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    Multi-domain optical routing: Is there life beyond extending BGP?  Open access

     Marín Tordera, Eva; Masip Bruin, Javier; Yannuzzi, Marcelo; Serral Gracia, Rene
    Optical switching and networking
    Date of publication: 2014-01-01
    Journal article

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    The design of new inter-domain optical routing protocols may start from scratch, or on the contrary exploits all the research already developed in IP networks with the Border Gateway Protocol (BGP). Even though the network premises under which BGP was conceived have drastically changed, the pervasive deployment of BGP makes almost impossible its replacement, hence everything indicates that BGP-based routing will remain present in the coming years. In light of this, the approach often used for distributing reachability information and routing inter-domain connections below the IP layer has been to propose extensions to the BGP protocol, what unfortunately exports all well-known BGP weaknesses to these routing scenarios. In this paper we deeply analyze all these problems in order the reader to get a clear idea of the existing limitations inherent to the BGP, before exploring the routing problem in optical networks. Then, focusing on the optical layer we will demonstrate that current optical extensions of BGP do not meet the particular optical layer constraints. We then propose minor, though effective, changes to a path vector protocol overall offering a promising line of work and a simple solution designed to be deployed on a multi-domain and multi-layer scenario. (C) 2013 Elsevier B.V. All rights reserved.

    The design of new inter-domain optical routing protocols may start from scratch, or on the contrary exploits all the research already developed in IP networks with the Border Gateway Protocol (BGP). Even though the network premises under which BGP was conceived have drastically changed, the pervasive deployment of BGP makes almost impossible its replacement, hence everything indicates that BGP-based routing will remain present in the coming years. In light of this, the approach often used for distributing reachability information and routing inter-domain connections below the IP layer has been to propose extensions to the BGP protocol, what unfortunately exports all well-known BGP weaknesses to these routing scenarios. In this paper we deeply analyze all these problems in order the reader to get a clear idea of the existing limitations inherent to the BGP, before exploring the routing problem in optical networks. Then, focusing on the optical layer we will demonstrate that current optical extensions of BGP do not meet the particular optical layer constraints. We then propose minor, though effective, changes to a path vector protocol overall offering a promising line of work and a simple solution designed to be deployed on a multi-domain and multi-layer scenario. (C) 2013 Elsevier B.V. All rights reserved.

  • A survey and taxonomy of ID/Locator Split Architectures

     Ramirez Almonte, Wilson; Masip Bruin, Javier; Yannuzzi, Marcelo; Serral Gracia, Rene; Martinez Manzanilla, Anny Gabriela; Siddiqui, Muhammad Shuaib
    Computer networks
    Date of publication: 2014-02-26
    Journal article

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    The IP-based addressing scheme currently supporting the whole routing architecture embeds some well-known limitations that may significantly hinder the deployment of new applications and services on the Internet. Indeed, it is widely accepted that the unstoppable growth of Internet users is producing two well-known problems: (1) depletion of addresses, motivated by a design limitation of the currently deployed addressing scheme, and (2) the semantic overload of addresses. The main negative consequences of these problems may be summarized as: (i) exacerbating the geometrical growth of the routing tables, and (ii) affecting other network features, such as traffic engineering and mobility, in terms of resilience and disruption tolerant communications.; The relevant consequences that addressing brings to the overall network operation is pushing the networking community to study and propose new addressing architectures that may limit or even remove the negative effects (affecting network performance) stemmed from the currently deployed addressing architecture. To this end, researchers working on this area must have a perfect understanding of the weaknesses and limitations coming up from the nowadays architecture as well as a comprehensive knowledge of the alternatives proposed so far along with the most appealing research trends. Aligned to this scenario, this paper comes up with the aim of assisting the reader to both: (i) get insights about the most prominent limitations of the currently deployed addressing architecture, and (ii) survey the existing proposals based on ID/Locator Split Architectures (ILSAs) including an analysis of pros and cons, as well as a taxonomy aiming at formulating a design space for evaluating and designing existing and future ILSAs. (C) 2013 Elsevier B.V. All rights reserved.

    The IP-based addressing scheme currently supporting the whole routing architecture embeds some well-known limitations that may significantly hinder the deployment of new applications and services on the Internet. Indeed, it is widely accepted that the unstoppable growth of Internet users is producing two well-known problems: (1) depletion of addresses, motivated by a design limitation of the currently deployed addressing scheme, and (2) the semantic overload of addresses. The main negative consequences of these problems may be summarized as: (i) exacerbating the geometrical growth of the routing tables, and (ii) affecting other network features, such as traffic engineering and mobility, in terms of resilience and disruption tolerant communications.; The relevant consequences that addressing brings to the overall network operation is pushing the networking community to study and propose new addressing architectures that may limit or even remove the negative effects (affecting network performance) stemmed from the currently deployed addressing architecture. To this end, researchers working on this area must have a perfect understanding of the weaknesses and limitations coming up from the nowadays architecture as well as a comprehensive knowledge of the alternatives proposed so far along with the most appealing research trends. Aligned to this scenario, this paper comes up with the aim of assisting the reader to both: (i) get insights about the most prominent limitations of the currently deployed addressing architecture, and (ii) survey the existing proposals based on ID/Locator Split Architectures (ILSAs) including an analysis of pros and cons, as well as a taxonomy aiming at formulating a design space for evaluating and designing existing and future ILSAs. (C) 2013 Elsevier B.V. All rights reserved.

