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Traffic Grooming in Optical Networks
Published in Partha Pratim Sahu, Advances in Optical Networks and Components, 2020
The formulation of the traffic-grooming problem is discussed in this chapter. For a network configuration, each edge is treated as a physical link, and there are a number of transceivers at each node, number of wavelengths on each fiber, and the capacity of each wavelength, and a set of connection requests with different bandwidth granularities, such as OC-12, OC-48 [3], etc. Here, the setting up of light paths for accommodating the connection requests is carried out by routing and wavelength assignment (RWA) with traffic grooming. Because of the sub-wavelength granularity of the connection requests, more connections are set up via multiplexing on the same light path.
A foresighted measure for RWA algorithms in all-optical mesh networks
Published in Khaled Habib, Elfed Lewis, Frontier Research and Innovation in Optoelectronics Technology and Industry, 2018
Xuhong Li, Junling Yuan, Lihua Yang
Nowadays, all-optical mesh networks, based on the dense wavelength division multiplexing (DWDM) technology and optical cross connections (OXCs), are becoming the main structure of the core transport networks. Wavelength routing is the main method to transfer traffics between nodes and which lead the routing and wavelength assignment (RWA) problem to be a key issue in all-optical mesh networks.
Routing and wavelength assignment with protection: A quadratic unconstrained binary optimization approach enabled by Digital Annealer technology
Published in IISE Transactions, 2023
Oylum Şeker, Merve Bodur, Hamed Pouya
In this study, we consider the routing and wavelength assignment problem with protection, RWA-P. Through complexity analysis and computational experiments, we show that this problem is difficult to solve both in theory and practice. We propose a viable approach, formulating RWA-P as a QUBO model and employing the DA, as a new promising solution technology and test its performance in comparison to exact and heuristic methods. Even though it is not possible to directly impose a time limit for DA, we adjusted the input number of iterations to achieve the desired run times, which typically do not depend on the size of the problem instance. We find that the proposed approach outperforms established methods in handling our nontrivial set of test instances by delivering solutions within 2 minutes that are superior to or as good as the ones other methods yield in 2 hours, as well as two heuristic methods from the literature. Also considering that future generations of DA are planned to achieve megabit-class performance (Fujitsu Limited, 2020b) and offer higher coefficient precision (Nakayama et al., 2021) which can remedy the current limitation on parameter value ranges, we believe that the proposed approach has potential to be utilized widely in practice. As such, future research directions involve considering large-scale cases of RWA-P, adaptation and application of this emerging approach to other RWA problems.
An offline scheme for reducing cost of protection in all-optical WDM mesh networks with fast recovery
Published in International Journal of Parallel, Emergent and Distributed Systems, 2019
Vishal Dey, Abhishek Bandyopadhyay, Uma Bhattacharya, Monish Chatterjee
The work [5] proposes an approach of survivable routing for SSP in mesh WDM networks with nodes having partial wavelength conversion facility. The authors [6] study the problem of Routing and Wavelength Assignment (RWA) of lightpaths while employing SSP in all-optical networks. In [7], the researchers study SSP under the Generalized Multi-Protocol Label Switching based recovery framework and proposes a routing algorithm for SSP. SSP schemes can however be less efficient in terms of backup capacity sharing due to absence of wavelength conversion in all-optical networks. In [4] the authors propose an online protection scheme named streams that incorporate the combined benefits of both DPP and SPP to provide fast and capacity efficient protection from all single link and single node failures. The work [8] extends the streams approach [4] in order to make it more resource-efficient and proposes an offline protection scheme named generalized streams. Researchers [23] propose a protection scheme called mixed SPP for studying the problem of survivable routing to prevent single link failure where some primary and backup paths are allowed to share common mixed resources.
Traffic Grooming in PCE-based Architecture Combined with RWA Utilizing Dynamic Fiber State Information
Published in IETE Technical Review, 2018
The scope of this research work is to verify the performance of the proposed TGA with existing routing and wavelength assignment (RWA) techniques. Therefore, much emphasis has not been given to RWA techniques in the paper as this topic has been greatly researched. Hence, the standard dynamic RWA techniques like First Fit and Random Fit [9] have been incorporated with the algorithm in the simulation process to demonstrate the performance of the proposed TGA in comparison to other existing information scheduling algorithms. Further existing algorithms such as Open Shortest Path First-Traffic Engineering (OSPF-TE) [3], as used in MPLS and GMPLS networks, would be utilized to find the optimum path in the network for the service request.