide operator deployment of high‐speed 100G coherent optical networks is currently underway. To ensure a competitive solution offering significant performance improvements to cope with the ever‐increasing traffic demand, a novel network concept has been proposed for improved resource utilization based on “elasticity”; specifically, the ability to make a number of previously fixed transmission parameters tunable, for example optical data rate or channel spacing. The benefits are numerous, including increased network capacity, lower cost per bit, and improved energy efficiency and scalability. In this paper, we review the work carried out within the Cooperation for a Sustained European Leadership in Telecommunications (CELTIC) Elastic‐Optical NETwork (EO‐Net) project towards advancing the state of software‐configurable optical networking. We identify the key building blocks for enabling elastic optical networks to provide desired performance improvements over static optical networks. We examine the design of elastic transponders capable of data rate adaptation, interfaces between client packet devices and transponders supporting flexible traffic aggregation, and associated algorithms for traffic grooming and routing. We also perform network cost/energy analyses. Finally, we review the experimental demonstration of such elastic functionalities. © 2013 Alcatel‐Lucent.

Generalized Maximum Likelihood for Cross-Polarization Modulation Effects Compensation

“…For a Qfactor target of 8.5 dB (i.e., a BER of 4 × 10 −3 ), NPCC with average length of 6 shows a 0.5 dB SNR improvement compared to Ref whereas GML with P = 6 has a gain of 0.9 dB. The performance gap also increases for larger Q-factors, i.e., the 1 The non-regularized GML solution corresponds to the case where the regularization factor is null (i.e., γ = 0) in (6). This results in a closed-form solution of each XPolM crosstalk coefficient given by:…”

“…Optical nonlinearities arise then, producing distortions which, in return, limit this optical power level below a certain threshold. The optical reach is therefore significantly reduced with high order modulations, for instance moving from QPSK to 16 QAM doubles the data rate but at the same time reduces the optical reach by a factor of 5 [1]. To gain in performance, the compensation of nonlinear effects becomes of key interest.…”

Design Tradeoffs and Challenges in Practical Coherent Optical Transceiver Implementations

“…However, notice that BICM-2 achieves a better performance than the LC-CM-based solution. Taking into account that the implementation complexities of LC-CM and the high OHbased BICM solutions used in these simulations are similar, we conclude that LC-CM may not be useful in these applications 6 .…”

“…The latter functionality is a fundamental aspect of reconfigurable transceivers, which are D. A. Morero key components of software defined optical networks (SDON) [6], [7].…”

Hardware-programmable optical networks

“…Elastic optical networks (EON) promise to remove the grid limitation in the fixed grid DWDM network and to provide variable optical bandwidths for different link requests [9]. The dynamic bandwidth provisioning helps improve network spectral utilization and also improve network performance in blocking probability and spectrum saving [10].…”