  • TEFIS: a single access point for conducting multifaceted experiments on heterogeneous test facilities

     Yannuzzi, Marcelo; Siddiqui, Muhammad Shuaib; Sällström, Annika; Pickering, B.; Serral Gracia, Rene; Martinez Manzanilla, Anny Gabriela; Chen, W.; Taylor, S.; Benbadis, F.; Leguay, J.; Borrelli, E.; Ormaetxea, I.; Campowsky, K.; Giammatteo, G.; Aristomenopoulos, G.; Papavassiliou, Symeon; Kuczynski, T.; Zielinski, S.; Seigneur, J.M.; Ballester Lafuente, C.; Johansson, J.; Masip Bruin, Javier; Caria, M.; Ribeiro Junior, J.R.; Salageanu, E.; Latanicki, J.
    Computer networks
    Date of publication: 2014-04-22
    Journal article

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    A few years ago, an experimental facility composed of networking gear and simulation tools was sufficient for testing the main features of a prototype before the final product could be launched to the Internet market. This paradigm has certainly changed, but the lack of platforms enabling the realistic assessment of the different facets of a product, including cross-cutting trials across different testbeds, poses strong limitations for researchers and developers. In light of this, we present an open platform that offers a versatile combination of heterogeneous experimental facilities called ¿TEstbed for Future Internet Services¿ (TEFIS). TEFIS provides a single access point for conducting cutting-edge experiments on testbeds that supply different capabilities, including testbeds dedicated to network performance, software performance, grid computing, and living labs. We shall show that TEFIS covers the entire life-cycle of a multifaceted experiment, with the advantage that a single testrun can seamlessly execute across different experimental facilities. In order to demonstrate the potential and versatility of the TEFIS platform, we describe the deployment of four distinct experiments and provide a set of results highlighting the benefits of using TEFIS. The experiments described in this article cover: (i) the experimentation with an open API called OPENER (which is an open and programmable environment for managing experimentation with SDN applications); (ii) an application for skiers and tourists at the Megève ski resort in France; (iii) an application that can dynamically adapt the Quality of Experience (QoE) of multimedia services for mobile users; and (iv) an augmented reality workspace for remote education and learning purposes based on videoconferencing.

    A few years ago, an experimental facility composed of networking gear and simulation tools was sufficient for testing the main features of a prototype before the final product could be launched to the Internet market. This paradigm has certainly changed, but the lack of platforms enabling the realistic assessment of the different facets of a product, including cross-cutting trials across different testbeds, poses strong limitations for researchers and developers. In light of this, we present an open platform that offers a versatile combination of heterogeneous experimental facilities called “TEstbed for Future Internet Services” (TEFIS). TEFIS provides a single access point for conducting cutting-edge experiments on testbeds that supply different capabilities, including testbeds dedicated to network performance, software performance, grid computing, and living labs. We shall show that TEFIS covers the entire life-cycle of a multifaceted experiment, with the advantage that a single testrun can seamlessly execute across different experimental facilities. In order to demonstrate the potential and versatility of the TEFIS platform, we describe the deployment of four distinct experiments and provide a set of results highlighting the benefits of using TEFIS. The experiments described in this article cover: (i) the experimentation with an open API called OPENER (which is an open and programmable environment for managing experimentation with SDN applications); (ii) an application for skiers and tourists at the Megève ski resort in France; (iii) an application that can dynamically adapt the Quality of Experience (QoE) of multimedia services for mobile users; and (iv) an augmented reality workspace for remote education and learning purposes based on videoconferencing.

  • Metrics and QoE assessment in P2PTV applications

     Serral Gracia, Rene; Yannuzzi, Marcelo; Marín Tordera, Eva; Martinez Manzanilla, Anny Gabriela; Masip Bruin, Javier
    International journal of internet protocol technology
    Date of publication: 2013
    Journal article

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    Peer-to-peer (P2P) is a growing technology offering an affordable platform to deploy distributed services and streaming of multimedia content through peer-to-peer television (P2PTV). Nevertheless, to promote such technology it is necessary to provide a solid streaming quality assessment mechanism. In this context, legacy solutions tied to service level agreements are no longer suitable, as for P2P systems, the service consumers become an active part by assisting in the service delivery. To overcome this limitation, we present a generic multi-layer monitoring and management framework to assess the quality of service (QoS) and the quality of experience (QoE) of multimedia traffic in any P2PTV streaming application. We also demonstrate the usefulness of our solution, by analysing the performance of a real streaming application in a P2PTV environment.

