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  • 151.
    Monti, Paolo
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101). KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101). KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. Istanbul Technical University, Turkey.
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101). KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101). KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Fumagalli, Andrea
    The University of Texas at Dallas, US.
    New Dimensions for Survivable Service Provisioning in Optical Backbone and Access Networks2012In: Resilient Optical Network Design: Advances in Fault-Tolerant Methodologists / [ed] Mark Leeson and Yousef Kavian, IGI Global, 2012, p. 227-252Chapter in book (Refereed)
    Abstract [en]

    Originally, networks were engineered to provide only one type of service, i.e. either voice or data, soonly one level of resiliency was requested. This trend has changed, and today’s approach in serviceprovisioning is quite different. A Service Level Agreement (SLA) stipulated between users and serviceproviders (or network operators) regulates a series of specific requirements, e.g., connection set-up timesand connection availability that has to be met in order to avoid monetary fines. In recent years this hascaused a paradigm shift on how to provision these services. From a “one-solution-fits-all” scenario, wewitness now a more diversified set of approaches where trade-offs among different network parameters(e.g., level of protection vs. cost and/or level of protection vs. blocking probability) play an important role.This chapter aims at presenting a series of network resilient methods that are specifically tailored for adynamic provisioning with such differentiated requirements. Both optical backbone and access networksare considered. In the chapter a number of provisioning scenarios - each one focusing on a specificQuality of Service (QoS) parameter - are considered. First the effect of delay tolerance, defined as theamount of time a connection request can wait before being set up, on blocking probability is investigatedwhen Shared Path Protection is required. Then the problem of how to assign “just-enough” resources tomeet each connection availability requirement is described, and a possible solution via a Shared PathProtection Scheme with Differentiated Reliability is presented. Finally a possible trade off between deploymentcost and level of reliability performance in Passive Optical Networks (PONs) is investigated. 

    The presented results highlight the importance of carefully considering each connection’s QoS parameterswhile devising a resilient provisioning strategy. By doing so the benefits in terms of cost saving andblocking probability improvement becomes relevant, allowing network operators and service providersto maintain satisfied customers at reasonable capital and operational expenditure levels.

  • 152.
    Monti, Paolo
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Costa, J. C. W. A.
    Farias, F. S.
    Fiorani, M.
    Nilson, Mats
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Tombaz, Sibel
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Västberg, Anders
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Green mobile backhaul in heterogeneous wireless deployments2013In: Asia Communications and Photonics Conference, ACP 2013, Optical Society of America, 2013Conference paper (Refereed)
    Abstract [en]

    This tutorial first introduces and describes different backhaul technological and architectural options (i.e., fiber-, microwave-, and copper-based), then it discusses their impact on the energy consumption of current and future heterogeneous mobile wireless access deployments.

  • 153.
    Monti, Paolo
    et al.
    KTH.
    Li, Y.
    KTH. Beijing Univ Posts & Telecommun, Beijing, Peoples R China..
    Martensson, J.
    RISE Acreo, Kista, Sweden..
    Fiorani, M.
    Ericsson Res, Stockholm, Sweden..
    Skubic, B.
    Ericsson Res, Stockholm, Sweden..
    Ghebretensae, Z.
    Ericsson Res, Stockholm, Sweden..
    Wosinska, Lena
    KTH.
    A Flexible 5G RAN Architecture with Dynamic Baseband Split Distribution and Configurable Optical Transport2017In: 2017 19TH INTERNATIONAL CONFERENCE ON TRANSPARENT OPTICAL NETWORKS (ICTON), Institute of Electrical and Electronics Engineers (IEEE), 2017Conference paper (Refereed)
  • 154.
    Monti, Paolo
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Muhammad, Ajmal
    Linköpings Tekniska Högskola.
    Cerutti, Isabella
    Scuola Superiore Sant'Anna.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Castoldi, Piero
    Scuola Superiore Sant'Anna.
    Tzanakaki, Anna
    Athens Information Technology.
    Energy-efficient lightpath provisioning in a static WDM network with dedicated path protection2011In: International Conference on Transparent Optical Networks, IEEE , 2011, p. 1-5Conference paper (Refereed)
    Abstract [en]

    The interest in the energy consumption of communication networks has risen in the recent years. In an effort to tackle this problem, several approaches have been presented to reduce the power consumed by the entire network infrastructure, including optical transport. Most of the solutions studied and proposed in the literature, however, pay little or no attention to the power consumed to ensure the resiliency of the overall network. In wavelength division multiplexing (WDM) networks resilient to single failures, an innovative strategy that can be adopted to reduce power consumption entails setting to sleep mode the optical devices supporting solely protection lightpaths. To take full advantage of this strategy, it is important to optimally route the lightpaths so that the number of devices supporting exclusively protection lightpaths is maximized. An optimal solution for this provisioning problem was previously presented, but features a limited scalability with the network size. This paper first proposes a scalable and efficient heuristic that chooses the route of the working and protection lightpaths with the aim to maximize the power saving. The performance of the heuristic is compared with the optimal solution and a sensitivity analysis of the drained power is carried out by considering a variety of networking scenarios. Up to 20% of the network links can be set to sleep leading to significant power saving, especially at low load and when the power consumption in sleep mode is negligible.

  • 155.
    Monti, Paolo
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Natalino, Carlos
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Ahmed, Jawwad
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Frances, Renato
    Restoring optical cloud services using relocation2014Conference paper (Refereed)
    Abstract [en]

