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  • Optimal route, spectrum, and modulation level assignment in split-spectrum-enabled dynamic elastic optical networks

     Pages Cruz, Albert; Perello Muntan, Jordi; Spadaro, Salvatore; Comellas Colome, Jaume
    Journal of optical communications and networking
    Date of publication: 2014-02-01
    Journal article

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    The spectrum fragmentation effect in elastic optical networks is one of their main limitations. Multiple techniques have been proposed to address this problem, with the split spectrum approach (SSA) being a very interesting candidate among them. This technique is based on splitting a demand into smaller sub-demands when a blocking situation arises. In split-spectrum-enabled networks, the route, spectrum, and modulation level assignment (RSMLA) problem that appears in elastic optical networks is further complicated due to the signal splitting operation. In this paper we present novel mechanisms to optimally attack this problem; various possible implementations of the SSA are also discussed. We highlight the benefits of the proposed mechanisms through illustrative results and compare the various implementation solutions in terms of average network cost.

  • Combining Optics and SDN In next Generation data centre Networks COSIGN

     Spadaro, Salvatore
    Participation in a competitive project

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  • All-optical packet/circuit switching-based data center network for enhanced scalability, latency, and throughput

     Perello Muntan, Jordi; Spadaro, Salvatore; Ricciardi, Sergio; Careglio, Davide
    IEEE network
    Date of publication: 2013-12
    Journal article

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    Applications running inside data centers are enabled through the cooperation of thousands of servers arranged in racks and interconnected together through the data center network. Current DCN architectures based on electronic devices are neither scalable to face the massive growth of DCs, nor flexible enough to efficiently and cost-effectively support highly dynamic application traffic profiles. The FP7 European Project LIGHTNESS foresees extending the capabilities of today's electrical DCNs through the introduction of optical packet switching and optical circuit switching paradigms, realizing together an advanced and highly scalable DCN architecture for ultra-high-bandwidth and low-latency server-to-server interconnection. This article reviews the current DC and high-performance computing (HPC) outlooks, followed by an analysis of the main requirements for future DCs and HPC platforms. As the key contribution of the article, the LIGHTNESS DCN solution is presented, deeply elaborating on the envisioned DCN data plane technologies, as well as on the unified SDN-enabled control plane architectural solution that will empower OPS and OCS transmission technologies with superior flexibility, manageability, and customizability.

  • Protocol enhancements for "greening" optical networks

     Morea, Annalisa; Perello Muntan, Jordi; Spadaro, Salvatore; Verchere, Dominique; Vigoureux, Martin
    Bell labs technical journal
    Date of publication: 2013-12
    Journal article

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    The last decade has spurred a number of research efforts around energy efficiency in information and communication technologies (ICT). To reduce the energy consumed by optical transport networks, one option is to switch-off a certain number of optical systems according to the amount of transported traffic. Consequently, dynamic power management of optoelectronic devices and link sleep-mode approaches have been proposed; these capabilities quantitatively optimize the power requirements and the available bandwidth of the network as a whole. This paper presents enhancements embedded in Generalized Multiprotocol Label Switching (GMPLS)-based protocols enabling power control in optical devices, and then analyzes the impact of controlling the daily energy consumption of optical switching equipment in the network. We also present ongoing activities in specific standardization working groups for "greening the network" along with their proposals to improve the energy efficiency of future optical networks. © 2013 Alcatel-Lucent.

  • Advances in optical networks control and management

     Wu, Jing; Wosinska, Lena; Shen, Gangxiang; Spadaro, Salvatore
    Optical switching and networking
    Date of publication: 2013-01
    Journal article

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  • Cost-efficient virtual optical network embedding for manageable inter-data-center connectivity

     Perello Muntan, Jordi; Spadaro, Salvatore; Pavón Mariño, Pablo
    ETRI journal
    Date of publication: 2013-02
    Journal article

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    Network virtualization opens the door to novel infrastructure services offering connectivity and node manageability. In this letter, we focus on the cost-efficient embedding of on-demand virtual optical network requests for interconnecting geographically distributed data centers. We present a mixed integer linear programming formulation that introduces flexibility in the virtual-physical node mapping to optimize the usage of the underlying physical resources. Illustrative results show that flexibility in the node mapping can reduce the number of add-drop ports required to serve the offered demands by 40%.

  • Traffic variation-aware networking for energy efficient optical communications

     Morea, Annalisa; Perello Muntan, Jordi; Spadaro, Salvatore
    International Conference on Optical Network Design and Modeling
    Presentation's date: 2013-04-17
    Presentation of work at congresses

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    'Traffic-aware' networking is a solution allowing the improvement of the energy efficiency of optical networks. The implementation of these networking schemes makes possible to adapt the number of fully powered systems to the amount of carried traffic. Various traffic-aware schemes are available in the literature; some acting on the optical amplifiers, others on the optoelectronic (OE) devices. In this paper we introduce the parameter p to measure the energy savings introduced by a 'traffic-aware' scheme; the savings are obtained by considering the maximum power required to transport the peak traffic and the average power required by the network to transport the traffic during a defined time-frame (e.g. day, week). The higher the p-parameter is, more energy-efficient the 'traffic-aware' solution is. The energy efficiency of three on-off strategies, acting separately and/or jointly to amplifiers and OE-devices, are compared and discussed in terms of management implementation and network resiliency.

