Algorithms for Routing and Spectrum Allocation in Elastic Optical Networks: A Taxonomy

Elastic Optical Networks (EONs) increase the transport capacity of standard optical networks, and have been proposed as a short-term solution to satisfy the dynamic demands of service quality requirements. To this end, the development of algorithms to better facilitate Routing and Spectrum Allocation (RSA) is envisaged to have a critical impact on the performance of EON. Given the abundance of RSA algorithms, this study presents the unique challenge of organizing and classifying them meaningfully to understand and select the most suitable approach for the corresponding niche service quality requirements. This study proposes a novel taxonomy structure for grouping RSA algorithms based on the following criteria: (1) resource assignment policies, (2) flexibility type, (3) traffic type, (4) optimization approaches, (5) number of objective functions, and (6) problem separability. Finally, the contributions of this study are twofold: it presents a state-of-the-art taxonomy framework that organizes existing published works based on a set of predetermined criteria, and explores research opportunities involving RSA algorithms to realize the full potential of EONs in telecommunications.