    Optical cloud is a very popular concept by which storage and computing resources (i.e., IT resources) are distributed over different datacenter (DC) locations interconnected via high-speed optical wavelength division multiplexing (WDM) links. In this paradigm cloud services are provisioned in an anycast fashion, where only the source node needs to be specified in the routing and resource assignment phase, while any DC (with enough IT resources) can be used to accommodate a cloud service. Anycast provisioning has a number of advantages already recognized by optical cloud providers [1][2]. This kind of provisioning paradigm allows, for example, for the live relocation of the already provisioned cloud services, referred to as the service relocation concept. It means that if the DC location is not essential for the execution of a certain cloud service, multiple relocations of the job to other DC locations are possible. This allows for a more efficient management of both the cloud and the transport network resources. Service relocation has also the potential to bring an extra degree of flexibility to survivability strategies. By providing the option for relocating a cloud service it is possible to use a backup path terminating at a DC that is different from the one used by the primary path. This benefit has been assessed in the literature showing the ability to improve resources efficiency by using service relocation in conjunction with path protection strategies [1]. Another instance in which service relocation might be beneficial is when it is combined with restoration-based survivability strategies. These strategies are very efficient in using backup resources, i.e., they are dynamically provisioned only upon a failure, but restoration-based approaches suffer from a certain risk that the backup network resources might not be available when needed [3]. Service relocation can potentially alleviate this problem. This talk presents a study where the objective is to inves- igate if relocating a cloud service disrupted by a network failure is beneficial in terms of both restorability and average connection availability. To this end the talk will present a number of results based on the solution of an efficient and scalable heuristic algorithm able to jointly solve the restoration and service relocation problem. These results are also benchmarked against the performance of an integer linear programming (ILP) model [4] optimizing the same objective function as the heuristic. In summary it can be concluded that by using relocation the average service availability can be significantly improved requiring only a minimal fraction of the cloud services to be relocated. In addition the proposed heuristic behaves very closely to the optimal ILP results in terms of both restorability and average connection availability.

  • 156.
    Monti, Paolo
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Tombaz, Sibel
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Zander, Jens
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Mobile backhaul in heterogeneous network deployments: Technology options and power consumption2012In: 14th International Conference on Transparent Optical Networks, 2012, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Mobile communication networks account for 0.5% of the global energy consumption, a value that is expected to double within the next five years. For this reason, means of reducing the energy consumption in cellular mobile radio networks has recently gained great interest within the research community. In mobile networks the backhaul contribution to the total power consumption is usually neglected because of its limited impact compared to that of the radio base stations. However, meeting the almost exponential increase in mobile data traffic requires a large number of (mainly small) base stations. This means that backhaul networks will take a significant share of the cost and the energy consumption in future systems. Their actual contribution to the energy consumption will depend on the radio base station deployment scenario as well as on the technology and topology choices for the backhaul itself. This paper presents an initial assessment of the power consumption of two established backhaul technologies, i.e., fiber and microwave. For the microwave case, three backhaul topologies are considered, i.e., tree, ring and star, while for the fiber case only one topology is analysed, i.e., a dedicated point-to-point star. The presented results, assuming off-the-shelf products and based on todays network capacity levels, confirm the importance of considering the backhaul when minimizing the total power consumption in heterogeneous network scenarios. They also show the impact of the basic technology and topology choices of the backhaul for minimizing total power consumption.

  • 157.
    Monti, Paolo
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Wiatr, Pawel
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics.
    Jirattigalachote, Amornrat
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics.
    Trading Power Savings for Blocking Probabilityin Dynamically Provisioned WDM Networks2010Conference paper (Other academic)
    Abstract [en]

    In those networking scenarios (e.g., the stationary/mobile wireless paradigm) where limited energy storagecapabilities is a limiting factor, power efficiency has been studied extensively for a long time. In the last fewyears, the steadily growing power consumption figures of ICT [1][2] along with a recent public awareness of thepossible environmental effects, broadened the focus of the research efforts towards more power conscioussolutions also for wired networks. One promising solution going in this direction is represented by transparentwavelength division multiplexing (WDM) networks, where all-optical circuits (or lightpaths) carry the networktraffic from the source to the destination node in the optical domain, i.e. without any optical-to-electrical(O-E-O) conversion. To further improve network power efficiency, several approaches have been proposed inthe literature attempting to reduce the power consumption in transparent WDM networks [3][4]. Among them,power aware (PA) routing and wavelength assignment (RWA) algorithms are receiving a lot of attention. Onepossible solution for the PA-RWA problem is to limit the number of devices in the network that need to bepowered-on to support the lightpath requests [5]. These methods, however, have an adverse impact on the lengthof the provisioned lightpaths. In order to efficiently use as much powered-on network resources as possible, thepath length is, on average, longer than the one found with traditional (and less power efficient) shortest pathsolutions. This is in contradiction with the goal of classical RWA algorithms that tend to minimize the resourceusage (i.e., wavelengths and fibers) within the network, in order to minimize the blocking probability. Whenavailability of network resources becomes something that cannot be overlooked, a trade off needs to be assessedbetween power savings and blocking probability.In this talk, a non-conventional solution to the PA-RWA problem is presented. It is based on the intuitionthat, in some cases, relaxing the power minimization constraint can have beneficial effects on the overallnetwork performance, i.e., it can contribute to the reduction of resource fragmentation in the network and, in thisway, lower the blocking probability. The proposed algorithm leverages on a cost function that considers both thepower status of network elements (in this particular case the in-line optical amplifiers on fiber links only) and theinformation about wavelength usage. The algorithm has been tested using a Pan-European core network (i.e.,COST 239). Performance results confirm the presence of a trade-off between energy saving and blockingprobability. They also suggest that a “binary” approach using only the powered-on/powered-off informationmight not always be the best choice.

  • 158.
    Muchanga, Americo Francisco
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Orava, Fredrik
    Haralson, Joanna
    Inter-domain routing in optical networks2005In: OPTICAL NETWORKS AND TECHNOLOGIES, 2005, Vol. 164, p. 263-270Conference paper (Refereed)
    Abstract [en]

    In this paper we present a mechanism for obtaining an abstraction of network topology in optical networks in order to compute an end-to-end lightpath across multiple domains.

  • 159.
    Muchanga, Americo
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Orava, Fredrik
    KTH, School of Information and Communication Technology (ICT).
    Inter-layer communication for improving restoration time in optical networks2006In: Optical Fiber Communication Conference, 2006 and the 2006 National Fiber Optic Engineers Conference. OFC 2006, WASHINGTON: OPTICAL SOC AMERICA , 2006, p. 1455-1461Conference paper (Refereed)
    Abstract [en]

    The restoration time in high capacity optical networks has to be kept as short as possible in order to avoid a huge loss of data. This paper discusses several methods to improve restoration time in optical networks and we propose the use of error codes that will trigger immediately the appropriate layer recovery mechanism, which is the best to handle a given fault.

  • 160.
    Muchanga, Américo
    et al.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Bagula, Antoine B
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Inter-layer communication for faster restoration in a 10Gigabit Ethernet based network2006In: Reliability of Optical Fiber Components, Devices, Systems, and Networks III, 2006, Vol. 6193Conference paper (Refereed)
    Abstract [en]

    The restoration time in high capacity optical networks has to be kept as short as possible in order to avoid a huge loss of data. This paper discusses several methods to improve restoration time in optical networks and we propose mechanisms of implementing such inter-layer communication in order to decrease restoration time for a 10Gigabit Ethernet based network.