    'Traffic-aware' networking is a solution allowing the improvement of the energy efficiency of optical networks. The implementation of these networking schemes makes possible to adapt the number of fully powered systems to the amount of carried traffic. Various traffic-aware schemes are available in the literature; some acting on the optical amplifiers, others on the optoelectronic (OE) devices. In this paper we introduce the parameter p to measure the energy savings introduced by a 'traffic-aware' scheme; the savings are obtained by considering the maximum power required to transport the peak traffic and the average power required by the network to transport the traffic during a defined time-frame (e.g. day, week). The higher the p-parameter is, more energy-efficient the 'traffic-aware' solution is. The energy efficiency of three on-off strategies, acting separately and/or jointly to amplifiers and OE-devices, are compared and discussed in terms of management implementation and network resiliency.

  • Access to the full text
    Link vs. opto-electronic device sleep mode approaches in survivable green optical networks  Open access

     Perello Muntan, Jordi; Morea, Annalisa; Spadaro, Salvatore; Tornatore, Massimo
    Optical Fiber Communication Conference and Exposition and National Fiber Optic Engineers Conference
    Presentation's date: 2013-03-20
    Presentation of work at congresses

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    Energy savings of link and OE device sleep mode approaches are compared in 1:1 protected optical networks, together with a hybrid solution combining both of them. The proposed hybrid solution can decrease network energy consumption by up to 82%.

    Energy savings of link and OE device sleep mode approaches are compared in 1:1 protected optical networks, together with a hybrid solution combining both of them. The proposed hybrid solution can decrease network energy consumption by up to 82%.

  • Control plane architectures for photonic packet/circuit switching-based large scale data centres

     Spadaro, Salvatore
    European Conference on Optical Communication
    Presentation's date: 2013-09-24
    Presentation of work at congresses

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    This invited talk discusses the usage of optical switching capabilities inside data centers.

  • Optimized monitor placement for accurate QoT assessment in core optical networks

     Angelou, Marianna; Pointurier, Yvan; Careglio, Davide; Spadaro, Salvatore; Tomkos, Ioannis
    Journal of optical communications and networking
    Date of publication: 2012-01
    Journal article

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  • Optimized burst LSP design for absolute QoS guarantees in GMPLS-controlled OBS networks

     Pedroso Mendonça, Pedro; Perello Muntan, Jordi; Careglio, Davide; Klinkowski, Miroslaw; Spadaro, Salvatore
    Journal of optical communications and networking
    Date of publication: 2012-02
    Journal article

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  • Experimental demonstration of a GMPLS-enabled impairment-aware lightpath restoration scheme

     Perello Muntan, Jordi; Spadaro, Salvatore; Agraz Bujan, Fernando; Angelou, Marianna; Azodolmolky, Siamak; Qin, Yixuan; Nejabati, Reza; Simeonidou, Dimitra; Kokkinos, Panagiotis; Varvarigos, Emmanouel A.; Tomkos, Ioannis
    Journal of optical communications and networking
    Date of publication: 2012-05
    Journal article

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  • Strategies for virtual optical network allocation

     Pages Cruz, Albert; Perello Muntan, Jordi; Spadaro, Salvatore; Junyent Giralt, Gabriel
    IEEE communications letters
    Date of publication: 2012-02
    Journal article

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  • Benefits of implementing a dynamic impairment-aware optical network: results of EU Project DICONET

     Angelou, Marianna; Azodolmolky, Siamak; Tomkos, Ioannis; Perello Muntan, Jordi; Spadaro, Salvatore; Careglio, Davide; Manousakis, Kostas; Kokkinos, Panagiotis; Varvarigos, Emmanouel A.; Staessens, Dimitri; Colle, Didier; Saradhi, Chava Vijaya; Gagnaire, Maurice; Ye, Yabin
    IEEE communications magazine
    Date of publication: 2012
    Journal article

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  • Cross-layer approaches for planning and operating impairment-aware optical networks

     Sole Pareta, Josep; Subramaniam, Suresh; Careglio, Davide; Spadaro, Salvatore
    Proceedings of the IEEE
    Date of publication: 2012-05
    Journal article

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  • Enhanced Optical Networks Featuring Adaptable and Highly Scalable Multi-granular Transport Services (ELASTIC) - TEC2011-27310

