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  • 301.
    Wosinska, Lena
    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).
    Fiorani, Matteo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Dreier, Dennis
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    ICT Infrastructure for Smart Cities: Curitiba, Brazil2015Conference paper (Other academic)
  • 302.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Simeonidou, Dimitra
    Tzanakaki, Anna
    Raffaelli, Carla
    Politi, Christina
    Optical Networks for the Future Internet: Introduction [to the Special Issue]2009In: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 1, no 2, p. FI1-FI3Article in journal (Refereed)
    Abstract [en]

    Not available

  • 303.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Simeonidou, Dimitra
    Tzanakaki, Anna
    Raffaelli, Carla
    Politi, Christina (Tanya)
    Optical Networks for the Future Internet2008In: Journal of Optical Networking, ISSN 1536-5379, Vol. 7, no 5, p. v-viArticle in journal (Refereed)
  • 304.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics.
    Svensson, Torbjorn K.
    Analysis of connection availability in an all-optical mesh network2007In: Fiber and integrated optics (Print), ISSN 0146-8030, E-ISSN 1096-4681, Vol. 26, no 2, p. 99-110Article in journal (Refereed)
    Abstract [en]

    This paper presents the method of an availability performance analysis that can be used for all-optical networks. We compare different schemes of protection and restoration in a full), connected mesh network based on optical cross-connects, optical fibers, and fiber amplifiers. Specifically treated is all optical mesh network physically mapped onto a Scandinavian backbone. In order to compare different survivability strategies, we selected two nodes located roughly 420 km apart. The goal of this work is to point out possible ways to improve connection availability. A number of survivability schemes are compared, for which the availability model of logical connection is derived and a calculation procedure is described. Our results show that unprotected schemes cannot ascertain reasonably high requirements on connection availability in the backbone network. Thus, if a redundant structure of logical connection is considered, the particular survivability scheme should be evaluated in order to maximize connection availability.

  • 305.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Tacca, Marco
    Fumagalli, Andrea
    Autenrieth, Achim
    Reliability Issues in Optical Networking2007In: Journal of Optical Networking, ISSN 1536-5379, Vol. 6, no 10, p. i-iiArticle in journal (Refereed)
  • 306.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT). Royal Inst Technol KTH ICT, Stockholm, Sweden..
    Tacca, Marco
    Univ Texas Dallas, Dallas, TX 75230 USA..
    Fumagalli, Andrea
    Univ Texas Dallas, Dallas, TX 75230 USA..
    Autenrieth, Achim
    Reliability Issues in Optical Networks: introduction to the feature issue2008In: Journal of Optical Networking, ISSN 1536-5379, Vol. 7, no 10, p. 834-836Article in journal (Other academic)
  • 307.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Thylen, Lars
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Reliability analysis of an optical ATM switch based on wavelength routing1997In: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 9, p. 336-338Article in journal (Refereed)
    Abstract [en]

    Reliability studies of a demonstrated asynchronous transfer mode (ATM) switch with all-optical packet routing are presented. Calculations are based on available reliability data for commercial components. An additional inherent redundancy is shown to improve switch availability. Our calculation results further show that a proposed multiplane switch satisfies the general reliability requirement for switching systems.

  • 308.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Thylen, Lars
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Reliability performances of optical ATM switches based on different routing and buffering schemes1999In: IEEE Transactions on Communications, ISSN 0090-6778, E-ISSN 1558-0857, Vol. 47, p. 472-475Article in journal (Refereed)
    Abstract [en]

    Reliability performances of seven equal-capacity optical asynchronous transfer mode switches based on different routing and buffering schemes are compared. Calculations are based on available reliability data for commercial components as well as expected life lengths for new components and systems. In general, for switching systems, the average downtime is required to be held below 3 min/year. However, our results indicate that the average downtime for the proposed configurations is much longer than requested, over ten times longer for the best case and over 1500 times longer for the worst case. Therefore, the multiplane structures (i.e., multiplying of the entire systems) have to be provided for the switching systems investigated here in order to satisfy reliability requirements