  • SECURity at the network EDge

     Yannuzzi, Marcelo
    Participation in a competitive project

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  • EQR: a new energy-aware query-based routing protocol for wireless sensor networks

     Ahvar, Ehsan; Serral Gracia, Rene; Marín Tordera, Eva; Masip Bruin, Javier; Yannuzzi, Marcelo
    Lecture notes in computer science
    Date of publication: 2012
    Journal article

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    Over the last years, a number of query-based routing protocols have been proposed for Wireless Sensor Networks (WSNs). In this context, routing protocols can be classified into two categories, energy savers and energy balancers. In a nutshell, energy saving protocols aim at decreasing the overall energy consumed by a WSN, whereas energy balancing protocols attempt to efficiently distribute the consumption of energy throughout the network. In general terms, energy saving protocols are not necessarily good at balancing energy and vice versa. In this paper, we introduce an Energy-aware Query-based Routing protocol for WSNs (EQR), which offers a good trade-off between the traditional energy balancing and energy saving objectives. This is achieved by means of learning automata along with zonal broadcasting so as to decrease the total energy consumption. We consider that, in the near future, EQR could be positioned as the routing protocol of choice for a number of query-based WSN applications, especially for deployments where the sensors show moderate mobility.

  • 17th European Conference on Networks and Optical Communications; 7th Conference on Optical Cabling and Infrastruct.

     Martinez Manzanilla, Anny Gabriela; Ramirez Almonte, Wilson; Yannuzzi, Marcelo; Serral Gracia, Rene; Marín Tordera, Eva; Sanchez Lopez, Sergio; Masip Bruin, Javier
    Participation in a competitive project

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  • Multi-Layer quality assessment framework for P2PTV applications

     Serral Gracia, Rene; Martinez Manzanilla, Anny Gabriela; Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier
    IEEE International Conference on Communications
    Presentation of work at congresses

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    The success of Peer-to-Peer (P2P) overlay networks has led to its broad adoption on different scenarios, thereby increasing the set of features present on such protocols, e. g., audio and video-conferencing, streaming of multimedia content using Peer-to-Peer TeleVision (P2PTV), and so on. The wide acceptance of P2P multimedia streaming by the end-users has captured the attention of content providers, making it a suitable candidate to be adopted as technology for the offered multimedia services. Nevertheless, to deliver a proper service, content providers, need to quantify and assess the quality perceived by the users. In the past, this assessment was embedded into Service Level Agreements under the client/server paradigm, but with the introduction of P2P, these solutions became unsuitable. To overcome this limitation, we present a Monitoring and Management Framework to assess the Quality of Service and the Quality of Experience of multimedia traffic in any P2PTV streaming application.

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    Coordinated Computation of Multi-layer Paths via Inter-layer PCE Communication: Standards, Interoperability and Deployment  Open access

     Chamania, Mohit; González De Dios, Oscar; López, Víctor; Cuaresma, Marta; Drogon, Marek; Jukan, Admela; Masip Bruin, Javier; Yannuzzi, Marcelo
    IEEE International Conference on Communications
    Presentation's date: 2012-06-15
    Presentation of work at congresses

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    The Path Computation Element (PCE) is positioned nowadays as one of the solutions that almost every carrier will eventually deploy. The PCE architecture as well as a number of components, including the PCE Communication Protocol (PCEP), have been standardized by the IETF. However, a number of challenges remain to be solved on its way from standards to deployment. In particular, the existing proposals for multilayer path computation within the PCE framework need to be further developed and tested, before considering their possible integration into operational networks. This is especially true for the interoperability of the various PCE implementations and the extensions such as the Virtual Network Topology Manager (VNTM) which cannot be taken for granted. This paper presents a functional implementation of coordinated computation of multilayer paths supported through inter-layer PCE communication, where one PCE is developed by industry and the other as an open-source effort. To this end, we consider an IP/MPLS network deployed over a Wavelength Switched Optical Network (WSON), each of which deploying its own PCE, in an attempt to create an inter-operable multilayer solution. We discuss the key challenges that the research community will face in this area, which in turn will drive a considerable part of the upcoming efforts in terms of standardization

  • FRA: A new fuzzy-based routing approach for optical transport networks

     Ahvar, Ehsan; Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier; Ahvar, S.
    European Conference on Networks and Optical Communications
    Presentation's date: 2012
    Presentation of work at congresses

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    Providing networks with QoS guarantees is one of the key issues to support current and future expected clients' demands. In this scenario, QoS routing is definitely critical as being responsible for defining those optimal routes supporting traffic forwarding throughout the whole network. This paper proposes two new QoS-aware RWA algorithms dealing with the routing inaccuracy problem, aiming at reducing blocking probability while limiting signaling overhead and balancing network load. The proposed algorithms extend the work already published by the authors on prediction based routing by adding a novel fuzzy-based technique featuring a powerful tool for modeling uncertainty. The proposed algorithms are compared with a well-known RWA algorithm and results show the benefit of introducing the fuzzy techniques in the RWA selection.

  • TEstbed for Future Internet Services

     Masip Bruin, Javier; Marín Tordera, Eva; Serral Gracia, Rene; Yannuzzi, Marcelo
    Participation in a competitive project

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    An Approach to a Fault Tolerance LISP Architecture  Open access

     Martinez Manzanilla, Anny Gabriela; Ramírez, Wilson; German Duarte, Martin; Serral Gracia, Rene; Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier
    International Conference on Wired/Wireless Internet Communications
    Presentation's date: 2011-06
    Presentation of work at congresses

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    Next Generation Internet points out the challenge of addressing "things" on both a network with (wired) and without (wireless) infrastructure. In this scenario, new efficient and scalable addressing and routing schemes must be sought, since currently proposed solutions can hardly manage current scalability issues on the current global Internet routing table due to for example multihoming practices. One of the most relevant proposals for an addressing scheme is the Locator Identifier Separation Protocol (LISP) that focuses its key advantage on the fact that it does not follow a disruptive approach. Nevertheless, LISP has some drawbacks especially in terms of reachability in the border routers. In face of this, in this paper we propose a protocol so-called LISP Redundancy Protocol (LRP), which provides an interesting approach for managing the reachability and reliability issues common on a LISP architecture, such as those motivated by an inter-domain link failure.