     Junyent Giralt, Gabriel; Spadaro, Salvatore; Comellas Colome, Jaume; Gené Bernaus, Joan M.; Velasco Esteban, Luis; Perello Muntan, Jordi; Conesa Fernandez, Josep; Agraz Bujan, Fernando; Ruiz Ramírez, Marc; Hernandez Sola, Guillem; Pages Cruz, Albert; Khodashenas, Pooria Saiyad
    Participation in a competitive project

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  • Enhanced optical networks featuring adaptable and highly scalable multi-granular transport services

     Ruiz Ramírez, Marc; Junyent Giralt, Gabriel; Comellas Colome, Jaume; Gené Bernaus, Joan M.; Conesa Fernandez, Josep; Velasco Esteban, Luis; Perello Muntan, Jordi; Agraz Bujan, Fernando; Hernandez Sola, Guillem; Pages Cruz, Albert; Khodashenas, Pooria Saiyad; Spadaro, Salvatore
    Participation in a competitive project

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  • ONDM 2012

     Pages Cruz, Albert; Perello Muntan, Jordi; Spadaro, Salvatore
    Award or recognition

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  • Lightpath fragmentation for efficient spectrum utilization in dynamic elastic optical networks

     Pages Cruz, Albert; Perello Muntan, Jordi; Spadaro, Salvatore
    International Conference on Optical Networking Design and Modeling
    Presentation's date: 2012-04-18
    Presentation of work at congresses

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  • Cross-layer optimization in Optical Networks  Open access

     Angelou, Marianna
    Defense's date: 2012-04-16
    Department of Computer Architecture, Universitat Politècnica de Catalunya
    Theses

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    Network planning and operation in core optical networks require processes that lead to a cost-effective network able to effectively accommodate the given traffic demands. Crosslayer techniques that exploit information coming from the transport plane to serve either the network planning or the operation phases have been proposed to achieve optimal resource utilization and network performance. Dynamic impairment-aware networking refers to a solution that utilizes the dynamicity as well as the valuable physical-layer information of a reconfigurable WDM network to provide a smooth transition from the quasi-static networking of today to an intelligent reconfigurable and physical impairment-aware architecture. The concept of physical layer awareness allows intelligent techniques to offer optimal planning, dynamic configuration and management of the network while ensuring strong quality of transmission (QoT). A physical-layer performance estimating tool called Q-tool, has been designed and developed to deliver fast and accurate QoT assessments in dynamic single line-rate WDM networks employing 10 Gb/s OOK systems. The Q-tool was developed so as to feed with QoT evaluations the various cross-layer modules including offline RWA, monitor placement, regenerator placement, online RWA and failure handling. The significance of the physical-layer awareness and the role of Q-tool in the online routing strategy have been experimentally investigated using an impairment-enabled control-plane testbed. A cross-layer module that utilizes physical layer information to optimize the planning phase of single line-rate networks has been also developed; a monitor placement scheme was designed that takes into account partial monitoring information coming from the physical layer to decide the optimum number and locations of the optical monitoring devices. A techno-economic analysis was also conducted to explore the cost implications stemming from the resource optimization of a dynamic single line-rate network. Impairment aware and impairment-unaware algorithms along with the developed QoT tool were used to compare the planning solutions in terms of CapEx and OpEx. The challenges arising in the core networks of the next generation have also been addressed. Flexible optical networking has been introduced by the research community as a way to offer efficient utilization of the available optical resources while offering ultra-high speed rates. As opposed to the rate-specific and fixed-grid solution of a mixed line-rate (MLR) network, flexible networks are bandwidth agnostic and have the ability to adapt on- demand the delivered bit-rate. Yet, the increased level of flexibility imposes complex requirements; during network operation traffic is changing with time, leaving windows of spectrum of variable size unused. Moreover, interference from the neighbouring channels has to be taken into account and sufficient guard-bands ought to be considered. In such context the physical layer requirements for a spectrum-flexible optical superchannel were experimentally investigated by implementing a set of networking scenarios. The importance of the result is that it can act as input for cognitive algorithms that will enable a novel networking paradigm. Finally next generation core networks were evaluated from a cost, spectral and energy perspective so as to give a comprehensive view of the potential of the proposed technologies. The resource optimization achieved by flexible networks has been compared to single and mixed line-rate networks under the prism of cost and energy efficiency. It was shown that the capability of flexible networks to allocate efficiently the available spectrum, counterbalances the additional capital expenditures that are required to migrate to a multi-carrier system. In addition flexible networks achieve low energy per bit as they use just the amount of network resources needed for the given input traffic.