  • 309.
    Wosinska, Lena
    et al.
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Thylén, Lars
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Holmstrom, R. P.
    Large-capacity strictly nonblocking optical cross-connects based on microelectrooptomechanical systems (MEOMS) switch matrices: Reliability performance analysis2001In: Journal of Lightwave Technology, ISSN 0733-8724, E-ISSN 1558-2213, Vol. 19, no 8, p. 1065-1075Article in journal (Refereed)
    Abstract [en]

    In this paper, the reliability performance of 128 x 128 optical cross-connects (OXCs) based on microelectrooptomechanical systems (MEOMS) switch matrices is considered. First, we compare a strictly nonblocking wavelength selective switch with a strictly nonblocking three-stage Clos architecture. The probability of maintenance of free operation has been investigated for both OXC structures. We present our calculation results for such commonly used reliability measures as mean time between failures (MTBF), mean downtime (MDT) per year, and steady-state unavailability. It is shown that the reliability performances of the considered OXCs are far from that requested. In this paper, we also investigate possibilities of improving the reliability performance of the considered OXCs by introducing shared redundancy of the MEOMS matrices. We propose two different protection schemes: one for the wavelength selective switch [1] and another for the three-stage Clos architecture. It is shown that the proposed protection schemes significantly improve the reliability performance for both cases. Finally, we compare the performance of the all-optical version of the OXC based on MEOMS matrices with the optoelectronic version of the OXC based on electronic cross-point switch matrices. It is shown that from a reliability viewpoint, the optical cross-connect based on MEOMS matrices is better than that with electrical cross-point switches. The influence of capacity expansion on the system reliability is discussed.

  • 310.
    Wosinska, Lena
    et al.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Thylén, Lars
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics.
    Öberg, Johnny
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Buffering and control in an all-optical packet switching node2005In: 2005 7th International Conference on Transparent Optical Networks, Vol 1, Proceedings, 2005, p. 205-211Conference paper (Refereed)
    Abstract [en]

    In this paper we study novel types of optical memories in context of their usefulness for optical buffering applications. We describe a new type of photonic packet switch with electrical shared buffering and show that the employment of a few optical buffer positions to complement the electronic ones significantly improves the switch performance. Different admission algorithms are applied in order to provide quality of service support. Furthermore, we propose two designs for the node control block.

  • 311.
    Wosinski, Lech
    et al.
    KTH, School of Information and Communication Technology (ICT).
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT).
    Si-basedmonolithically integrated triplexer transceiver for FTTH applications2012Conference paper (Refereed)
    Abstract [en]

    In this paper we present a Si-based monolithically integrated triplexer transceiver along with some applications in Passive Optical Networks (PONs). The device can be used to provide an additional channel for TV distribution where three wavelengths are assigned according to ITU G. 983 standard, 1310 nm for upstream voice and data, 1490 nm for downstream voice and data, and 1550 nm for downstream TV distribution, respectively. Moreover, the device can be utilized for PON monitoring by its inherent ability to terminate the supervision channels, e.g. U-band wavelengths (1625-1675 nm).  In this way, no extra component is required at the Optical Network Unit (ONU) to filter the monitoring wavelengths and hence no added insertion loss is introduced.  Furthermore, when using monitoring technique based on Optical Time-Domain Reflectometry (OTDR), the Rayleigh backscattered and discretely reflected radiation can be detected without additional noise coming from the ONU.