  • Modeling physical-layer impairments in multi-domain optical networks

     Yannuzzi, Marcelo; Marín Tordera, Eva; Serral Gracia, Rene; Masip Bruin, Javier; Gonzalez de Dios, Oscar; Jimenez Chico, Javier; Verchere, Dominique
    International Conference on Optical Networking Design and Modeling
    Presentation's date: 2011-02-08
    Presentation of work at congresses

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    The advantages of optical transparency are still confined to the boundaries of a domain, since the optical signals are subject to O/E/O conversions at the border nodes that separate two optical domains. The extension of transparent connections across domains requires advances both in the modeling of the impairments suffered by the optical signals as well as in devising strategies to exploit such models in practice. In this latter regard, one of the main challenges is to design information exchange models and protocols enabling optical bypass without disclosing detailed physical-layer information among domains. In this paper, we focus on the modeling and the exchange of impairmentrelated information between optical domains. We propose a model that conveniently captures the degradation experienced by an optical signal along a lightpath, and describe it use in the frontier between two neighbor domains. Our approach respects the privacy and administrative limits of carrier networks, while enabling the provision of transparent connections beyond domain boundaries. The model and strategies proposed in this paper generalize the contributions made by some of the most relevant works in the field, providing in this way a first attempt toward a unifying view and theory for quantifying the transmission impairments in DWDM optical networks.

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  • Bridging the Interoperability Gap Between the Internet and Optical Network Management Systems

     Yannuzzi, Marcelo; Masip Bruin, Javier; González de Dios, Óscar; García Argos, Carlos; Maciejewski, Maciej; Altmann, Jorn
    European Conference on Networks and Optical Communications
    Presentation's date: 2011-07
    Presentation of work at congresses

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    Despite the efforts made towards the convergence of packet and circuit switched technologies, the isolation between the Internet and the optical Network Management Systems (NMSs) remains unsolved. Today, carriers have nothing but manual means to coordinate the provisioning between the routers and L1 switches, and much less to communicate and coordinate policy rules, or failures between the IP networks and Ethernet/optical networks. In this paper, we outline the strengths of an easy-to-deploy solution, which can overcome the current separation between the IP and the optical NMSs. The solution consists of an adapter(a middle-box), especially designed to provide a simple, reliable, and automated communication channel between the two management layers. The adapter that we conceive will enable automated interoperability between the IP and the optical NMSs, in support of coordinated actions such as: i) IP service provisioning; ii) IP/MPLS offloading; and iii) coordinated self-healing. We contend that our approach not only eliminates the need for large scale integration into a single multi-layer management system, but also bridges the communication gap between two management ecosystems that are currently isolated.

  • An efficient and lightweight method for Service Level Agreement assessment

     Serral Gracia, Rene; Yannuzzi, Marcelo; Labit, Yann; Owezarski, Philippe; Masip Bruin, Javier
    Computer networks
    Date of publication: 2010-12-03
    Journal article

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    Reducing the effects of routing inaccuracy by means of prediction and an innovative link-state cost  Open access

     Masip Bruin, Javier; Marín Tordera, Eva; Yannuzzi, Marcelo; Serral Gracia, Rene; Sanchez Lopez, Sergio
    IEEE communications letters
    Date of publication: 2010-05
    Journal article

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    The routing inaccuracy problem is one of the major issues impeding the evolution and deployment of Constraint- Based Routing (CBR) techniques. This paper proposes a promising CBR strategy that combines the strengths of prediction with an innovative link-state cost. The latter explicitly integrates a two-bit counter predictor, with a novel metric that stands for the degree of inaccuracy (seen by the source node) of the state information associated with the links along a path. In our routing model, Link-State Advertisements (LSAs) are only distributed upon topological changes in the network, i.e., the state and availability of network resources along a path are predicted from the source rather than updated through conventional LSAs. As a proof-of-concept, we apply our routing strategy in the context of circuit-switched networks. We show that our approach considerably reduces the impact of routing inaccuracy on the blocking probability, while eliminating the typical LSAs caused by the traffic dynamics in CBR protocols.