  • Advanced Routing Mechanisms in ASON/GMPLS Networks  Open access

     Agraz Bujan, Fernando
    Defense's date: 2012-10-01
    Department of Signal Theory and Communications, Universitat Politècnica de Catalunya
    Theses

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    Current network infrastructures are supported on a layered model whereby heterogeneous data traffic can be seamlessly transported. In this architecture, where client/server relationships are established between adjacent layers, there exists an IP layer on top, two intermediate Asynchronous Transfer Mode (ATM) and Synchronous Digital Hierarchy (SDH) layers, and a Wavelength Division Multiplexing (WDM) layer at the bottom. Despite the benefits provided by the intermediate ATM and SDH layers (i.e., QoS and resilience), the complex interaction between them and the introduced overhead motivate an evolution towards a lighter model, where IP flows are directly sent through the WDM layer. In this new IP/WDM model the functionalities formerly provided by the ATM and SDH layers are moved to the optical domain. From an operational perspective, the static nature of current transport networks, which leads to long service provisioning times (i.e., hours or days), becomes incompatible with the dynamic patterns associated to the prevalent IP traffic. To overcome these limitations, the ITU-T proposed the Automatically Switched Optical Network (ASON) architecture, which utilizes a control plane to provide fast and reliable lightpaths within the optical transport network. In addition, the Generalized Multi-Protocol Label Switching (GMPLS) model defined by the IETF appears as the most promising technology to implement the functionalities of the ASON control plane. Although being a significant advance towards flexible and easy-to-maintain transport network architectures, the ASON/GMPLS paradigm still presents three major open issues that are addressed in this thesis. First, due to the coarse granularity offered by the WDM transport technology, established connections remain underused when sub-wavelength client flows must be transmitted. In light of this, a multi-layer approach, where different higher level data flows are aggregated in the IP layer and transmitted over the same optical path, appears as the most valid solution. Besides, the GMPLS technology is more than indicated to implement the control plane in this multi-layer architecture, since it allows the management of different switching technologies in an integrated way. In this regard, this thesis reports the experimental design and validation of a GMPLS-controlled multi-layer optical transport network. Second, even though pure optical transmission enabled by WDM provides high bandwidth in a cost-effective way, it is also very sensitive to the physical layer impairments that affect to the transmitted optical signal and, thus, to the transported data. Hence, a control plane capable of managing physical layer information to provide feasible lightpaths becomes a must. This thesis introduces and experimentally evaluates different architectural solutions to implement an impairment-aware GMPLS-based control plane. Finally, as transport network infrastructures grow, they are typically segmented into domains due to administrative, technological, or scalability reasons. Furthermore, the interconnection of network infrastructures managed by different operators is mandated by the need to provide long distance connectivity. Here, confidentiality and reliability concerns become of paramount importance. All this justifies the need for multi-domain networks. In GMPLS-controlled multi-domain optical transport networks, this partitioning affects to end-to-end service provisioning, which is hindered by the reduced information exchange between domains resulting from the fulfillment of segmentation criteria. As the third goal of this thesis, different mechanisms for scalable and effective end-to-end service provisioning are proposed in this multi-domain scenario.

    Les xarxes de comunicacions actuals segueixen un model distribuït de quatre capes que permet la transmissió de tràfic de dades heterogeni de forma eficaç sobre la mateixa infraestructura de transport. En aquesta arquitectura, la capa superior correspon a la capa IP, seguida per dues capes intermèdies que són la capa ATM (Asynchronous Transfer Mode) i la capa SDH (Synchronous Digital Hierarchy) i, finalment, la capa WDM (Wavelength Division Multiplexing). Encara que les capes ATM i SDH proporcionen beneficis com qualitat de servei i protecció i restauració, també comporten una sèrie de problemes com interaccions complexes entre elles i un excés d'informació de control. Això fa necessari evolucionar cap a una arquitectura més lleugera on els fluxos IP es puguin enviar directament a través de la capa WDM. En aquest nou model IP/WDM les funcionalitats proporcionades inicialment per les capes ATM i SDH es traspassen al domini òptic.Des d'un punt de vista operacional, la naturalesa estàtica del model en quatre capes fa que els temps de provisió de serveis siguin molt llargs (d'hores o dies) i, per tant, incompatibles amb els patrons de tràfic IP que són altament dinàmics. Per superar aquestes limitacions, la ITU-T va proposar l'arquitectura ASON (Automatically Switched Optical Network) que utilitza un pla de control per proporcionar connexions en la xarxa òptica de forma ràpida i fiable. A més, la tecnologia GMPLS (Generalized Multi-Protocol Label Switching), definida per la IETF, apareix com el model més prometedor per implementar les funcionalitats del pla de control d'ASON.Tot i que el paradigma ASON/GMPLS suposa un avenç significatiu per aconseguir un model flexible i fàcil de mantenir, encara presenta una sèrie de limitacions que es tracten en aquesta tesi.Primer, degut a la granularitat de longitud d'ona oferida per la tecnologia de transport WDM, els circuits òptics establerts queden infrautilitzats quan transmeten fluxos de dades de client de granularitat inferior. Per aquest motiu una solució multi-capa, en la que aquests fluxos de client puguin ser agregats a la capa IP i després transportats pel mateix circuit en la capa òptica, sembla la més apropiada. A més, la tecnologia GMPLS resulta molt adient per implementar el pla de control en aquesta arquitectura multi-capa, ja que permet la gestió de diferents tecnologies de commutació de forma integrada. En aquest context, aquesta tesi descriu el desenvolupament i validació experimental d'una xarxa de transport òptic multi-capa controlada per un pla de control GMPLS.En segon lloc, encara que la transmissió purament òptica basada en WDM proporciona un gran ample de banda amb un cost reduït, també és molt sensible als efectes negatius que afecten al senyal òptic transmès i, per tant, a la informació transportada. En aquest context esdevé necessari un pla de control que sigui capaç de manegar la informació associada a la capa òptica. Aquesta tesi presenta i avalua de forma experimental diferents solucions per implementar un pla de control GMPLS amb gestió dels impediments físics associats a la capa òptica.Finalment, degut al creixement de les infraestructures de xarxa, aquestes s'acostumen a particionar ja sigui per raons tecnològiques, administratives o d'escalabilitat. A més, la interconnexió entre dominis de diferents operadors, necessària per proporcionar connectivitat a llarga distància, implica problemes de confidencialitat entre operadors. Tot això dóna lloc a les xarxes multi-domini. En xarxes òptiques multi-domini controlades amb GMPLS, aquest particionat afecta a la provisió de serveis extrem a extrem, que es veu afectada pel limitat intercanvi d'informació causat per la necessitat de satisfer els requeriments esmentats. El tercer objectiu d'aquesta tesi consisteix en proporcionar mecanismes de provisió de connexions extrem a extrem, escalables i efectius, en aquest escenari multi-domini.