  • 312. Wu, Jing
    et al.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Jin, Yaohui
    Araki, Soichiro
    Guest editorial2013In: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 54, no 2, p. 111-112Article in journal (Refereed)
  • 313. Wu, Jing
    et al.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Jin, Yaohui
    Araki, Soichiro
    Special Issue on Optical Network Architectures and Management2011In: Optical Switching and Networkning Journal, ISSN 1573-4277, E-ISSN 1872-9770, Vol. 8, no 4, p. 225-225Article in journal (Other academic)
  • 314. Wu, Jing
    et al.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Machuca, Carmen Mas
    Tzanakaki, Anna
    Hasegawa, Hiroshi
    Untitled2014In: Optical Switching and Networkning Journal, ISSN 1573-4277, E-ISSN 1872-9770, Vol. 11, p. 53-54Article in journal (Refereed)
  • 315. Wu, Jing
    et al.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Shen, Gangxiang
    Spadaro, Salvatore
    Advances in optical networks control and management2013In: Optical Switching and Networkning Journal, ISSN 1573-4277, E-ISSN 1872-9770, Vol. 10, no 1, p. 1-2Article in journal (Other academic)
  • 316. Wu, Jing
    et al.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Shen, Gangxiang
    Spadaro, Salvatore
    Optical Networks Control and Management2014In: Journal of Network and Systems Management, ISSN 1064-7570, E-ISSN 1573-7705, Vol. 22, no 3, p. 434-436Article in journal (Refereed)
  • 317. Wu, Jing
    et al.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Tzanakaki, Anna
    Shen, Gangxiang
    Forward of special issue on "Optical Network Architectures, Systems and Applications"2015In: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 60, no 3, p. 347-347Article in journal (Other academic)
  • 318. Xu, Z.
    et al.
    Archambault, E.
    Tremblay, C.
    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).
    Belanger, M. P.
    Littlewood, P.
    1+1 dedicated optical-layer protection strategy for filterless optical networks2014In: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 18, no 1, p. 98-101Article in journal (Refereed)
    Abstract [en]

    We propose a dedicated optical-layer protection strategy for filterless optical networks offering a 100% protection ratio by introducing a limited number of wavelength selective components at selected intermediate nodes. A comparison with conventional active photonic switching networks is presented. The results show that the proposed 1+1 protection for filterless networks exhibits a clear cost advantage at similar wavelength usage compared to active switching solutions.

  • 319. Xu, Zhenyu
    et al.
    Tremblay, Christine
    Archambault, Emile
    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).
    Belanger, Michel P.
    Littlewood, Paul
    Flexible Bandwidth Allocation in Filterless Optical Networks2015In: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 19, no 4, p. 565-568Article in journal (Refereed)
    Abstract [en]

    We introduce the new concept of an elastic filterless optical network and propose an efficient heuristic algorithm for solving the static routing and spectrum assignment problem. Our simulation results obtained for different network topologies under multi-period traffic show increasing bandwidth savings with the growth of traffic load compared to a fixed-grid scenario. We also show the benefits of periodical spectrum defragmentation.

  • 320.
    Yaghoubi, Forough
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Electrical Engineering and Computer Science (EECS).
    Chen, Jiajia
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Rostami, Ahmad
    Corporate Research, Robert Bosch GmbH, Germany.
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Mitigation of Rain Impact on Microwave Backhaul Networks2016In: Workshop on Next Generation Backhaul/Fronthaul Networks, 2016, p. 134-139Conference paper (Refereed)
    Abstract [en]

    Microwave backhaul networks are a cost-efficient option to support increasing capacity demands of mobile networks. However, inherent vulnerability of wireless backhauling to random fluctuations of the wireless channel complicates the design of reliable backhaul links. Long-lasting channel fluctuations such as rain fading may bring significant network performance degradation, and therefore, need to be carefully treated. This paper proposes a novel rain detection algorithm utilizing both temporal and spatial correlation of link status, aiming at efficiently distinguishing between long-term and shortterm channel fading. With this distinction, a central controller decides whether network-wide strategies, such as rerouting, are required to mitigate the effects of rain. The accuracy of the proposed detection method is evaluated by measuring false alarm and misdetection probabilities. Numerical results show high rain detection accuracy of the proposed algorithm. Consequently, the impact of imperfect rain detection on the network throughput performance and on the overhead imposed to the central controller becomes negligible.