  • 161.
    Muchanga, Américo Francisco
    et al.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Bagula, Antoine
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    On using fast signalling to improve restoration in multilayer networks2006In: Optical Fiber Communication and the National Fiber Optic Engineers Conference, 2007. OFC/NFOEC 2007., 2006, p. 1-12Conference paper (Refereed)
    Abstract [en]

    We present a fast signalling scheme where intra-layer signalling and inter-layer communication are used to reduce the recovery operation time. Simulation reveals the efficiency of the scheme compared to normal signalling strategies.

  • 162.
    Muchanga, Américo Francisco
    et al.
    KTH, School of Information and Communication Technology (ICT).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Orava, Fredrik
    KTH, School of Information and Communication Technology (ICT).
    Providing QoS in end to end Optical Networking. 2006Report (Other academic)
  • 163.
    Muchanga, Américo
    et al.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Orava, Fredrik
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Haralson, Joanna
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Requirements for interdomain routing in optical networks2005In: National Fiber Optic Engineers Conference (NFOEC) 2005, Optical Society of America, 2005Conference paper (Refereed)
    Abstract [en]

    In this paper we present a mechanism for obtaining an abstraction of network topology in optical networks in order to compute an end-to-end lightpath across multiple domains in GMPLS networks. We also propose changes to BGP in order to carry the abstracted information. Furthermore we use Opnet to simulate MPLS operation as a special case of GMPLS.

  • 164. Muhammad, A.
    et al.
    Forchheimer, Robert
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Impairment-Aware Dynamic Provisioning in WDM Networks with Set-up Delay Tolerance and Holding-time Awareness2011In: 2011 17th IEEE International Conference on Networks (ICON), 2011, p. 213-218Conference paper (Refereed)
    Abstract [en]

    We study a dynamic WDM network with nonideal components in the physical layer which uses an impairment-aware routing and wavelength (RWA) algorithm for connection provisioning. We investigate the reduction in blocking probability (BP) by utilizing service Level Agreement (SLA) metric i.e. setup delay tolerance during connection provisioning. Furthermore, we explore the improvement in the network performance by efficiently utilizing the knowledge of the connections holding-time, another metric of SLA. Keeping in mind that BP reduction can be obtained by set-up delay tolerance [1] our focus is to investigate how set-up delay tolerance combined with holding-time awareness can improve BP performance caused by physical impairment. Our simulation results confirm that significant improvement can be achieved by holding-time aware connection provisioning compared to the unaware holding-time case. Moreover as expected, set-up delay tolerance can reduce BP even without knowledge of connections holding-time.

  • 165. Muhammad, A.
    et al.
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab). University of Zagreb, Croatia.
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Forchheimer, R.
    An optimization model for dynamic bulk provisioning in elastic optical networks2014In: Asia Communications and Photonics Conference, ACPC 2014, 2014Conference paper (Refereed)
    Abstract [en]

    We investigate benefits of setup-delay tolerance in elastic optical networks and propose an optimization model for dynamic and concurrent connection provisioning. Simulation shows that the proposed strategy offers significant improvement of the network blocking performance.

  • 166. Muhammad, A.
    et al.
    Skorin-Kapov, N.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Manycast and anycast routing for replica placement in datacenter networks2015In: European Conference on Optical Communication, ECOC, Institute of Electrical and Electronics Engineers (IEEE), 2015Conference paper (Refereed)
    Abstract [en]

    Inter-datacenter networks need to support datacenters communication with the end-users, as well as content replication and synchronization between datacenters. This paper presents an integrated routing and replica placement strategy for WDM inter-datacenter networks resulting in reduced overall network resource consumption.

  • 167. Muhammad, Ajmal
    et al.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Forchheimer, Robert
    Effect of Delay Tolerance in WDM Networks with Differentiated Services2011Conference paper (Refereed)
    Abstract [en]

    We study a dynamic WDM network supporting different service classes (SC) containing applications having similar setup delay tolerance. By utilizing delay tolerance we propose scheduling strategies able to significantly reduce blocking probability of each SC.

  • 168. Muhammad, Ajmal
    et al.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Forchheimer, Robert
    Service Differentiated Provisioning in Dynamic WDM Networks Based on Set-Up Delay Tolerance2013In: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 5, no 11, p. 1250-1261Article in journal (Refereed)
    Abstract [en]

    Optical networks are expected to provide a unified platform for a diverse set of emerging applications (three-dimensional TV, digital cinema, e-health, grid computing, etc). The service differentiation will be an essential feature of these networks. Considering the fact that users have different levels of patience for different network applications, referred to as set-up delay tolerance, it will be one of the key parameters for service differentiation. Service differentiation based on set-up delay tolerance will not only enable network users to select an appropriate service class (SC) in compliance with their requirements, but will also provide an opportunity to optimize the network resource provisioning by exploiting this information, resulting in an improvement in the overall performance. Improvement in network performance can be further enhanced by exploiting the connection holding-time awareness. However, when multiple classes of service with different set-up delay tolerances are competing for network resources, the connection requests belonging to SCs with higher set-up delay tolerance have better chances to grab the resources and leave less room for the others, resulting in degradation in the blocking performance of less patient customers. This study proposes different scheduling strategies for promoting the requests belonging to smaller set-up delay tolerance SCs, such as giving priority, reserving some fraction of available resources, and augmenting the research space by providing some extra paths. Extensive simulation results show that 1) priority in the rescheduling queue is not always sufficient for eradicating the degradation effect of high delay tolerant SCs on the provisioning rate of the most stringent SC, and 2) by utilizing the proposed strategies, resource efficiency and overall network blocking performance improve significantly in all SCs.

  • 169. Muhammad, Ajmal
    et al.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Forchheimer, Robert
    Trading Quality of Transmission for Improved Blocking Performance in All-Optical Networks2013In: IEEE/OSA/SPIE Proceedins, Asia Communications and Photonics Conference, ACP2013, 2013Conference paper (Refereed)
    Abstract [en]

    We propose a connection provisioning strategy in dynamic all-optical networks, which exploit the possibility to allow a tolerable signal quality degradation during a small fraction of holding-time resulting in a significant improvement of blocking performance.