  • Planning of optical and IT resources for efficient virtual infrastructure embedding

     Pages Cruz, Albert; Perello Muntan, Jordi; Spadaro, Salvatore
    International Conference on Photonics in Switching
    Presentation's date: 2012-09-14
    Presentation of work at congresses

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    This work addresses the offline problem of efficiently planning network substrates joining geographically distributed IT resource locations over high-capacity optical resources. Given an already known set of virtual infrastructure demands to be embedded over the network substrate, we present an iterative optimization heuristic that appropriately embeds all virtual infrastructure demands in order to minimize both the physical substrate IT and optical resources needed to allocate them. For this purpose, the heuristic arranges the demands in descending order, based on the amount of resources they require. Then, it processes all demands, one after another, optimally embedding each one of them on the network substrate using Integer Linear Programming (ILP) techniques. The performance of the proposed heuristic is highlighted through illustrative results.

  • Optimal allocation of virtual optical networks for the future internet

     Pages Cruz, Albert; Perello Muntan, Jordi; Spadaro, Salvatore; Garcia Espin, Joan Antoni; Ferrer Riera, Jordi; Figuerola, Sergi
    International Conference on Optical Networking Design and Modeling
    Presentation's date: 2012-04-17
    Presentation of work at congresses

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  • Routing protocol enhancements for power state engineering of green network elements

     Verchere, Dominique; Spadaro, Salvatore; Le Sauze, Nicolas; Morea, Annalisa
    European Conference on Networks and Optical Communications
    Presentation's date: 2012-06-21
    Presentation of work at congresses

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    A routing protocol is enhanced to advertise the power state of node interfaces for wavelength switched optical networks to allow tuning the power consumption according to the data traffic demands. By engineering the different power states, GMPLS controlled nodes are configured to preserve the QoS of incoming traffic volumes such as reliability as well as the constraints of carrier grade networks, such as stability and operation costs. For variable incoming traffic reference models, more than half of the total power consumption required for an European optical networks without any power saving capabilities can be saved from powering the optoelectronic interfaces column.

  • Virtual network embedding in optical infrastructures

     Pages Cruz, Albert; Perello Muntan, Jordi; Spadaro, Salvatore
    International Conference on Transparent Optical Networks
    Presentation's date: 2012-07-04
    Presentation of work at congresses

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  • Access to the full text
    Service and resource differentiation in shared-path protection environments to maximize network operator's revenues  Open access

     Velasco Esteban, Luis; Ruiz Ramírez, Marc; Perello Muntan, Jordi; Spadaro, Salvatore; Comellas Colome, Jaume
    Journal of optical communications and networking
    Date of publication: 2011-02
    Journal article

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    Network operators are facing hard competition for opportunities in the telecommunications market, forcing network investments to be carefully evaluated before the decision-making process. A great part of core network operators’ revenues comes from the provisioned connectivity services. Taking this premise as our starting point, we first examine the provisioning of differentiated services in current shared-path protection (SPP) environments. This analysis reveals that current resource assignment policies are only able to provide a very poor grade of service to the supported best-effort traffic. Aiming to improve this performance, a novel resource partitioning scheme called diff-WS is proposed, which differentiates those wavelengths supporting each class of service in the network. As a major goal of this paper, the benefits of diff-WS over current resource assignment policies are assessed from an economic perspective. For this purpose, the network operator revenues maximization (NORMA) problem is presented to design the optical network such that the operator’s revenues are maximized. To solve NORMA, we derive statistical models to obtain, given a certain grade of service, the highest traffic intensity for each class of service and resource partitioning scheme. These models turn NORMA into a nonlinear problem, which is finally addressed as an iterative approach, solving an integer linear programming (ILP) subproblem at each iteration. The obtained numerical results on several network topologies illustrate that diff-WS maximizes resource utilization in the network and, thus, the network operator’s profit.