  • 321.
    Yaghoubi, Forough
    et al.
    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).
    Rostami, Ahmad
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Mitigation of Rain Impact on Microwave Backhaul Networks2016In: 2016 IEEE International Conference on Communications Workshops (ICC), Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 134-139Conference paper (Refereed)
    Abstract [en]

    Microwave backhaul networks are a cost-efficient option to support increasing capacity demands of mobile networks. However, inherent vulnerability of wireless backhauling to random fluctuations of the wireless channel complicates the design of reliable backhaul links. Long-lasting channel fluctuations such as rain fading may bring significant network performance degradation, and therefore, need to be carefully treated. This paper proposes a novel rain detection algorithm utilizing both temporal and spatial correlation of link status, aiming at efficiently distinguishing between long-term and short-term channel fading. With this distinction, a central controller decides whether network-wide strategies, such as rerouting, are required to mitigate the effects of rain. The accuracy of the proposed detection method is evaluated by measuring false alarm and misdetection probabilities. Numerical results show high rain detection accuracy of the proposed algorithm. Consequently, the impact of imperfect rain detection on the network throughput performance and on the overhead imposed to the central controller becomes negligible.

  • 322.
    Yaghoubi, Forough
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Furdek, Marija
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Rostami, A.
    Öhlén, P.
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Reliable topology design of wireless networks under correlated failures2018In: 2018 IEEE International Conference on Communications (ICC), Institute of Electrical and Electronics Engineers (IEEE), 2018, article id 8422496Conference paper (Refereed)
    Abstract [en]

    Inherent vulnerability of wireless backhauling to random fluctuations of the wireless channel complicates the design of reliable backhaul networks. In the presence of such disturbances, network reliability can be improved by providing redundant paths between given source and destination. Many studies deal with modifying and designing the network topology to meet the reliability requirements in a cost- efficient manner. However, these studies ignore the correlation among link failures, such as those caused by rain. Consequently, the resulting topology design solutions may fail to satisfy the network reliability requirements under correlated failure scenarios. To address this issue, this paper studies the design of reliable wireless backhaul networks under correlated failures with focus on rain fading. We consider green-field topology design and brown-field topology upgrade scenarios with the objective to minimize the total cost of wireless links added to meet the target reliability requirement in the presence of correlated link failures. We propose a new model to formulate the spatial correlation using pairwise joint probability distribution of rain attenuation between different links. This model is applied to consider the link- wise correlation along individual paths, as well as the correlation among the multiple redundant paths from the source to the destination node of a traffic flow. We formulate the problem as a quadratic integer program, which is NP-hard, and develop a heuristic algorithm to find near-optimal solutions. Performance evaluation shows that correlation-aware design improves the resiliency under rain disturbance at a slightly increased cost.

  • 323.
    Yaghoubi, Forough
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Furdek, Marija
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Rostami, Ahmad
    Ericsson Res, Networks Orchestrat & Automat, S-16483 Kista, Sweden..
    Ohlen, Peter
    Ericsson Res, S-16483 Kista, Sweden..
    Wosinska, Lena
    KTH, School of Industrial Engineering and Management (ITM), Learning.
    Consistency-Aware Weather Disruption-Tolerant Routing in SDN-Based Wireless Mesh Networks2018In: IEEE Transactions on Network and Service Management, ISSN 1932-4537, E-ISSN 1932-4537, Vol. 15, no 2, p. 582-595Article in journal (Refereed)
    Abstract [en]

    Wireless network solutions, a dominant enabling technology for the backhaul segment, are susceptible to weather disturbances that can substantially degrade network throughput and/or delay, compromising the stringent 5G requirements. These effects can be alleviated by centralized rerouting realized by software defined networking architecture. However, careless frequent reconfigurations can lead to inconsistencies in the network states due to asynchrony between different switches, which can create congestion and limit the rerouting gain. The aim of this paper is to minimize the total data loss during rain disturbance by proposing an algorithm that decides on the timing, the sequence, and the paths for rerouting of network flows considering the imposed congestion during reconfiguration. At each time sample, the central controller decides whether to adopt the optimal routes at a switching cost, defined as the imposed congestion, or to keep using existing, sub-optimal routes at a throughput loss. To find optimal solutions with minimal data loss in a static scenario, we formulate a dynamic programming problem that utilizes perfect knowledge of rain attenuation for the whole rain period. For dynamic scenarios with unknown future rain attenuation, we propose an online consistency-aware rerouting algorithm, called consistency-aware rerouting with prediction (CARP), which uses the temporal correlation of rain fading to estimate future rain attenuation. Simulation results on synthetic and real networks validate the efficiency of our CARP algorithm, substantially reducing data loss and increasing network throughput with a fewer number of rerouting actions compared to a greedy and a regular rerouting benchmarking approaches.