  • 170.
    Muhammad, Ajmal
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Fiorani, Matteo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Joint Optimization of Resource Allocation for Elastic Optical Intra-Datacenter Network2016In: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 20, no 9, p. 1760-1763Article in journal (Refereed)
    Abstract [en]

    The ever-increasing demand for cloud services is posing serious challenges to the scalability of the computing, storing, and networking infrastructure deployed inside the datacenters. To address these challenges, we formulate the integer linear program (ILP) model to minimize the spectrum and the switch port usage by exploiting transparent multi-hop connection capability in elastic optical interconnect architecture for datacenters. The proposed ILP model not only takes into account the networking resources but also the other resources (such as computing and storage) in order to achieve a joint resource optimization in intra-datacenter networks. The optimal results show that substantial savings in both spectrum and switching resources can be achieved by properly tuning the objective function of the proposed optimization strategy.

  • 171. Muhammad, Ajmal
    et al.
    Furdek, Maria
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab). University of Zagreb, Croatia .
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Forchheimer, Robert
    Dynamic provisioning utilizing redundant modules in elastic optical networks based on architecture on demand nodes2014In: Optical Communication (ECOC), 2014 European Conference on, 2014, p. 1-3Conference paper (Refereed)
    Abstract [en]

    Survivable synthetic ROADMs are equipped with redundant switching modules to support failure recovery. The paper proposes a dynamic connection provisioning strategy which exploits these idle redundant modules to provision regular traffic resulting in a substantial improvement in the blocking performance.

  • 172. Muhammad, Ajmal
    et al.
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Cerutti, Isabela
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Castoldi, P.
    Reliability Differentiation in Energy Efficient Optical Networks with Shared Path Protection2013In: 2013 IEEE Online Conference on Green Communications, OnlineGreenComm 2013, IEEE , 2013, p. 64-69Conference paper (Refereed)
    Abstract [en]

    Energy and resource efficiency are two contrasting objectives to optimize in dynamic and survivable optical networks. Known solutions for improving the energy efficiency include the use of the shared path-protection (SPP) mechanism and of a low power consuming mode (i.e., sleep) for protection resources. On the other hand, resource efficiency can be improved by introducing the concept of Differentiated Reliability (DiR) which can be combined with SPP in order to match the level of provisioned protection resources to the reliability requirements for each specific demand. This paper assesses the energy efficiency of the DiR concept combined with SPP and sleep mode support. A multi-objective optimization algorithm is proposed with the intent of jointly optimizing the energy and resource efficiency when dynamically establishing lightpaths with specific reliability levels. Simulation results show that when the proposed multi-objective cost function is properly tuned, not only the SPP-based DiR approach reduces the blocking probability but it is also able to save power for any network load. By enabling sleep mode additional power savings can be achieved at low loads, leading to an overall saving of up to 25%.

  • 173.
    Muhammad, Ajmal
    et al.
    Linköpings tekniska högskola.
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Cerutti, Isabella
    Scuola Superiore Sant'Anna.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Castoldi, Piero
    Scuola Superiore Sant'Anna.
    Tzanakaki, Anna
    Athens Information Technology.
    Energy-Efficient WDM Network Planning with Dedicated Protection Resources in Sleep Mode2010In: Global Telecommunications Conference (GLOBECOM 2010), 2010 IEEE, IEEE , 2010, p. 1-5Conference paper (Refereed)
    Abstract [en]

    Energy-efficient optical networks are gaining momentum as environmental-friendly solutions with reduced operational costs. Energy-efficiency can be achieved by using devices in sleep mode, i.e., a low-power, inactive state in which devices can be suddenly waken-up upon occurrence of triggering events. This paper advocates a sleep mode option for the optical devices (e.g., amplifiers, optical switches) installed for protection purposes only. These devices can be put in sleep mode to reduce the network power consumption, but they can be promptly waken up (if necessary) upon a failure occurrence. This principle is proposed and applied in Wavelength Division Multiplexing (WDM) networks with dedicated-path protection to ensure survivability against single-link failures. The main contribution of the paper is the definition of the energy-efficient network planning problem for resilient WDM networks where optical devices can be configured in sleep mode. Optimal results of the integer linear programming (ILP) problem show savings of up to 25% in the overall power consumption.

  • 174.
    Muhammad, Ajmal
    et al.
    KTH, School of Information and Communication Technology (ICT).
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT).
    Samadi, P.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT).
    Bergman, K.
    Joint Allocation of IT and Connectivity Resources for Survivable Services in Geographically Distributed Metro Data Centers2018In: 2017 European Conference on Optical Communication (ECOC), Institute of Electrical and Electronics Engineers (IEEE), 2018, p. 1-3Conference paper (Refereed)
    Abstract [en]

    The paper proposes a survivable and programmable metro-scale converged inter- and intra-datacenter network architecture and exploits its unique features for allocating jointly IT and connectivity resources. The proposed dynamic provisioning strategy offers a substantial reduction of service request blocking.

  • 175.
    Mukherjee, Amitava
    et al.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Fault management for next-generation IP-over-WDM networks2005In: 2005 7th International Conference on Transparent Optical Networks, Vol 1, Proceedings, 2005, p. 423-428Conference paper (Refereed)
    Abstract [en]

    In this paper, we present a broad outline for fault management for next generation IP-over-WDM network. This system contains three different components namely fault detection, fault recovery and fairness service provisions for different needs. We also review various fault detection and fault recovery schemes for WDM networks.

  • 176. Nag, Avishek
    et al.
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Ruffini, Marco
    Exploiting Dual Homing in Access Networks to Improve Resiliency in Core Networks2016In: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 8, no 11, p. 854-862Article in journal (Refereed)
    Abstract [en]

    We propose a network architecture consisting of long-reach passive optical network-based access and a transparent optical core network. The end users are connected to the remote node or the local exchange (LE) through an optical distribution network, and the remote node is connected by disjoint feeder fiber links to central offices located in two distinct metro/ core (MC) nodes. This method of connecting a single remote node to two geographically separate MC nodes for dedicated protection in case of feeder fiber failure is referred to as dual homing. In this work, we explore the benefits of dual homing in the access in simultaneously providing better resilience and load balancing in the core network considering connections between LEs. While looking into the benefits of dual homing in terms of network resiliency, we also explore whether the path redundancies added by dual homing play a role in providing efficient distribution of load across the core network and thereby reduce the cost of provisioning capacity in terms of number of lightpaths, transponders, etc. Dual homing at both the source and destination LEs offers more options for paths between LEs through the core network. Our results show that dual-homed access proves to be advantageous over single-homed access in terms of enhancing both core network resiliency and facilitating better load balancing.