  • Enhanced domain disjoint backward recursive TE path computation for PCE-based multi-domain networks

     Hernandez Sola, Guillem; Perello Muntan, Jordi; Agraz Bujan, Fernando; Velasco Esteban, Luis; Spadaro, Salvatore; Junyent Giralt, Gabriel
    Photonic network communications
    Date of publication: 2011-04
    Journal article

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    The ability of computing optimal routes poses new challenges when extending it to larger multi-domain network scenarios, as the quality of these computed endto-end inter-domain routes depends on the selection of the domain sequence to be traversed. In the scope of the Internet Engineering Task Force (IETF), the Path Computation Element (PCE) Working Group has not provided definitive solutions to address the domain sequence selection problem, being still a work in progress. To this goal, the Path Computation Flooding (PCF) approach appears as a possible extension to Backward Recursive PCE-based Computation (BRPC) to calculate optimal end-to-end inter-domain paths without requiring a pre-configured domain sequence. Nonetheless, PCF presents major scalability issues in terms of network control overhead and path computation complexity, thus pleading for more accurate domain sequence selection techniques. This paper describes two novel mechanisms to establish inter-domain paths calculating the sequence of domains to be crossed when it is not known in advance. Both procedures make a good trade-off between the control overhead introduced and the accuracy of the computed end-to-end route. The obtained simulation results show the benefits of the proposed contributions, drastically reducing the control overhead while keeping the connection blocking probability close to the optimal values.

  • Experimental Demonstration of an Impairment Aware Network Planning and Operation Tool for Transparent/Translucent Optical Networks

     Azodolmolky, Siamak; Perello Muntan, Jordi; Angelou, Marianna; Agraz Bujan, Fernando; Velasco Esteban, Luis; Spadaro, Salvatore; Pointurier, Yvan; Francescon, Antonio; Saradhi, Chava Vijaya; Kokkinos, Panagiotis; Varvarigos, Emmanouel A.; Al Zahr, Sawsan; Gagnaire, Maurice; Gunkel, Mathias; Klonidis, Dimitrios; Tomkos, Ioannis
    Journal of lightwave technology
    Date of publication: 2011-02-15
    Journal article

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  • GMPLS control plane network design with resilience guarantees

     Ruiz Ramírez, Marc; Perello Muntan, Jordi; Velasco Esteban, Luis; Spadaro, Salvatore; Comellas Colome, Jaume; Junyent Giralt, Gabriel
    Journal of lightwave technology
    Date of publication: 2011-01-01
    Journal article

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    A one-to-one association between data and control channels has traditionally existed in transport networks. Being the control plane embedded in the data plane, the design of the former, as well as its resilience, has been addressed in the latter’s one. However, a main GMPLS architectural requirement is to provide a clean separation between control and data planes. In this sense, the control plane in GMPLS networks may describe a different topology than the data plane, even realized over a separated IP network. As a consequence of this, data and control network design become no more linked in such scenarios. To the best of our knowledge, no works in the literature have addressed an independent design of the control plane in GMPLS-enabled networks regardless of the data plane. In this paper, we provide a method to obtain the optimal GMPLS control plane design, minimizing the network Capital Expenditures (CAPEX) while matching specific resilience requirements. To this goal, the problem of finding an optimal control plane topology that ensures a certain resilience level is formulated as a non-linear combinatorial model. This model, however, does not scale properly for large backbone networks. In view of this, a constructive linear method is also presented and its optimality validated through simulations on several reference network scenarios. Furthermore, its benefits in terms of total execution time are also highlighted.