  • 324.
    Yaghoubi, Forough
    et al.
    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).
    Rostami, Ahmad
    Ericsson AB.
    Öhlén, Peter
    Ericsson AB.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Consistency-aware Weather Disruption-tolerant Routing in SDNbased Wireless Mesh Networks2017In: IEEE TNSM Special Issue on Advances in Management of Softwarized NetworksArticle in journal (Other academic)
    Abstract [en]

    Although, wireless solutions continue to be a dominant enabling technology in the future backhaul  segment, they are susceptible to weather disturbances that may substantially degrade network throughput, or delay, compromising the 5G requirements.  These  effects  can  be  alleviated  by centralized rerouting realized by software defined networking (SDN) architecture. However, careless frequent reconfigurations may lead to inconsistencies in network states due to asynchrony between different switches, which may create  congestion and limit the gain of frequent rerouting.  In  this  paper, we focus on the rerouting process during rain disturbance considering the minimum total congestion imposed  during  the  update  of  routing  tables as a switching cost. At each time sample, the central controller has the possibility to adopt the optimal routes at a switching cost or to keep using previous routes at the expense of a throughput loss due to route sub- optimality. To find optimal solutions with minimal data loss in a static scenario, we formulate a dynamic programming problem that utilizes perfect knowledge of the rain attenuation for the whole rain period (off-line policy with full knowledge). For dynamic scenarios where the future rain attenuation data cannot be known, we propose an online consistency-aware rerouting algorithm, called optimal control action with prediction (OCAP), which uses the temporal correlation of rain fading to estimate the future rain attenuation. Simulation results on synthetic and real networks validate the efficiency of our OCAP algorithm, substantially reducing congestion and increasing network throughput with a fewer number of rerouting actions compared to benchmarks approaches.

  • 325.
    Yaghoubi, Forough
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Mahloo, Mozghan
    Ericsson AB.
    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).
    Farias, Fabricio de Souza
    Universidade Federal do Pará.
    Costa, João Crisóstomo Weyl Albuquerque
    Universidade Federal do Pará.
    A Techno-Economic Framework for 5G Transport Networks2017In: Article in journal (Other academic)
    Abstract [en]

    Wireless heterogeneous networks (HetNets) are a cost- and an energy-efficient alternative to provide high capacity to end users in the future 5G communication systems. However, the transport segment of a radio access network (RAN) poses a big challenge in terms of cost and energy consumption. In fact, if not planned properly its resulting high cost might limit the benefits of using small cells and impact the revenues of mobile network operators. Therefore, it is essential to be able to properly assess the economic viability of different transport techonolgies as well as their impact on the cost and profitability of a HetNets deployment (i.e., RAN + transport).

    This paper first presents a general and comprehensive techno-economic framework able to assess not only the total cost of ownership (TCO) but also the business viability of a HetNets deployment. It then applies it to the specific case study of a backhaul-based transport segment. In the evaluation work two technology options for the transport network are considered (i.e., microwave and fiber) assuming both a homogeneous (i.e., macro cells only) and a HetNet deployments. Our results demonstrate the importance of selecting the right technology and deployment strategy in order not to impact the economic benefits of a HetNet deployment. Moreover, the results also reveal that a deployment solution with the lowest TCO does not always lead to the highest profit.  

