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Antonio Caballero,
Juan Carlos Aguado,
Robert Borkowski,
Silvia Saldaña,
Tamara Jiménez,
Ignacio de Miguel,
Valeria Arlunno, Ramón J Durán,
Darko Zibar,
Jesper B Jensen,
Rubén M Lorenzo,
Evaristo J Abril,
Idelfonso Tafur Monroy
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ABSTRACT: The impact of physical layer impairments in optical network design and operation has received significant attention in the last years, thereby requiring estimation techniques to predict the quality of transmission (QoT) of optical connections before being established. In this paper, we report on the experimental demonstration of a case-based reasoning (CBR) technique to predict whether optical channels fulfill QoT requirements, thus supporting impairment-aware networking. The validation of the cognitive QoT estimator is performed in a WDM 80 Gb/s PDM-QPSK testbed, and we demonstrate that even with a very small and not optimized underlying knowledge base, it achieves between 79% and 98.7% successful classifications based on the error vector magnitude (EVM) parameter, and approximately 100% when the classification is based on the optical signal to noise ratio (OSNR).
Optics Express 12/2012; 20(26):B64-70. · 3.59 Impact Factor
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ABSTRACT: A new multipurpose genetic algorithm, based on Pareto optimality, is proposed to design logical topologies for wavelength-routed
optical networks with the aim of minimizing both the congestion and the end-to-end delay. Simulation results show its efficiency
when compared with other previously proposed algorithms, achieving in most cases optimal or near-optimal solutions, and in
less time than other methods. Moreover, since the algorithm relies on Pareto optimality, not only does it obtain a single
logical topology but a set of them, so that the network designer can easily select the most appropriate one according to the
current network requirements.
Photonic Network Communication 04/2012; 18(3):334-344. · 0.49 Impact Factor
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ABSTRACT: A novel interleaved polling algorithm for Long-Reach EPONs is proposed in order to simultaneously provide subscriber and class
of service differentiation. It is demonstrated that the new polling algorithm applied to a typical 100km Long-Reach EPON
performs better than centralized methods, where bandwidth prediction is needed to overcome the higher round trip time in which
ONUs cannot transmit. As polling methods in Long-Reach EPONs do not require prediction, they are much simpler and show less
computational complexity than centralized schemes, avoiding the inaccuracy of bandwidth prediction. Simulation results show
that the new algorithm increases the achieved throughput when compared to centralized algorithms with traffic prediction,
obtaining a significant reduction of both mean packet delay and packet loss ratio for the highest priority service level profiles.
KeywordsLong-Reach-Passive optical network (PON)-Dynamic bandwidth allocation (DBA)-Service level agreement (SLA)-Class of service (CoS)-Ethernet
Photonic Network Communication 04/2012; 19(3):257-264. · 0.49 Impact Factor
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European Transactions on Telecommunications. 01/2011; 22:35-44.
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Access Networks - 5th International ICST Conference on Access Networks, AccessNets 2010 and First ICST International Workshop on Autonomic Networking and Self-Management in Access Networks, SELFMAGICNETS 2010, Budapest, Hungary, November 3-5, 2010, Revised Selected Papers; 01/2010
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EURASIP J. Adv. Sig. Proc. 01/2010; 2010.
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EURASIP J. Wireless Comm. and Networking. 01/2010; 2010.
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ABSTRACT: In this article, a new dynamic bandwidth allocation algorithm for the upstream channel of Ethernet Passive Optical Networks,
called DySLa, is proposed not only to provide service differentiation but also to offer subscriber differentiation. In contrast
to previous methods in which the performance of each class of service is not insured, DySLa is continuously evaluating the
mean packet delay and guarantees that the highest priority services fulfil the packet delay requirements in the access network
for every type of client. Simulation results show that DySLa can maintain both the mean packet delay and packet loss ratio
below the maximum upper bounds permitted for the most sensitive services of every class of customer. Moreover, DySLa outperforms
other dynamic bandwidth allocation algorithms which provide service and client differentiation and it makes a fairer bandwidth
distribution than those methods.
Photonic Network Communication 03/2009; 17(2):119-128. · 0.49 Impact Factor
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ABSTRACT: A new method to design logical topologies based on genetic algorithms is presented. Not only does the algorithm determine
which nodes should be connected by means of lightpaths with the aim of minimizing congestion, but it also solves the routing
and wavelength assignment problem. In this way, the algorithm guarantees that the logical topology obtained can be embedded
in the optical network subject to the available set of resources. The algorithm is effective in terms of both congestion and
fairness. For instance, when compared with other work, the congestion is significantly reduced (from 20% to 75% depending
on the matrix of traffic considered), and the fairness, when evaluated in terms of the Jain index, is generally higher than
0.94. Moreover, the algorithm brings advantages when employed in dynamic scenarios where the logical topology is frequently
reconfigured, as it is fast and, in contrast to other algorithms previously proposed, the calculation process can be stopped
at any time (if required) in order to give the best virtual topology found up to the moment.
Photonic Network Communication 01/2009; 17(1):21-33. · 0.49 Impact Factor
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Access Networks, 4th International Conference, AccessNets 2009, Hong Kong, China, November 1-3, 2009, Revised Selected Papers; 01/2009
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Optical Network Design and Modeling, 11th International IFIP TC6 Conference, ONDM 2007, Athens, Greece, May 29-31, 2007.; 01/2007
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ABSTRACT: que para el estudio de TCP sobre OBS no basta con considerar un único cliente y servidor, y que TCP y OBS son tecnologías compatibles, siempre que la red OBS se dimensione correctamente.