  • Future Internet testbeds/experimentation between BRazil and Europe - EU

     Junyent Giralt, Gabriel; Perello Muntan, Jordi; Spadaro, Salvatore
    Participation in a competitive project

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  • Experimental comparison of impairment-aware RWA algorithms in a GMPLS-controlled dynamic optical network

     Angelou, Marianna; Agraz Bujan, Fernando; Kokkinos, Panagiotis; Perello Muntan, Jordi; Azodolmolky, Siamak; Varvarigos, Emmanouel; Spadaro, Salvatore; Tomkos, Ioannis
    Future Network and MobileSummit
    Presentation's date: 2011-06-15
    Presentation of work at congresses

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  • Solutions for building service oriented optical networks

     Escalona Zorita, Eduard
    Defense's date: 2011-05-04
    Department of Signal Theory and Communications, Universitat Politècnica de Catalunya
    Theses

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  • Experimental evaluation of a full-meshed domain abstraction design model for reduced state information dissemination in multi-domain PCE-based WSONs

     Pagès, Albert; Casellas, Ramón; Perello Muntan, Jordi; Martinez, Ricardo; Spadaro, Salvatore; Muñoz González, Raul
    European Conference and Exposition on Optical Communications
    Presentation's date: 2011-09-21
    Presentation of work at congresses

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    A novel full-meshed domain abstraction model for scalable state information in PCEbased WSONs is presented. We experimentally evaluate the state information update reduction and the blocking improvement with regard to a shortest path model.

  • Scalable hybrid path computation procedure for PCE-based multi-domain WSON networks

     Hernandez Sola, Guillem; Perello Muntan, Jordi; Agraz Bujan, Fernando; Spadaro, Salvatore; Comellas Colome, Jaume; Junyent Giralt, Gabriel
    International Conference on Transparent Optical Networks
    Presentation's date: 2011
    Presentation of work at congresses

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    In the Hierarchical Path Computation Element (H-PCE) architecture, an optimum end-to-end path is computed using a hierarchical relationship among PCEs. An H-PCE-based path computation procedure provides low network blocking probability meanwhile it results on a great amount of control overhead messages. In this paper we propose a hybrid path computation procedure based on the H-PCE architecture and the Backward Recursive PCE-Based Computation (BRPC). Extensive simulation results show that the proposed approach performs better than H-PCE in terms of network control overhead.

  • A GMPLS/OBS network architecture enabling QoS-aware end-to-end burst transport

     Pedroso, Pedro; Perello Muntan, Jordi; Klinkowski, Miroslaw; Careglio, Davide; Spadaro, Salvatore; Sole Pareta, Josep
    International Conference on High Performance Switching and Routing
    Presentation of work at congresses

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    A novel monitor placement algorithm for accurate performance monitoring in optical networks  Open access

     Angelou, Marianna; Pointurier, Yvan; Azodolmolky, Siamak; Careglio, Davide; Spadaro, Salvatore; Tomkos, Ioannis
    Optical Fiber Communication Conference and Exposition
    Presentation's date: 2011
    Presentation of work at congresses

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    We propose a novel monitor placement algorithm that reduces significantly the number of monitors required to accurately assess the QoT of all lightpaths established in an optical network, compared to other monitor placement methods.

  • Dynamic Impairment-Aware Optical Networking: Some Experimental Results of the EU DICONET Project

     Spadaro, Salvatore; Perello Muntan, Jordi; Agraz Bujan, Fernando; Angelou, Marianna; Azodolmolky, Siamak; Qin, Yixuan; Nejabati, Reza; Simeonidou, Dimitra; Tomkos, Ioannis
    International Conference on Transparent Optical Networks
    Presentation's date: 2011-06-29
    Presentation of work at congresses

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  • Experimental evaluation of centralized failure restoration in a dynamic impairment-aware all-optical network

     Perello Muntan, Jordi; Spadaro, Salvatore; Agraz Bujan, Fernando; Angelou, Marianna; Azodolmolky, Siamak; Qin, Yixuan; Nejabati, Reza; Simeonidou, Dimitra; Kokkinos, Panagiotis; Varvarigos, Emmanouel A.; Al Zahr, Sawsan; Gagnaire, Maurice; Tomkos, Ioannis
    Optical Fiber Communication Conference and Exposition
    Presentation's date: 2011-03-08
    Presentation of work at congresses

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  • Experimental demonstration of an enhanced impairment-aware path computation element

     Spadaro, Salvatore; Perello Muntan, Jordi; Agraz Bujan, Fernando; Azodolmolky, Siamak; Angelou, Marianna; Qin, Yixuan; Nejabati, Reza; Simeonidou, Dimitra; Kokkinos, Pannagiotis; Varvarigos, Emmanouel; Ye, Yabin; Tomkos, Ioannis
    Optical Fiber Communication Conference and Exposition
    Presentation's date: 2011-03-08
    Presentation of work at congresses

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  • Power management of optoelectronic interfaces for dynamic optical networks

     Morea, Annalisa; Spadaro, Salvatore; Rival, Olivier; Perello Muntan, Jordi; Agraz Bujan, Fernando; Verchere, Dominique
    European Conference and Exposition on Optical Communications
    Presentation's date: 2011-09-21
    Presentation of work at congresses

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  • Scalable hybrid path computation procedure for PCE-based

     Hernandez Sola, Guillem; Perello Muntan, Jordi; Agraz Bujan, Fernando; Spadaro, Salvatore; Comellas Colome, Jaume; Junyent Giralt, Gabriel
    International Conference on Transparent Optical Networks
    Presentation's date: 2011-06-27
    Presentation of work at congresses