  • 326.
    Yaghoubi, Forough
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Mahloo, Mozhgan
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    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).
    Farias, Fabricio de Souza
    Fed Univ Para, Inst Technol, Belem, Para, Brazil..
    Weyl Albuquerque Costa, Joao Crisstomo
    Fed Univ Para, Inst Technol, Belem, Para, Brazil..
    Chen, Jiajia
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    A techno-economic framework for 5G transport networks2018In: IEEE wireless communications, ISSN 1536-1284, E-ISSN 1558-0687, Vol. 25, no 5, p. 56-63Article in journal (Refereed)
    Abstract [en]

    Wireless heterogeneous networks (HetNets) are a cost- and energy-efficient alternative to provide high capacity to end users in the future 5G communication systems. However, the transport segment of a RAN poses a big challenge in terms of cost and energy consumption. In fact, if not planned properly, its resulting high cost might limit the benefits of using small cells and impact the revenues of mobile network operators. Therefore, it is essential to be able to properly assess the economic viability of different transport technologies as well as their impact on the cost and profitability of a HetNet deployment (i.e., RAN plus transport). This article first presents a general and comprehensive techno-economic framework able to assess not only the TCO but also the business viability of a HetNet deployment. The framework is then applied to the specific case study of a backhaul-based transport segment. In the evaluation work two technology options for the transport network are considered (i.e., microwave and fiber) assuming both a homogeneous (i.e., macrocells only) and a HetNet deployment. Our results demonstrate the importance of selecting the right technology and deployment strategy in order not to impact the economic benefits of a HetNet deployment. Moreover, the results also reveal that a deployment solution with the lowest TCO does not always lead to the highest profit.

  • 327.
    Yaghoubi, Forough
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Rostami, Ahmad
    Ericsson AB.
    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).
    Öhlén, Peter
    Ericsson AB.
    Mitigation of rain impact on microwave networks2016Patent (Other (popular science, discussion, etc.))
  • 328. Yan, L.
    et al.
    Fiorani, Matteo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Muhammad, Ajmal
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Tornatore, M.
    Agrell, E.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Network performance trade-off in optical spatial division multiplexing data centers2017In: 2017 Optical Fiber Communications Conference and Exhibition, OFC 2017 - Proceedings, Institute of Electrical and Electronics Engineers Inc. , 2017Conference paper (Refereed)
    Abstract [en]

    We propose close-to-optimal network resource allocation algorithms for modular data centers using optical spatial division multiplexing. A trade-off between the number of established connections and throughput is identified and quantified.

  • 329.
    Yan, Li
    et al.
    Chalmers Univ Technol, Gothenburg, Sweden..
    Fiorani, Matteo
    KTH, School of Information and Communication Technology (ICT).
    Muhammad, Ajmal
    KTH, School of Information and Communication Technology (ICT).
    Tornatore, Massimo
    Politecn Milan, Milan, Italy..
    Agrell, Erik
    Chalmers Univ Technol, Gothenburg, Sweden..
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Network Performance Trade-Off in Modular Data Centers With Optical Spatial Division Multiplexing2018In: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 10, no 9, p. 796-808Article in journal (Refereed)
    Abstract [en]

    Modular design based on spatial division-multiplexing switches is a promising way to improve the capacity and reduce the cabling complexity of data center networks. However, due to the coexistence of mice and elephant flows, in modular data center networks a trade-off between the blocking probability and total throughput arises. In fact, blocking elephant flows would lead to a relevant penalty on the throughput but a small penalty on the blocking probability. In this paper, we investigate the relation between the blocking and throughput in modular data center networks based on optical spatial division multiplexing. We combine the two metrics linearly by a weight factor that prioritizes them relatively. To solve the resource allocation problem, we propose both mixed integer linear programming formulations and close-to-optimal heuristics for three different spatial division multiplexing switching schemes. Simulation results demonstrate that a carefully chosen weight factor is necessary to achieve a proper balance between the blocking probability and throughput for all the schemes.