  • PREPARACIÓ PROPOSTA X-AGON AL FP7

     Marín Tordera, Eva; Serral Gracia, Rene; Yannuzzi, Marcelo; Masip Bruin, Javier
    Participation in a competitive project

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  • PREPARACIÓ PROPOSTA OASIS AL FP7

     Serral Gracia, Rene; Yannuzzi, Marcelo; Marín Tordera, Eva; Masip Bruin, Javier
    Participation in a competitive project

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  • PREPARACIÓ PROPOSTA HAROON AL FP7

     Serral Gracia, Rene; Yannuzzi, Marcelo; Marín Tordera, Eva; Masip Bruin, Javier
    Participation in a competitive project

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  • PREPARACIÓ PROPOSTA X-TALK AL FP7

     Marín Tordera, Eva; Serral Gracia, Rene; Yannuzzi, Marcelo; Masip Bruin, Javier
    Participation in a competitive project

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  • TEC2010-09498-E (WWIC 2011)

     Yannuzzi, Marcelo; Martinez Manzanilla, Anny Gabriela; Serral Gracia, Rene; Marín Tordera, Eva; Sanchez Lopez, Sergio; Ramirez Almonte, Wilson; Masip Bruin, Javier
    Participation in a competitive project

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  • FP7-258300-ONE

     Masip Bruin, Javier; Serral Gracia, Rene; Martinez Manzanilla, Anny Gabriela; Marín Tordera, Eva; Ramirez Almonte, Wilson; Yannuzzi, Marcelo
    Participation in a competitive project

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  • ONE:PREPARCIÓN PROPUESTA AL FP7

     Serral Gracia, Rene; Masip Bruin, Javier; Marín Tordera, Eva; Yannuzzi, Marcelo
    Participation in a competitive project

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  • DISEÑO MULTINIVEL DE NUEVAS ARQ.Y PROTOCOLOS PARA REDES MULTIDOMINIO

     Ramirez Almonte, Wilson; German Duarte, Martin; Sanchez Lopez, Sergio; Yannuzzi, Marcelo; Serral Gracia, Rene; Marín Tordera, Eva; Martinez Manzanilla, Anny Gabriela; Masip Bruin, Javier
    Participation in a competitive project

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  • Diseno Multinivel de Nuevas Arquitecturas y Protocolos para Redes Multidominio - CICYT

     Masip Bruin, Javier; Yannuzzi, Marcelo; Serral Gracia, Rene; Sanchez Lopez, Sergio; Marín Tordera, Eva; Castro Casales, Alberto; German Duarte, Martin
    Participation in a competitive project

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    The Effects of Optimized Regenerator Allocation in Trans-lucent Networks under Inaccurate Physical information  Open access

     Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier; Sanchez Lopez, Sergio; Martínez, Ricardo; Muñoz González, Raul; Casellas, Ramón; Maier, Guido
    International Conference on Optical Networking Design and Modeling
    Presentation's date: 2010-02-02
    Presentation of work at congresses

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    Optimized regenerator allocation techniques select which of the already installed regenerators in a translucent network must be used in order to maximize the quality of the optical signal while minimizing the opaqueness of the network. Unfortunately, the performance of an optimized regenerator allocation strategy strongly depends on the accuracy of the physical-layer information. In this paper, we investigate the effects of optimized regenerator allocation techniques when the physical-layer information is inaccurate. According to the performed experiments, we conclude that mostly of the current techniques of regenerator usage optimization are only possible when perfect knowledge of physical information is available. Hence, new regenerator allocation schemes taking into account the inherent inaccuracy in the physical-layer information need to be designed.

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    Quality of experience enforcement in wireless networks  Open access

     Serral Gracia, Rene; Yannuzzi, Marcelo; Marín Tordera, Eva; Masip Bruin, Javier; Sanchez Lopez, Sergio
    International Conference on Wired/Wireless Internet Communications
    Presentation's date: 2010-06-03
    Presentation of work at congresses

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    In this paper we present a Multimedia Wireless Management System, which can be used on-line to assess and guarantee the quality of multimedia traffic in a wireless network. The proposed platform uses both network and application layer metrics to build up a scalable quality assessment of multimedia traffic. Moreover, the system provides traffic provisioning capabilities by coordinating the network access and usage both from the wireless node and from the network access point. These two combined features permit our platform to guarantee a satisfactory multimedia user experience in wireless environments. We evaluate our proposal by issuing an experimental deployment in a testbed and performing a series of tests under different network situations to demonstrate the Quality of Experience guaranties of our system. The results show that the quality of video perceived by end-users is considerably improved compared to the typical wireless network.

    Postprint (author’s final draft)

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    An overview of quality of experience measurement challenges for video applications in IP Networks  Open access

     Serral Gracia, Rene; Cerqueira, E; Curado, Marilia; Yannuzzi, Marcelo; Monteiro, Edmundo; Masip Bruin, Javier
    International Conference on Wired/Wireless Internet Communications
    Presentation's date: 2010-06-04
    Presentation of work at congresses

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    The increase in multimedia content on the Internet has created a renewed interest in quality assessment. There is however a main difference from the traditional quality assessment approaches, as now, the focus relies on the user perceived quality, opposed to the network centered approach classically proposed. In this paper we overview the most relevant challenges to perform Quality of Experience (QoE) assessment in IP networks and highlight the particular considerations necessary when compared to alternative mechanisms, already deployed, such as Quality of Service (QoS). To assist on the handling of such challenges we first discuss the different approaches to Quality of Experience assessment along with the most relevant QoE metrics, and then we discuss how they are used to provide objective results about user satisfaction.