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  • A feedback-based hybrid OBS/OCS architecture with fast-over-slow capability

     Khodashenas, Pooria Saiyad; Perello Muntan, Jordi; Spadaro, Salvatore; Comellas Colome, Jaume; Junyent Giralt, Gabriel
    International Conference on Optical Network Design and Modeling
    Presentation's date: 2011-02-08
    Presentation of work at congresses

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  • GMPLS-based multidomain restoration: analysis, strategies, policies and experimental assessment

     Velasco Esteban, Luis; Agraz Bujan, Fernando; Martínez, Ricardo; Casellas, Ramón; Spadaro, Salvatore; Muñoz González, Raul; Junyent Giralt, Gabriel
    Journal of optical communications and networking
    Date of publication: 2010-07-01
    Journal article

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    A connection spanning, for example, several countries crosses multiple optical backbone networks, each one controlled by different administrators or operators. In this context, the interworking of these networks is thus necessary to set up end-to-end optical connections. A key issue when delivering such optical services is the use of efficient and fast restoration strategies to recover a connection disruption. To this end, there are several issues and policies that a network operator should address, such as interdomain failure information exchange and the point of repair (PoR) placement problem. Upon a failure’s occurrence, exchanging interdomain failure information results is essential to attain both an efficient use of the network resources (i.e., wavelength channels) and a fast restoration time. In this regard, within the GMPLS (Generalized Multi-Protocol Label Switching) framework, interdomain information exchange remains unstandardized. Three network operator policies are proposed to yield different restoration mechanisms according to different interdomain failure exchanges. Additionally, three PoR strategies are pointed out and are qualitatively compared. Finally, selected policies and restoration strategies are experimentally validated and compared in terms of the restoration time. Experiments have been carried out over a multidomain optical network infrastructure connecting the GMPLS-based control planes of the UPC CARISMA and the CTTC ADRENALINE test beds.

  • Scalable path computation flooding approach for PCE-based multi-domain networks

     Perello Muntan, Jordi; Hernandez Sola, Guillem; Agraz Bujan, Fernando; Spadaro, Salvatore; Comellas Colome, Jaume
    ETRI journal
    Date of publication: 2010-08
    Journal article

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  • Using updated neighbor state information for efficient contention avoidance in OBS networks

     Perello Muntan, Jordi; Agraz Bujan, Fernando; Spadaro, Salvatore; Comellas Colome, Jaume; Junyent Giralt, Gabriel
    Computer communications
    Date of publication: 2010-01
    Journal article

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  • Deployment and validation of GMPLS-controlled multi-layer integrated routing over the ASON/GMPLS CARISMA test-bed

     Agraz Bujan, Fernando; Velasco Esteban, Luis; Perello Muntan, Jordi; Ruiz Ramírez, Marc; Spadaro, Salvatore; Junyent Giralt, Gabriel; Comellas Colome, Jaume
    Journal of networks
    Date of publication: 2010-11
    Journal article

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    A GMPLS/OBS network architecture enabling QoS-aware end-to-end burst transport  Open access

     Pedroso, Pedro; Klinkowski, Miroslaw; Perello Muntan, Jordi; Spadaro, Salvatore; Careglio, Davide; Sole Pareta, Josep
    Date: 2010-07-01
    Report

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    This paper introduces a Generalized Multi-Protocol Label Switching (GMPLS)-enabled Optical Burst Switched (OBS) network architecture featuring end-to-end QoS-aware burst transport services. This is achieved by setting up burst Label Switched Paths (LSPs) properly dimensioned to match specific burst drop probability requirements. These burst LSPs are used for specific guaranteed QoS levels, whereas the remaining network capacity can be left for best-effort burst support. Aiming to ensure the requested burst drop probability figures even under bursty traffic patterns, burst LSPs’ performance is continuously monitored. Therefore, GMPLS-driven capacity reconfigurations can be dynamically triggered whether unfavorable network conditions are detected. Through the paper, the GMPLS/OBS architecture is firstly detailed, followed by the presentation of the optimized methods used for the initial burst LSP dimensioning. The successful network performance is finally illustrated by simulations on several network scenarios.

  • Scalable, Tunable and Resilient Optical Networks Guaranteeing Extremely-high Speed Transport

     Spadaro, Salvatore; Sole Pareta, Josep; Perello Muntan, Jordi; Careglio, Davide; Velasco Esteban, Luis; Junyent Giralt, Gabriel; Comellas Colome, Jaume
    Participation in a competitive project

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  • Experimental UpdateLess Evolutive Routing

     Perello Muntan, Jordi; Spadaro, Salvatore; Sole Pareta, Josep; Cabellos Aparicio, Alberto; Careglio, Davide
    Participation in a competitive project

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