  • 330. Yan, Li
    et al.
    Fiorani, Matteo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Muhammad, Ajmal
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Tornatore, Massimo
    Agrell, Erik
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Network Performance Trade-Off in Optical Spatial Division Multiplexing Data Centers2017In: 2017 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION (OFC), IEEE , 2017Conference paper (Refereed)
    Abstract [en]

    We propose close-to-optimal network resource allocation algorithms for modular data centers using optical spatial division multiplexing. A trade-off between the number of established connections and throughput is identified and quantified.

  • 331.
    Yang, Yanpeng
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Sung, Ki Won
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). 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).
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Hybrid Fiber and Microwave Protection for Mobile Backhauling2014In: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 6, no 10, p. 869-878Article in journal (Refereed)
    Abstract [en]

    Several studies have shown that optical-fiber-based backhauling offers a future proof solution to handle rapidly increasing traffic in wireless access networks and outperforms other existing backhauling technologies, such as microwave and copper, in terms of capacity, scalability, and sustainability. However, the deployment cost of fiber infrastructure is relatively high and it may be difficult to provide a cost efficient and flexible protection strategy for a fiber backhauling network. Considering that protection is very important to avoid service interruption in a high-capacity mobile backhauling network, in this paper we propose a hybrid fiber and microwave protection scheme for mobile backhauling based on a passive optical network (PON). The proposed reliable architecture is compatible with any wavelength division multiplexing (WDM)based PON, e. g., pure WDM PON and a hybrid time and wavelength division multiplexing (TWDM) PON, offering high flexibility and relatively low deployment cost. The backup for the feeder fiber is provided by dual homing, while the protection of the distribution section can be established via a microwave connection between two base stations in case high reliability performance is required, e. g., for macrocells covering large service areas. We have carried out an extensive assessment of our approach in terms of connection availability, failure impact, complexity, and flexibility in providing resiliency. We also show a comparison with other existing solutions. The evaluation results confirm that our scheme can achieve relatively high flexibility and reliability performance while maintaining low complexity compared with the existing approaches.

  • 332. Yuan, H.
    et al.
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT).
    Muhammad, Ajmal
    KTH, School of Information and Communication Technology (ICT).
    Saljoghei, A.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT).
    Zervas, G.
    Space-division multiplexing in data center networks: On multi-core fiber solutions and crosstalk-suppressed resource allocation2018In: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 10, no 4, p. 272-288Article in journal (Refereed)
    Abstract [en]

    The rapid growth of traffic inside data centers caused by the increasing adoption of cloud services necessitates a scalable and cost-efficient networking infrastructure. Space-division multiplexing (SDM) is considered as a promising solution to overcome the optical network capacity crunch and support cost-effective network capacity scaling. Multi-core fiber (MCF) is regarded as the most feasible and efficient way to realize SDM networks, and its deployment inside data centers seems very likely as the issue of inter-core crosstalk (XT) is not severe over short link spans (<1 km) compared to that in long-haul transmission. However, XT can still have a considerable effect in MCF over short distances,which can limit the transmission reach and in turn the data center's size. XT can be further reduced by bi-directional transmission of optical signals in adjacent MCF cores. This paper evaluates the benefits of MCF-based SDM solutions in terms of maximizing the capacity and spatial efficiency of data center networks. To this end, we present an analytical model for XT in bi-directional normal step-index and trench-assisted MCFs and propose corresponding XT-aware core prioritization schemes. We further develop XT-aware spectrum resource allocation strategies aimed at relieving the complexity of online XT computation. These strategies divide the available spectrum into disjoint bands and incrementally add them to the pool of accessible resources based on the network conditions. Several combinations of core mapping and spectrum resource allocation algorithms are investigated for eight types of homogeneous MCFs comprising 7-61 cores, three different multiplexing schemes, and three data center network topologies with two traffic scenarios. Extensive simulation results showthat combining bi-directional transmission in dense core fibers with tailored resource allocation schemes significantly increases the network capacity. Moreover, a multiplexing scheme that combines SDM and WDM can achieve up to 33 times higher link spatial efficiency and up to 300 times greater capacity compared to a WDM solution.