    Postprint (author’s final draft)

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    Inter-domain Routing in Optical Networks with Wavelength Converters  Open access

     Beshir, Anteneh; Yannuzzi, Marcelo; Kuipers, Fernando
    IEEE International Conference on Communications
    Presentation's date: 2010-05
    Presentation of work at congresses

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    With the increasing deployment of wavelengthdivision multiplexing (WDM) optical networks, the need for advanced lightpath provisioning algorithms and protocols in a multi-domain setting is becoming evident. In order to increase efficiency by relaxing the wavelength continuity constraint in WDM optical networks, wavelength converters are often placed at certain nodes in the network. In this paper, we study the efficiency of using converters in a multi-domain setting. We have made simple but important modifications to existing optical inter-domain routing protocols in order to utilize the power of wavelength converters and have tested their performance. These modifications can be seamlessly integrated into these protocols (i.e., without changing their algorithmic aspects) to significantly reduce their blocking ratio. We also show that there is a clear performance difference among the considered protocols.

    Postprint (author’s final draft)

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    Simple network management provisioning based on quality of experience feedback  Open access

     Serral Gracia, Rene; Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier; Sanchez Lopez, Sergio
    Workshop in G/MPLS Networks
    Presentation's date: 2010-07-06
    Presentation of work at congresses

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    This paper presents a promising Autonomic Network Management System (ANMS) that allows Service Providers (SPs) to perform efficient network resource provisioning with their Network Operators (NOs). The novelty of our ANMS is that it offers an starting point to use the end-users perceived quality as a metric to manage the network resources. We show that our system is capable of achieving considerable reductions in the operational costs of SPs, while keeping proper bounds in the end-user satisfaction for the offered multimedia services.

    Postprint (author’s final draft)

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    A New Parametric Regenerator Allocation Scheme taking into account Inaccurate Physical Information  Open access

     Marín Tordera, Eva; Yannuzzi, Marcelo; Serral Gracia, Rene; Masip Bruin, Javier; Sanchez Lopez, Sergio
    15th European Conference on Networks and Optical Communications 5th Conference on Optical Cabling and Infrastructure
    Presentation's date: 2010-06-08
    Presentation of work at congresses

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    Regenerator allocation consists on selecting which of the already installed regenerators in a translucent network may be used according to the dynamic traffic requests in order to maximize the quality of the optical signal while minimizing the opaqueness of the network. A recent study has shown that the performance of the regenerator allocation techniques strongly depends on the accuracy of the physical-layer information. The reason of this physical inaccuracy is the drift suffered by the physical-layer parameters during the operation of the optical network. In these conditions, the performance of the Impairment Aware-Routing and Wavelength Assignment (IA-RWA) process might drop sharply when allocating regenerators inappropriately. In this paper, we propose new regenerator allocation schemes taking into account the inherent and unavoidable inaccuracy in the physical-layer information

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    Cross-talk effects on the Regenerator Allocation optimization  Open access

     Marín Tordera, Eva; Masip Bruin, Javier; Yannuzzi, Marcelo; Serral Gracia, Rene; Sanchez Lopez, Sergio
    International Congress on Ultra Modern Telecommunications and Control Systems and Workshops
    Presentation's date: 2010-10-19
    Presentation of work at congresses

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    This paper studies the impact of considering crosstalk effects in the IA-RWA process and in the regenerator allocation algorithms. First of all, we evaluate if the regenerator allocation optimization is still useful when the crosstalk effects are considered. For this end we improve a simple physical model which computes the quality of the signal factor for each optical connection. Until now this physical model was unaware of the physical layer impairments depending on the interference between different optical connections, such as the crosstalk. Following the same simple methodology we add the switching node crosstalk effect to the computation of the quality of the signal factor. Once the new physical model is enhanced we evaluate the impact of the crosstalk on the performance of IA-RWA algorithms that optimize the use of the regenerators; and also we evaluate the impact of different e wavelength assignation techniques.

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    Cross-layer multimedia quality enforcement through user aware information in wireless networks  Open access

     Serral Gracia, Rene; Yannuzzi, Marcelo; Marín Tordera, Eva; Masip Bruin, Javier; Sanchez Lopez, Sergio
    Workshop on Multilayer Netwoks
    Presentation's date: 2010-06-14
    Presentation of work at congresses

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    Quality assessment of multimedia traffic is a hot topic. In this paper we present a Multimedia Management System, which can be used on-line to assess and guarantee the quality of multimedia traffic in a wired and wireless network. The proposed platform uses both network and application layer metrics to build up a scalable quality assessment framework. The core of this framework provides means for traffic provisioning capabilities by coordinating the network access and usage both from the wireless node and from the network access point. These two combined features permit our platform to guarantee a satisfactory multimedia user experience. We evaluate our proposal by issuing an experimental deployment in a testbed and performing a series of tests under different network situations to demonstrate the Quality of Experience guaranties of our system. The results show that the quality of video perceived by endusers is considerably improved compared to the typical wireless network.