  • 177. Natalino, C.
    et al.
    Ahmed, J.
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Frances, R.
    A relocation-based heuristic for restoring optical cloud services2014In: 2014 13th International Conference on Optical Communications and Networks, 2014Conference paper (Refereed)
    Abstract [en]

    Optical clouds allow for an integrated management of optical transport and cloud resources (e.g., storage and computing resources running on datacenters). In this paradigm the concept of service relocation (i.e., the ability to re-allocate to a different datacenter node an already provisioned cloud service) offers a new way to restore the network upon failure. This paper presents a heuristic (called H-RELOCATION) based on the service relocation concept to be used for the dynamic restoration of optical cloud services. Upon the occurrence of a network failure, H-RELOCATION solves the routing and resource (i.e., transport plus cloud) allocation problem for each disrupted cloud service allowing, if necessary, to relocate some cloud services to different datacenter nodes. The proposed strategy is benchmarked against two optimal restoration strategies based on Integer Linear Programming (ILP) formulations, the first one without and the second one with the ability to use the service relocation idea. Simulation results show that H-RELOCATION offers performance (i.e., blocking probability, restorability levels and number of required relocations) very close to the optimum, offering on the other hand, a significant reduction in the processing time required for each successfully restored cloud service.

  • 178.
    Natalino, Carlos
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Chiaraviglio, L.
    Idzikowski, F.
    Francês, C. R. L.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Optimal lifetime-aware operation of green optical backbone networks2016In: IEEE Journal on Selected Areas in Communications, ISSN 0733-8716, E-ISSN 1558-0008, ISSN 0733-8716, Vol. 34, no 12, p. 3915-3926, article id 2611879Article in journal (Refereed)
    Abstract [en]

    This paper targets the lifetime-aware management of a set of optical line amplifiers (OLAs) in an optical network exploiting sleep mode (SM) in order to save energy. We first present a simple model to predict the OLA lifetime. We then provide different mixed-integer linear programming (MILP) formulations, which jointly consider energy saving and lifetime. The proposed MILP formulations are then solved on different realistic scenarios, by taking into account the spatial and temporal variations of traffic demands. Results show that our lifetime-aware approach outperforms classical energy saving ILP formulations, which instead tend to notably decrease the OLA lifetime. More important, the proposed approaches can achieve a good lifetime performance without consuming significantly more energy than purely energy-aware strategies.

  • 179.
    Natalino, Carlos
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Chiaraviglio, Luca
    Idzikowski, Filip
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Listani, Marco
    Carlos, Frances
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Lifetime-Aware Provisioning in Green Optical Backbone Networks2016In: 2016 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION (OFC), Optical Society of America, 2016Conference paper (Refereed)
    Abstract [en]

    We present a framework able to limit the device lifetime degradation in optical backbone networks using sleep-mode-based green strategies. Results show that our approach manages the lifetime while not compromising significantly the energy saving performance. 

  • 180.
    Natalino, Carlos
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Coelho, Frederico
    Fed Univ Minas Gerais UFMG, Belo Horizonte, MG, Brazil..
    Lacerda, Gustavo
    Fed Univ Minas Gerais UFMG, Belo Horizonte, MG, Brazil..
    Braga, Antonio
    Fed Univ Minas Gerais UFMG, Belo Horizonte, MG, Brazil..
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    A Proactive Restoration Strategy for Optical Cloud Networks Based on Failure Predictions2018In: 20th International Conference on Transparent Optical Networks, ICTON 2018 / [ed] Jaworski, M Marciniak, M, Institute of Electrical and Electronics Engineers (IEEE), 2018, article id 8473938Conference paper (Refereed)
    Abstract [en]

    Failure prediction based on the anomaly detection/forecasting is becoming a reality thanks to the introduction of machine learning techniques. The orchestration layer can leverage on this new feature to proactively reconfigure cloud services that might find themselves traversing an element that is about to fail. As a result, the number of cloud service interruptions can be reduced with beneficial effects in terms of cloud service availability. Based on the above intuition, this paper presents an orchestration strategy for optical cloud networks able to reconfigure vulnerable cloud services (i.e., the ones that would be disrupted if a predicted failure happens) before an actual failure takes place. Simulation results demonstrate that, with a single link failure scenario, proactive restoration can lead to up to 97% less cloud services having to be relocated. This result brings considerable benefits in terms of cloud service availability, especially in low load conditions. It is also shown that these improvements come with almost no increase in the cloud service blocking probability performance,i.e., resource efficiency is not impacted.

  • 181.
    Natalino, Carlos
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Idzikowski, F.
    Poznan Univ Tech, Fac Elect & Telecommun, Poznan, Poland.
    Chiaraviglio, L.
    Univ Roma Tor Vergata, EE Dept, Rome, Italy.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    EFAH: An energy and fatigue aware heuristic for provisioning highly available connections in optical backbone networks2017In: Proceedings of 2017 9th International Workshop on Resilient Networks Design and Modeling, RNDM 2017, Institute of Electrical and Electronics Engineers Inc. , 2017Conference paper (Refereed)
    Abstract [en]

    Optical backbone operators need to meet the availability requirements specified in the Service Level Agreements (SLAs). While less stringent availability constraints, i.e., less than three 9's might be met by provisioning connections without any protection, more stringent requirements, i.e., five 9's, force operator to use proactive protection strategies. The connection provisioning process becomes more cost-efficient when green aspects are considered. On the other hand, energy awareness introduces thermal fatigue effects, which may in turn lower the lifetime of devices that undergo frequent power state transitions, i.e., between Active Mode (AM) and Sleep Mode (SM). As a result the availability level experienced by the unprotected connections may decrease. At the same time, with devices failing more frequently the protection level chosen for a given connection might not be enough to guarantee the required average connection availability performance. This work tackles the problem of managing an optical back-bone network when green and thermal fatigue aspects are introduced. We propose an Energy and Fatigue Aware Heuristic (EFAH) that is able to balance between thermal fatigue effects and energy saving performance. When compared to the pure Energy-Aware (EA) strategies, EFAH manages to significantly improve the value of the average connection availability of both unprotected and protected connections. On the other hand, there is a price to pay in terms of lower energy saving performance.

