Now showing items 21-40 of 68

  • Experimental evaluation of a dynamic PCE-based regenerator-efficient IA-RWA algorithm in translucent WSON 

    Castro Casales, Alberto; Martínez, Ricardo; Velasco Esteban, Luis Domingo; Casellas Regi, Ramón; Muñoz González, Raul; Comellas Colomé, Jaume (2012)
    Conference report
    Open Access
    We devise a novel dynamic PCE-based impairment-aware RWA algorithm in translucent GMPLS WSON that minimizes regenerator usage. Experimental evaluation carried out on the Open GMPLS/PCE control plane of CTTC ADRENALINE ...
  • Extending the flexgrid optical core towards the edges 

    Velasco Esteban, Luis Domingo; Ruiz Ramírez, Marc; Castro Casales, Alberto; Comellas Colomé, Jaume (Institute of Electrical and Electronics Engineers (IEEE), 2013)
    Conference report
    Restricted access - publisher's policy
    National IP/MPLS network have being designed on top of fixed-grid DWDM optical networks so to spread out covering large areas. Besides, multilayer IP/MPLS-over-DWDM networks take advantage from grooming to achieve high ...
  • Global concurrent optimization: advantages and opportunities in flexgrid-based networks 

    Castro Casales, Alberto; Velasco Esteban, Luis Domingo; Comellas Colomé, Jaume; Junyent Giralt, Gabriel (Institute of Electrical and Electronics Engineers (IEEE), 2013)
    Conference report
    Restricted access - publisher's policy
    In future flexgrid core networks the amount of lightpaths might increase significantly as a consequence of the finer granularity in the use of the optical spectrum. Different spectrum bandwidth can be allocated to each ...
  • GMPLS control plane network design with resilience guarantees 

    Ruiz Ramírez, Marc; Perelló Muntan, Jordi; Velasco Esteban, Luis Domingo; Spadaro, Salvatore; Comellas Colomé, Jaume; Junyent Giralt, Gabriel (2011-01-01)
    Article
    Restricted access - publisher's policy
    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 ...
  • High capacity optical networks based on space division multiplexing 

    Behnam Shariati, Mohammad; Comellas Colomé, Jaume; Klonidis, Dimitrios; Velasco Esteban, Luis Domingo; Tomkos, Ioannis (John Wiley & sons, 2017-09-01)
    Part of book or chapter of book
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    This book discusses Elastic Optical Networks (EONs) from an operational perspective. It presents algorithms that are suitable for real-time operation and includes experimental results to further demonstrate the feasibility ...
  • Impact of aggregation level on the performance of dynamic lightpath adaptation under time-varying traffic 

    Asensio Carmona, Adrian; Klinkowski, Miroslaw; Ruiz Ramírez, Marc; Lopez, Victor Bohorquez; Castro Casales, Alberto; Velasco Esteban, Luis Domingo; Comellas Colomé, Jaume (Institute of Electrical and Electronics Engineers (IEEE), 2013)
    Conference report
    Restricted access - publisher's policy
    In this article we focus on lightpath adaptation under time-varying traffic in a dynamic elastic optical network (EON) implementing flexgrid optical technology. In the considered scenario, a number of IP/MPLS metro area ...
  • Impact of filter sharpness on the performance of elastic optical networks 

    Sayyad Kodashenas, Pouria; Rivas Moscoso, José Manuel; Klonidis, Dimitrios; Tomkos, Ioannis; Behnam Shariati, Mohammad; Comellas Colomé, Jaume (Institute of Electrical and Electronics Engineers (IEEE), 2015)
    Conference report
    Restricted access - publisher's policy
    Elastic optical network (EON) technology arises as a promising solution for future high-speed optical transport networks, inasmuch as it can provide superior flexibility and scalability in the spectrum allocation for ...
  • Impact of optical hop constraints on the IP/MPLS-over-WSON Networks CAPEX 

    Liu, Fengqing; Comellas Colomé, Jaume (2015-11-01)
    Article
    Open Access
    In this work, the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops, the cost of networks ...
  • Improving link spectrum utilization in Flexgrid optical networks 

    Comellas Colomé, Jaume; Junyent Giralt, Gabriel (Institute of Electrical and Electronics Engineers (IEEE), 2015-07-01)
    Article
    Open Access
    Flexible grid optical networks are emerging as an appealing solution for future high-speed optical transport because they can provide superior flexibility and scalability and cope with the rapid growth of Internet traffic. ...
  • Learning from the optical spectrum: failure detection and identification [Invited] 

    Behnam Shariati, Mohammad; Ruiz Ramírez, Marc; Comellas Colomé, Jaume; Velasco Esteban, Luis Domingo (Institute of Electrical and Electronics Engineers (IEEE), 2018-07-23)
    Article
    Open Access
    The availability of coarse-resolution cost-effective Optical Spectrum Analyzers (OSA) allows its widespread deployment in operators’ networks. In this paper, we explore several machine learning approaches for soft-failure ...
  • Learning from the optical spectrum: soft-failure identification and localization 