    Postprint (author’s final draft)

  • Quality of experience aware multimedia provisioning with cross-layer network management

     Serral Gracia, Rene; Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier; Sanchez Lopez, Sergio
    IEEE Global Communications Conference
    Presentation's date: 2010-12-07
    Presentation of work at congresses

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  • Effcient network performance assessment using Inter-Packet Arrival Times

     Serral Gracia, Rene; Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier; Sanchez Lopez, Sergio
    IEEE Global Communications Conference
    Presentation's date: 2010-12-06
    Presentation of work at congresses

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    Regenerator allocation in WDM networks with uncertainities in the Q factor  Open access

     Marín Tordera, Eva; Yannuzzi, Marcelo; Masip Bruin, Javier; Serral Gracia, Rene; Sanchez Lopez, Sergio
    Workshop on Multilayer Networks
    Presentation's date: 2010-06-15
    Presentation of work at congresses

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    The performance of the regenerator allocation algorithms in WDM networks strongly depends on the accuracy of the physical-layer information such as the Q factor. In a translucent WDM network the already installed regenerators along the lightpath are allocated based on the physical information (Q factor) in order to maximize the quality of the optical signal while minimizing the opaqueness of the network. The Q factor used by the IA-RWA algorithms is usually inaccurate due to the drift suffered by the physical-layer parameters during the operation of the optical network. In this scenario the allocation of regenerators is not optimized and then the performance of the network is worsened. New regenerator allocation schemes should be proposed in order of counteracting the inherent and unpredictable uncertainty in the physical-layer information.

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    Managing Interdomain Traffic in Latin America: A New Perspective based on LISP  Open access

     Yannuzzi, Marcelo; Masip Bruin, Javier; Grampin Castro, Eduardo; Gagliano Molla, Roque; Castro Casales, Alberto; German Duarte, Martin
    IEEE communications magazine
    Date of publication: 2009-07
    Journal article

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    The characteristics of Latin American network infrastructures have global consequences, particularly in the area of interdomain traffic engineering. As an example, Latin America shows the largest de-aggregation factor of IP prefixes among all regional Internet registries, being proportionally the largest contributor to the growth and dynamics of the global BGP routing table. In this article we analyze the peculiarities of LA interdomain routing architecture, and provide up-to-date data about the combined effects of the multihoming and TE practices in the region. We observe that the Internet Research Task Force initiative on the separation of the address space into locators and identifiers can not only alleviate the growth and dynamics of the global routing table, but can also offer appealing TE opportunities for LA. We outline one of the solutions under discussion at the IRTF, the Locator/Identifier Separation Protocol, and examine its potential in terms of interdomain traffic management in the context of LA. The key advantage of LISP is its nondisruptive nature, but the existing proposals for its control plane have some problems that may hinder its possible deployment. In light of this, we introduce a promising control plane for LISP that can solve these issues, and at the same time has the potential to bridge the gap between intradomain and interdomain traffic management.

  • Proposta X-TALK Call 5 ICT

     Serral Gracia, Rene; Yannuzzi, Marcelo; Marín Tordera, Eva; Masip Bruin, Javier
    Participation in a competitive project

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  • GIFT 2008-08043 PATH-STATE VECTORS

     Yannuzzi, Marcelo
    Participation in a competitive project

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  • COST ACTION IC0806

     Serral Gracia, Rene; Yannuzzi, Marcelo; Marín Tordera, Eva; Martinez Manzanilla, Anny Gabriela; Ramirez Almonte, Wilson; Masip Bruin, Javier
    Participation in a competitive project

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  • Intelligent Monitoring Control and Security of Critical Infrastructure Systems

     Yannuzzi, Marcelo; Masip Bruin, Javier; Serral Gracia, Rene
    Participation in a competitive project

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  • XARXA MULTINIVELL : IP SOBRE XARXA DE TRANSPORTS (TEC2008-02552-E/TEC)

     Sanchez Lopez, Sergio; Castro Casales, Alberto; Serral Gracia, Rene; German Duarte, Martin; Yannuzzi, Marcelo; Marín Tordera, Eva; Masip Bruin, Javier
    Participation in a competitive project

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  • Path-State Vectors - Cisco

     Serral Gracia, Rene; Yannuzzi, Marcelo; Masip Bruin, Javier
    Participation in a competitive project

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    Performance of translucent optical networks under dynamic traffic and uncertain physical-layer information  Open access

     Yannuzzi, Marcelo; Quagliotti, Marco; Maier, Guido; Marín Tordera, Eva; Masip Bruin, Javier; Sanchez Lopez, Sergio; Erangoli, Walter; Tamiri, G
    International Conference on Optical Networking Design and Modeling
    Presentation's date: 2009-02
    Presentation of work at congresses

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    This paper investigates the performance of translucent Optical Transport Networks (OTNs) under different traffic and knowledge conditions, varying from perfect knowledge to drifts and uncertainties in the physical-layer parameters. Our focus is on the regular operation of a translucent OTN, i.e., after the dimensioning and regenerator placement phase. Our contributions can be summarized as follows. Based on the computation of the Personick’s Q factor, we introduce a new methodology for the assessment of the optical signal quality along a path, and show its application on a realistic example. We analyze the performance of both deterministic and predictive RWA techniques integrating this signal quality factor Q in the lightpath computation process. Our results confirm the effectiveness of predictive techniques to deal with the typical drifts and uncertainties in the physical-layer parameters, in contrast to the superior efficacy of deterministic approaches in case of perfect knowledge. Conversely to most previous works, where all wavelengths are assumed to have the same characteristics, we examine the case when the network is not perfectly compensated, so the Maximum Transmission Distance (MTD) of the different wavelength channels may vary. We show that blocking might increase dramatically when the MTD of the different wavelength channels is overlooked.