  • 182.
    Natalino, Carlos
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Idzikowski, Filip
    Poznan Univ Tech, Fac Elect & Telecommun, Poznan, Poland..
    Chiaraviglio, Luca
    Univ Roma Tor Vergata, EE Dept, Rome, Italy..
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Energy- and fatigue-aware RWA in optical backbone networks2019In: Optical Switching and Networkning Journal, ISSN 1573-4277, E-ISSN 1872-9770, Vol. 31, p. 193-201Article in journal (Refereed)
    Abstract [en]

    Connection provisioning in Wavelength Division Multiplexing (WDM) networks needs to account for a number of crucial parameters. On the one hand, operators need to ensure the connection availability requirements defined in Service Level Agreements (SLAs). This is addressed by selecting an appropriate amount of backup resources and recovery strategies for the connections over which services are provisioned. Services requiring less strict availability requirements can be routed over unprotected lightpaths. Services with more strict availability requirements are provisioned over protected lightpaths in order to cope with possible failures in the network. Another important aspect to consider during the provisioning process is energy efficiency. Green strategies leverage on setting network devices in Sleep Mode (SM) or Active Mode (AM) depending on whether or not they are needed to accommodate traffic. However, frequent power state changes introduce thermal fatigue which in turn has a negative effect on the device lifetime. Finally, in multi-period traffic scenarios, it is also important to minimize the number of reconfigurations of lightpaths already established in the network in order to avoid possible traffic disruptions at higher layers. The work presented in this paper tackles the connection provisioning paradigm in an optical backbone network with a multi-period traffic scenario. More specifically the paper looks into the interplay among (i) energy efficiency, (ii) thermal fatigue, and (iii) lightpath reconfiguration aspects. To this end, the Energy and Fatigue Aware Heuristic with Unnecessary Reconfiguration Avoidance (EFAH-URA) is introduced, showing that it is possible to balance the three aspects mentioned above in an efficient way. When compared to the pure energy-aware strategies, EFAH-URA significantly improves the average connection availability for both unprotected and protected connections. On the other hand, it is done at the expense of reduced energy saving.

  • 183.
    Natalino, Carlos
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Franca, Luis
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Frances, Carlos R. L.
    Costa, Joao C. W. A.
    Dimensioning Optical Clouds with Shared-Path Shared-Computing (SPSC) Protection2015In: High Performance Switching and Routing (HPSR), 2015 IEEE 16th International Conference on, IEEE conference proceedings, 2015Conference paper (Refereed)
    Abstract [en]

    Service relocation represents a promising strategy to provide flexible and resource efficient resiliency from link failures in the optical cloud environment. However, when a failure affects a node hosting a datacenter (DC), service relocation from the affected DC is not possible. One alternative to protect against DC failures relies on using design strategies that duplicate the IT (i.e., storage and processing) resources in a backup DC at the expense of increasing resource overbuild (i.e., cost) of the network. This work proposes a dimensioning strategy based on the shared-path shared-computing (SPSC) concept able to protect against any single link, server, or DC failure scenario with minimal resource overbuild for the network and IT infrastructures. SPSC is based on the intuition that only storage units need complete replication in backup DC, while processing units can be instantiated only after the occurrence of a failure, leaving the design strategy some leeway to minimize their number. As result, the proposed SPSC design shows a considerable reduction in the amount of backup resources when compared to the dedicated protection strategies.

  • 184.
    Natalino, Carlos
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Raza, Muhammad Rehan
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    O¨hlen, P.
    Batista, P.
    Santos, M.
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Machine-learning-based routing of QoS-constrained connectivity services in optical transport networks2018In: Optics InfoBase Conference Papers, Optical Society of America, 2018Conference paper (Refereed)
    Abstract [en]

    Quality of Service (QoS) constraints are crucial in 5G networks. The paper presents a provisioning strategy for connectivity services with different priorities based on reinforcement learning able to accommodate QoS requirements while maximizing provider profits.

  • 185.
    Natalino, Carlos
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Raza, Muhammad Rehan
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Rostami, A.
    Deutsche Bahn AG, Germany.
    Ohlen, P.
    Ericsson Research, Kista, Sweden.
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Machine Learning Aided Orchestration in Multi-Tenant Networks2018In: IEEE Photonics Society Summer Topicals Meeting Series, SUM 2018, Institute of Electrical and Electronics Engineers Inc. , 2018, p. 125-126Conference paper (Refereed)
    Abstract [en]

    Software Defined Networking enables the efficient sharing of a network infrastructure among different tenants, a concept known as network slicing. The paper presents a slicing strategy based on reinforcement learning able to efficiently orchestrate services requested by mobile and cloud tenants. 

  • 186.
    Natalino, Carlos
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Schiano, M.
    Di Giglio, A.
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Furdek, Marija
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Field Demonstration of Machine-Learning-Aided Detection and Identification of Jamming Attacks in Optical Networks2018In: European Conference on Optical Communication, ECOC, Institute of Electrical and Electronics Engineers Inc. , 2018Conference paper (Refereed)
    Abstract [en]

    We develop a machine-learning-aided framework for detection and identification of optical network jamming signal attacks of varying intensities. Trained with data gathered in our field-deployed experimental setup, the approach achieves 93% accuracy on average over the considered attack scenarios.

  • 187.
    Natalino, Carlos
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Sousa, A. D.
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Furdek, Marija
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    On the trade-offs between user-to-replica distance and CDN robustness to link cut attacks2018In: Proceedings of 2018 10th International Workshop on Resilient Networks Design and Modeling, RNDM 2018, Institute of Electrical and Electronics Engineers Inc. , 2018Conference paper (Refereed)
    Abstract [en]

    Content Delivery Networks (CDNs) are a key enabler for geographically-distributed content delivery with high throughput and low latency. As CDNs utilize the underlying optical core network infrastructure, they inherit its vulnerability to targeted link cut attacks which can cause severe service degradation. One of the fundamental problems in CDN configuration is deciding on the placement of content replicas across the underlying network of data centers, which should obtain balance among multiple, often conflicting performance criteria. This paper investigates the implications of minimizing the average distance between the users and the content replicas on the CDN robustness to targeted link cuts.To this end, we compute Pareto-optimal replica placement solutions with minimal user-to-replica distance and maximal robustness to link cut attacks of the highest damaging potential. k-best replica placement solutions in terms of the user-to-replica distance are calculated by formulating the problem as an Integer Linear Programming (ILP) exact method. For each replica placement solution, the worst case link cut attack scenario is identified by defining the Critical Link Set Detection (CLSD) problem. CLSD returns the link set whose cutting disconnects the maximal number of nodes from the content. We develop an ILP model for the CLSD and evaluate the robustness of the resulting CDN attack scenario in terms of mean content accessibility. The approach is evaluated through extensive simulations on real-world reference topologies, indicating that it is possible to improve the robustness to link cuts at the expense of small user-to-replica distance penalties. Moreover, the improvement of robustness is more significant for topologies with smaller average node degree and when cuts involve a larger number of links.

