Electronic and photonic switching in the atm era

Broadband networks require high-capacity switches in order to properly manage large amounts of traffic fluxes. Electronic and photonic technologies are being used to achieve this objective both allowing different multiplexing and switching techniques. Focusing on the asynchronous transfer mode (ATM), the inherent different characteristics of electronics and photonics makes different architectures feasible. In this paper, different switching structures are described, several ATM switching architectures which have been recently implemented are presented and the implementation characteristics discussed. Three diverse points of view are given from the electronic research, the photonic research and the commercial switches. Although all the architectures where successfully tested, they should also follow different market requirements in order to be commercialised. The characteristics are presented and the architectures projected over them to evaluate their commercial capabilities.Peer ReviewedPostprint (published version

Optical monitoring system for scalable all-optical networks

High traffic and high capacity communications are believed to become cost-effective with the use of all-optical networks based on OFDM (optical frequency division multiplexing). In such networks, new strategies for OA and M (operation, administration and maintenance) functions need to be developed so as to suit the introduction of a new optical layer where in wavelength routing is exploited and faults are detected in a transparent manner. In this paper, we propose a scheme to monitor optical channels in the optical layer for supporting OA and M functions of a transparent and scalable photonic network.Peer ReviewedPostprint (published version

Proactive defragmentation in elastic optical networks under dynamic load conditions

The final publication is available at Springer via http://dx.doi.org/10.1007/s11107-018-0767-7The main weakness of elastic optical networks (EON), under dynamic traffic conditions, stems from spectrum fragmentation. A lot of research efforts have been dedicated during recent years to spectrum defragmentation. In this work, a thorough study about proactive defragmentation is carried out. Effects of the different defragmentation parameters on the EON performance are analyzed, and appropriate values of the defragmentation period, which guarantee suitable network performance while keeping the network control complexity at reasonable values, are obtained by means of extensive simulations. Benefit obtained by applying different defragmentation strategies, in terms of increase in the supported load at a given bandwidth blocking probability, is also reported. Different traffic conditions and network topologies are simulated to assess the validity of the obtained results.Peer ReviewedPostprint (author's final draft

Cross-connection management specialisation for WDM-OTN's

WDM optical transport networks (WDM-OTN) will use new all-optical nodes that will perform functions in the optical domain, using wavelength as a new network resource. This paper presents a new approach for the optical cross-connect (OXC) routing operation that takes into account a diminished connection capability.Peer ReviewedPostprint (published version

Quantifying bypass traffic in partially meshed transparent optical networks

This work investigates the transparent bypassing capacity requirements of elastic backbone optical networks to determine the all-optical cross-connection capacity needed at network nodes. Topological parameters have been used to develop a random network generator, and the generated topologies are evaluated. Reference values are obtained and applied to well-known topologies, and extensive simulations are conducted to obtain network nodes' bypassing traffic under realistic traffic profiles. The study reveals that although bypassing traffic varies by topology, it never exceeds 9% of total network traffic per node degree. These findings can help properly dimension network nodes by determining the necessary quantity of transceivers and cross-connection capacity based on the network topology and expected traffic.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work has been partially funded by Spanish AEI IBON (PID2020-114135RB-I00).Peer ReviewedPostprint (published version

Cancelación del ruido AM en sistemas de transmisión coherentes por fibra óptica: receptor balanceado

In this work the authors have studied the AM noise influence over coherent transmission systems employing heterodyne-type detection. A dual-detector optical heterodyne receiver is also studied in arder to eliminate the LO noise. Finally a comparison between the two schemes has been done.Peer ReviewedPostprint (published version

Acotación de la probabilidad de error en un sistema de transmisión digital por fibra óptica

Dans ce papier, on a obtenu des bornes inférieure et supérieure de la probabilité d 'erreur par symbole dans un systemè de transmission numérique par Fibre Optique. Pour celà, nous avons employé une simplification de la méthode exhaustive qui permet de connaitre, pour chaque message transmis, la valeur de l'interférence intersymboles et du bruit de grenaille. L'approsimation gaussienne sur le bruit de grenaille permet une réduction considérable du temps de calcul. La précision sur la probabilité d'erreur, mesurée par l'écart entre les bornes supérieure et inférieure, augmente avec le nombre de symboles du message numérique pris en compte. Enfin, les résultats obtenus permettent de déterminer l'espacement des répéteurs.Peer ReviewedPostprint (published version

Performance of FH-MFSK serial search synchroniser for mobile radio

Peer ReviewedPostprint (published version

Caracterización estadística del amplificador óptico semiconductor aplicado en un enlace digital por fibra óptica

In this paper an statistical model for the semiconductor optical amplifier CSLA) working in linear regime is developped. This model, based on the STT theory, allows the calculation of any number of moments of the statistical distribution of photons of the amplified light. The validity of the model is shown using as input some different statistical distributions and evaluating their corresponding output distributions.Peer ReviewedPostprint (published version

Modelo estadístico del láser amplificador en un sistema de transmisión digital por fibra óptica monomodo

En este trabajo se obtiene un modelo estadístico del laser amplificador semiconductor y se desarrolla la metodología y el software necesarios para poder obtener resultados analíticos. En definitiva, se consigue conocer la estadística de la luz amplificada por este dispositivo de estado sólido. El número de momentos estadísticos que puede obtenerse depende, únicamente, de la capacidad del ordenador. Pueden entonces evaluarse, mediante la función densidad de probabilidad, el valor medio y la potencia de la información y del ruido cuántico a la salida del laser amplificador para poder analizar, finalmente, las prestaciones introducidas por el mismo en un enlace óptico.Peer ReviewedPostprint (published version