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    Avoiding Path-Vectors in Multi-Domain Optical Networks  Open access

     Yannuzzi, Marcelo; Masip Bruin, Javier
    Optical Fiber Communication Conference and Exposition
    Presentation's date: 2009-03
    Presentation of work at congresses

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    We show that a modified version of a path-vector protocol can drastically reduce the blocking and converge significantly faster, while exchanging less number of routing messages both during failure-free conditions and during a convergence.

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    Understanding IPv4 prefix de-aggregation: challenges for routing scalability  Open access

     Gagliano Molla, Roque; Grampin Castro, Eduardo; Baliosian, Javier; Masip Bruin, Javier; Yannuzzi, Marcelo
    IFIP/IEEE International Symposium on Integrated Network Management Workshops
    Presentation's date: 2009-06
    Presentation of work at congresses

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    The Internet has become a vast and complex infrastructure. One of the aspects of deeper concern in the community is routing scalability, which involves both the size and dynamics of the global Internet routing table. Many Future Internet initiatives stand for “clean slate” or disruptive approaches to overcome this issue; nevertheless, network operators need evolutionary solutions. In this paper we put forward a characterization of the IP prefix de-aggregation factor focussing on the Latin American region, where we found that a significant contribution to the growth of the routing table could be prevented by improving BGP configuration. In the context of our participation in the LISP+ALT testbed (an evolutionary Future Internet initiative), we identify initial management requirements for its deployment, according to our findings regarding the size and dynamics of the routing table.

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    The Minimum Coincidence Routing Approach in Wavelength-Routed Optical WDM Networks  Open access

     Masip Bruin, Javier; German Duarte, Martin; Castro Casales, Alberto; Marín Tordera, Eva; Serral Gracia, Rene; Sanchez Lopez, Sergio; Yannuzzi, Marcelo; Gagliano Molla, Roque; Grampin Castro, Eduardo
    IEEE/IFIP Latin American Network Operations and Management Symposium
    Presentation's date: 2009-10
    Presentation of work at congresses

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    Management is a critical issue in optical networks. Highly impacting in management, routing in optical networks, is often decoupled into both the path selection and the wavelength assignment problems. In the former, shortest path based approaches are often applied to compute paths. Although such approaches offer advantages in terms of network loading, they are restricted by the fact, that routes are selected without taking into account parameters pertaining to any explicit and desired service guarantees. Thus, the wavelength assignment process may assign a non-optimal wavelength with respect to incoming traffic requirements and any associated quality of service specifications. This paper addresses the lightpath selection problem by proposing a novel route selection scheme where routes are determined based upon the twin criteria of minimizing the number of hops and balancing the network load, resulting in a reduction in both network congestion and blocking probability.

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    Optical Multi-Domain Routing  Open access

     Masip Bruin, Javier; Yannuzzi, Marcelo
    Optical Fiber Communication Conference and Exposition
    Presentation's date: 2009-03
    Presentation of work at congresses

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    Optical networks provide a clear opportunity to redesign the multi-domain routing paradigm. This paper reviews the current limitations in multi-domain routing as well as some of the research lines in the optical area.

  • On the challenges of finding two link-disjoint lightpaths of minimum total weight across an optical network

     German Duarte, Martin; Castro Casales, Alberto; Masip Bruin, Javier; Yannuzzi, Marcelo; Martínez, Ricardo; Casellas, Ramón; Muñoz González, Raul
    14th European Conference on Networks and Optical Communications
    Presentation's date: 2009-06-10
    Presentation of work at congresses

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    OBGP+: An improved path-vector protocol for multi-domain optical networks  Open access

     Yannuzzi, Marcelo; Masip Bruin, Javier; Sanchez Lopez, Sergio; Marín Tordera, Eva
    Optical switching and networking
    Date of publication: 2009-04
    Journal article

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    One of the essential components for the dynamic provisioning of lightpaths across multiple domains is the Routing and Wavelength Assignment (RWA) strategy adopted. The consolidation that path-vector protocols have had in practice, has motivated the optical extension to BGP (OBGP). We claim, however, that a routing model mostly centered on the exchange of reachability information–like the one we have today with BGP or the one offered by OBGP–will not be sufficient for multi-domain optical networks. Routing domains must be able to exchange both reachability as well as aggregated Path-State Information (PSI). Understanding that this is a missing piece in the routing models provided by BGP and OBGP is easy nowadays, but contributing with solutions capable of highly improving the performance of a path-vector without impacting on key aspects of the protocol–fundamentally, its scalability, its convergence properties, and the number of routing messages exchanged between domains–is a challenging task. In this paper we propose OBGP +, which is a very simple extension of a path-vector protocol supporting the computation and advertisement of PSI between optical domains. The PSI that we propose to use is highly condensed in the form of a single integer value. In order to avoid the typical increase in the number of routing messages associated with the update of PSI, we propose to piggy-back the updates in non-dummy Keepalive messages exchanged between OBGP+ neighbors. Extensive simulations reveal that, despite its simplicity: (i) OBGP+ is able to drastically reduce the blocking experienced with a path-vector protocol like OBGP; (ii) OBGP+ needs much less number of routing messages than OBGP to achieve such performance; and (iii) the convergence and restoration features of OBGP+ are also better than those of OBGP, which is particularly important for connections that lack a protection path.