  • 188.
    Natalino, Carlos
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Spadaro, Salvatore
    Costa, Joao
    Carlos, Frances
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Restoration in Optical Cloud Networks With Relocation and Services Differentiation2016In: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 8, no 2, p. 100-111Article in journal (Refereed)
    Abstract [en]

    Optical cloud networks allow for the integrated management of both optical and IT resources. In this paradigm, cloud services can be provisioned in an anycast fashion; i.e., only the source node asking for a service is specified, while it is up to the cloud control/management system to select the most suitable destination data center (DC) node. During the cloud service provisioning process, resiliency is crucial in order to guarantee continuous network operations also in the presence of failures. On the one hand, a survivability strategy needs to be able to meet the availability requirements of each specific cloud service, while on the other hand it must be efficient in using backup resources. This paper proposes a restoration-based survivability strategy, which combines the benefits of both cloud service relocation and service differentiation concepts. The former is used to enhance the restorability performance (i.e., the percentage of successfully restored cloud services) offered by restoration, while the latter ensures that critical services are given the proper consideration while backup resources are assigned. The paper proposes both an integer linear programming (ILP) formulation, which guarantees optimal results, and a heuristic, which trades the optimality of the solution achieved by the ILP for faster processing times. Simulation results show that the average service availability and restorability performance obtained by both the ILP and the heuristic are very close to that achievable using a protection-based strategy, but with the inherent benefit, in terms of efficient use of resources, offered by a restoration-based approach.

  • 189.
    Natalino, Carlos
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Yayimli, Aysegul
    Valparaiso Univ, Comp & Informat Sci Dept, Indiana, PA USA..
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Furdek, Marija
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Infrastructure upgrade framework for Content Delivery Networks robust to targeted attacks2019In: Optical Switching and Networkning Journal, ISSN 1573-4277, E-ISSN 1872-9770, Vol. 31, p. 202-210Article in journal (Refereed)
    Abstract [en]

    Content Delivery Networks (CDNs) are crucial for enabling delivery of services that require high capacity and low latency, primarily through geographically-diverse content replication. Optical networks are the only available future-proof technology that meets the reach and capacity requirements of CDNs. However, the underlying physical network infrastructure is vulnerable to various security threats, and the increasing importance of CDNs in supporting vital services intensifies the concerns related to their robustness. Malicious attackers can target critical network elements, thus severely degrading network connectivity and causing large-scale service disruptions. One way in which network operators and cloud computing providers can increase the robustness against malicious attacks is by changing the topological properties of the network through infrastructure upgrades. This work proposes a framework for CDN infrastructure upgrade that performs sparse link and replica addition with the objective of maximizing the content accessibility under targeted link cut attacks. The framework is based on a newly defined content accessibility metric denoted as mu-ACA which allows the network operator to gauge the CDN robustness over a range of attacks with varying intensity. Two heuristics, namely Content-Accessibility Aware Link Addition Heuristic (CAA-LAH), and Content-Accessibility-Aware Replica Addition Heuristic (CAA-RAH) are developed to perform strategic link and replica placement, respectively, and hamper attackers from disconnecting users from the content even in severe attack scenarios. Extensive experiments on real-world reference network topologies show that the proposed framework effectively increases the CDN robustness by adding a few links or replicas to the network.

  • 190.
    Natalino, Carlos
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Yayimli, Aysegul
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Link Addition Framework for Optical CDNs Robust to Targeted Link Cut Attacks2017In: PROCEEDINGS OF 2017 9TH INTERNATIONAL WORKSHOP ON RESILIENT NETWORKS DESIGN AND MODELING (RNDM) / [ed] Rak, J; Bilo, D; Marzo, J; Calle, E; Pareta, JS, IEEE conference proceedings, 2017Conference paper (Other academic)
    Abstract [en]

    Content Delivery Networks (CDNs) are a key enabler for the distribution of large amounts of data with high capacity and low latency. For instance, content streaming companies extensively use geographical distribution and replication to meet the ever-growing demand for media. Optical networks are the only future-proof technology available that meets the reach and capacity requirements of CDNs. However, the robustness of optical networks becomes a point of concern, as they can be a target of deliberate link cuts that can severely degrade network connectivity and cause large-scale service disruption. To mitigate the vulnerabilities, actions can be taken in the optical and/or cloud infrastructures. The replication of content across geographically diverse data centers results in an intrinsic increase of content accessibility. At the network infrastructure level, robustness to attacks can be enhanced by increasing the topology connectivity through link addition. This work focuses on the latter approach and its effectiveness in increasing content accessibility in the presence of deliberate link cuts. The paper proposes a framework for evaluation and enhancement of content accessibility in CDNs by sparse link addition. First, a content accessibility measure called mu-ACA is introduced to gauge the content accessibility of a given network topology under a set of link cut attack scenarios. Based on this measure, a new link addition strategy is defined aimed at maximizing the content accessibility for a given number of extra links. Simulation results on real-world reference topologies show that the proposed strategy can significantly improve content accessibility by adding a very limited number of optical fiber links.

  • 191. Nooruzzaman, Md
    et al.
    Alloune, Nabih
    Nabet, Feriel
    Archambault, Emile
    Tremblay, Christine
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Littlewood, Paul
    Bélanger, Michel
    Agile filterless submarine networks2016Conference paper (Refereed)
  • 192. Nooruzzaman, Md.
    et al.
    Alloune, Nabih
    Nabet, Feriel
    Xu, Zhenyu
    Archambault, Emile
    Tremblay, Christine
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Littlewood, Paul
    Belanger, Michel P.
    Filterless Architecture for Coherent Undersea Networks2015In: 2015 INTERNATIONAL CONFERENCE ON OPTICAL NETWORK DESIGN AND MODELING (ONDM), IEEE , 2015, p. 68-73Conference paper (Refereed)
    Abstract [en]

    Active photonic switching components, such as reconfigurable optical add/drop multiplexers (ROADMs), cannot be deployed at the branching units (BUs) in submarine networks, which limits the flexibility of the undersea networks. In this regard, the filterless optical network architecture based on passive broadcast-and-select nodes and coherent transceivers at the edge terminals can be considered as a promising solution. In this paper we propose and evaluate a filterless network architecture for a trunk and branch undersea network topology. The performance is compared with a conventional solution in terms of cost and wavelength consumption. And it is shown that the filterless architecture can bring significant cost savings for both the terminals and line equipment while offering the same agility as the conventional network architecture.