    Velasco Esteban, Luis Domingo; Behnam Shariati, Mohammad; Vela, Alba P.; Comellas Colomé, Jaume; Ruiz Calvo, Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2018)
    Conference report
    Restricted access - publisher's policy
    The availability of coarse-resolution cost-effective Optical Spectrum Analyzers (OSA) allows its widespread deployment in operators' networks. In this paper, several machine learning approaches for failure identification ...
  • Minimum channel spacing in an ofdm cpfsk optical coherent system 

    Prat Gomà, Josep Joan; Comellas Colomé, Jaume; Junyent Giralt, Gabriel (1998-03)
    Article
    Restricted access - publisher's policy
    Channel spacing in optical frequency-division multiplexed (OFDM) coherent optical systems with continuous-phase frequency-shift-keying (CPFSK) is obtained both theoretically and experimentally. The bit error ratio is derived ...
  • Modeling the routing and spectrum allocation problem for flexgrid optical networks 

    Velasco Esteban, Luis Domingo; Klinkowski, Miroslaw; Ruiz Ramírez, Marc; Comellas Colomé, Jaume (2012-12)
    Article
    Restricted access - publisher's policy
    Flexgrid optical networks are attracting huge interest due to their higher spectrum efficiency and flexibility in comparison with traditional wavelength switched optical networks based on the wavelength division multiplexing ...
  • Modified duobinary polarization-shift keying transmission scheme 

    Gené Bernaus, Joan M.; Soler Rocasalbas, Marçal; Contreras Leyva, Miguel A.; Comellas Colomé, Jaume; Prat Gomà, Josep Joan (2003)
    Conference lecture
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    A new version of duobinary polarization-shift keying scheme is proposed. The relocation of the duobinary filter at the receiver side and the optimization of both transmitter and receiver electrical filters offer a receiver ...
  • Motivations and outcomes: a study of an intensive international course 

    Myrup Pedersen, Jens; Gutiérrez López, José Manuel; Kirikova, Marite; Zabludowski, Lukasz; Comellas Colomé, Jaume (Tempus Publications, 2017-05-10)
    Article
    Restricted access - publisher's policy
    In this paper, we study what motivates students and university teachers to do intensive international courses, and how they evaluate the outcomes. The study is based on three years of an Erasmus funded Intensive Programme ...
  • NORMA: Network Operator Revenues Maximization 

    Velasco Esteban, Luis Domingo; Ruiz Ramírez, Marc; Comellas Colomé, Jaume; Junyent Giralt, Gabriel (IEEE, 2012)
    Conference report
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    A great part of core network operators’ gross profit comes from the provisioned connectivity services. In this work, we analyze the provisioning of differentiated services in current Shared Path Protection (SPP) environments. ...
  • On the benefits of FMF based data center interconnection utilizing MIMO-less PAM-M transceivers 

    Behnam Shariati, Mohammad; Diamantopoulos, Nikolaos-Panteleimon; Klonidis, Dimitrios; Comellas Colomé, Jaume; Tomkos, Ioannis (Institute of Electrical and Electronics Engineers (IEEE), 2017)
    Conference lecture
    Restricted access - publisher's policy
    Space division multiplexing (SDM) has been proposed to cost-effectively increase the capacity of optical transmission systems. The cost savings can be realized by introducing some levels of spatial integration of elements. ...
  • On the benefits of multi-path recovery in flexgrid optical networks 

    Castro Casales, Alberto; Velasco Esteban, Luis Domingo; Comellas Colomé, Jaume; Junyent Giralt, Gabriel (2014-12-01)
    Article
    Restricted access - publisher's policy
    We propose a new recovery scheme, called multi-path recovery (MPR), specifically designed for flexgrid-based optical networks. It combines protection and restoration schemes to jointly recover, in part or totally, the ...
  • On the performance of dynamic source aggregation of sub-wavelength connections in EONs 

    Sayyad Khodashenas, Pouria; Comellas Colomé, Jaume; Perelló Muntan, Jordi; Spadaro, Salvatore; Junyent Giralt, Gabriel (Institute of Electrical and Electronics Engineers (IEEE), 2014)
    Conference report
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    In elastic optical networks, heterogeneous traffic demands are typically supported by a single type of bandwidth-variable transmitters, which is not always spectrum and cost efficient. In light of this, we recently proposed ...
  • On the performance of flexgrid-based optical networks 

    Velasco Esteban, Luis Domingo; Ruiz Ramírez, Marc; Pedrola Escribà, Òscar; Castro Casales, Alberto; Klinkowski, Miroslaw; Careglio, Davide; Comellas Colomé, Jaume (Institute of Electrical and Electronics Engineers (IEEE), 2012)
    Conference report
    Restricted access - publisher's policy
    The ever increasing IP traffic volume has finally brought to light the high inefficiency of current wavelength-routed rigid-grid networks in matching the client layer requirements. Such an issue results in the deployment ...