  • 193. Ohlen, P.
    et al.
    Skubic, B.
    Rostami, A.
    Ghebretensae, Z.
    Martensson, J.
    Wang, K.
    Fiorani, Matteo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Data plane and control architectures for 5G transport networks2015In: European Conference on Optical Communication, ECOC, Institute of Electrical and Electronics Engineers (IEEE), 2015Conference paper (Refereed)
    Abstract [en]

    Next generation 5G mobile system will support the vision of connecting all devices that benefit from a connection. Transport networks need to support the required capacity, latency and flexibility. This paper outlines how 5G transport networks will address these requirements.

  • 194. O'Mahony, M.
    et al.
    Politi, C.T.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Tzanakaki, Anna
    Mitchell, J.
    Van Daele, P.
    Key Technologies for Optical Networks2009In: International Commission for Optics: topical meeting on Emerging Trends and Novel Materials in Photonics (ICO-PHOTONICS-DELPHI2009), 2009Conference paper (Refereed)
  • 195. Palkopoulou, E.
    et al.
    Meusburger, C.
    Schupke, D.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Photonics (Closed 20120101).
    Bauschert, T.
    Combining multi-period and multi-layer network planning: Ignored potential?2010In: 36th European Conference and Exhibition on Optical Communication, ECOC 2010, 2010Conference paper (Refereed)
    Abstract [en]

    Multi-layer and multi-period network planning can lead to significant cost reductions. Using linear programming we study the effect of their joint consideration for IP-over-WDM networks. Case studies show cost savings surpassing 20% by including forecast knowledge in multi-layer optimization.

  • 196. Pandi, Z.
    et al.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    On temporary inconsistency of the link state database with prompt update policies2005In: 2005 7th International Conference on Transparent Optical Networks, Vol 1, Proceedings, 2005, Vol. 1, p. 437-440Conference paper (Refereed)
    Abstract [en]

    Link state databases maintained in parallel at each node in networks that require link state information for proper operation try to reflect real-time changes of the network state. Information dissemination, however, by its very nature introduces latency in the update of link state information at different nodes, which may in turn lead to faulty decisions that entail additional delay perceived by user traffic. The paper presents a probabilistic model based on simple assumptions in order to derive an upper bound on the probability that such a link state database inconsistency occurs.

  • 197. Pandi, Zsolt
    et al.
    Tacca, Marco
    Fumagalli, Andrea
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics.
    Dynamic provisioning of availability-constrained optical circuits in the presence of optical node failures2006In: Journal of Lightwave Technology, ISSN 0733-8724, E-ISSN 1558-2213, Vol. 24, no 9, p. 3268-3279Article in journal (Refereed)
    Abstract [en]

    This paper investigates what impact optical node failures may have on wavelength-division-multiplexed networks, in which reliable end-to-end optical circuits are provisioned dynamically. At the node level, the optical cross-connect (OXC) equipment availability measure is estimated using proven component level availability models. At the network level, end-to-end optical circuits are provisioned only when the level of connection availability required by the application can be guaranteed. With the objective of yielding efficient utilization of the network resources, i.e., fibers and OXCs, circuit redundancy is achieved by means of shared path protection (SPP) switching, in combination with. differentiated reliability (DiR). The resulting optimal routing and wavelength assignment problem is proven to be NP-complete. To produce suboptimal solutions in polynomial time, a heuristic technique is presented, which makes use of a time-efficient method to estimate the end-to-end circuit availability in the presence of multiple (link and node) failures. Using the proposed heuristic, a selection of representative OXC architectures and optical switching technologies is examined to assess the influence of the node equipment choice on the overall network performance.

  • 198. Pederzolli, F.
    et al.
    Furdek, Marija
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Siracusa, D.
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Towards secure optical networks: A framework to aid localization of harmful connections2018In: Optics InfoBase Conference Papers, Optics Info Base, Optical Society of America, 2018Conference paper (Refereed)
    Abstract [en]

    We model the scope of optical signal insertion attacks by defining attack syndromes for each connection, and present a cost-efficient routing heuristic that aids localization of harmful connections by reducing syndrome ambiguity in the network.

  • 199.
    Pederzolli, Federico
    et al.
    FBK CREATE NET, Via Cascata 56-D Povo, Trento, Italy..
    Furdek, Marija
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Siracusa, Domenico
    FBK CREATE NET, Via Cascata 56-D Povo, Trento, Italy..
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Towards Secure Optical Networks: A Framework to Aid Localization of Harmful Connections2018In: 2018 Optical Fiber Communications Conference and Exposition, OFC 2018 - Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2018Conference paper (Refereed)
    Abstract [en]

    We model the scope of optical signal insertion attacks by defining attack syndromes for each connection, and present a cost-efficient routing heuristic that aids localization of harmful connections by reducing syndrome ambiguity in the network.

  • 200.
    Peroza Marval, Maria Jose
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Fumagalli, A.
    Adaptive routing based on summary information mitigates the adverse impact of outdated control messages2011In: Transparent Optical Networks (ICTON), 2011 13th International Conference on, Stockholm, 2011, p. 1-4Conference paper (Refereed)
    Abstract [en]

    Adaptive routing is considered as a promising solution to support flexible resource allocation in wavelength division multiplexing network. Resource advertisement protocols, such as link state advertisement (LSA), are essential to enable routing algorithms to efficiently carry out the required path computation. The LSA nonnegligible convergence time may lead to outdated link information, which in turns may adversely affect the efficiency of the computed path. As a result, traffic engineering is suboptimal and some services may be unnecessarily blocked. This study investigates the impact of outdated information on the blocking probability of adaptive routing schemes focusing on two LSA protocols: one advertising specific resource information and one advertising only a summary of the same. Our simulation results show that compared with the routing scheme requiring specific information LSA, the approach based on LSA with summary information is by its nature not precise and hence able to mitigate the adverse impact of the LSA convergence time on blocking performance.

1234567 151 - 200 of 337
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