  • 333.
    Zhang, Lu
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab). Shanghai Jiao Tong Univ, State Key Lab Adv Opt Commun Syst & Networks, Shanghai 200240, Peoples R China..
    Chen, Jiajia
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Urban, Patryk J.
    Ericsson AB, Ericsson Res, S-16483 Stockholm, Sweden..
    Xiao, Shilin
    Shanghai Jiao Tong Univ, State Key Lab Adv Opt Commun Syst & Networks, Shanhai 200240, Peoples R China..
    Hu, Weisheng
    Shanghai Jiao Tong Univ, State Key Lab Adv Opt Commun Syst & Networks, Shanhai 200240, Peoples R China..
    Fixed and Mobile Convergence with Stacked Modulation2018In: 22ND INTERNATIONAL CONFERENCE ON OPTICAL NETWORK DESIGN AND MODELING (ONDM 2018) / [ed] Ruffini, M Tzanakaki, A Casellas, R Autenrieth, A MarquezBarja, JM, IEEE , 2018, p. 36-40Conference paper (Refereed)
    Abstract [en]

    We propose a stacked modulation mechanism to realize the transmission convergence of fixed broadband and wireless access networks. As an integrated solution, the direct current biased analog signal for wireless data is multiplied by the digital optical signal carrying fixed broadband service, where the low-speed analog signal becomes an envelope of the high-speed digital signal. At the receiver, the analog signal is firstly recovered with the image edge detection algorithm, after which the digital signal is recovered with the least-square algorithm. This scheme can realize fixed and mobile convergence with a single wavelength, which reduces the access network cost in terms of number of transceivers. Besides, the link capacity and spectrum efficiency are also improved. Moreover, this method is compatible with the existing access networks since the transceivers can be adopted to the scenario by turning off the unused modules. Simulation results show that in case of intensity modulation direct detection system sensitivity, penalty of only 1 similar to 2 dB can be obtained for the 10Gbps/lambda passive optical network when broadband access services are favored. Meanwhile, the wireless service needs more power than the broadband service to achieve the QoT requirements, and it has a higher penalty (similar to 5 dB) compared with broadband access services.

  • 334.
    Zhang, Lu
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab). State Key Laboratory of Advanced Optical Communication System and Networks, Shanghai Jiao Tong University, Shanghai, China.
    Pang, Xiaodan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab). Networking and Transmission Laboratory, RISE Acreo AB, Kista, Sweden.
    Ozolins, Oskars
    Udalcovs, Aleksejs
    Schatz, Richard
    KTH, School of Engineering Sciences (SCI).
    Westergren, Urban
    KTH, School of Engineering Sciences (SCI).
    Jacobsen, Gunnar
    Popov, Sergei
    KTH, School of Engineering Sciences (SCI).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Xiao, Shilin
    Hu, Weisheng
    Chen, Jiajia
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Digital mobile fronthaul employing differential pulse code modulation with suppressed quantization noise2017In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 25, no 25, p. 31921-31936Article in journal (Refereed)
    Abstract [en]

    A differential pulse code modulation (DPCM) based digital mobile fronthaul architecture is proposed and experimentally demonstrated. By using a linear predictor in the DPCM encoding process, the quantization noise can be effectively suppressed and a prediction gain of 7 similar to 8 dB can be obtained. Experimental validation is carried out with a 20 km 15-Gbaud/lambda 4-level pulse amplitude modulation (PAM4) intensity modulation and direct detection system. The results verify the feasibility of supporting 163, 122, 98, 81 20-MHz 4, 16, 64, 256 QAM based antenna-carrier (AxC) containers with only 3, 4, 5, 6 quantization bits at a sampling rate of 30.72MSa/s in LTE-A environment. Further increasing the number of quantization bits to 8 and 9, 1024 quadrature amplitude modulation (1024 QAM) and 4096 QAM transmission can be realized with error vector magnitude (EVM) lower than 1% and 0.5%, respectively. The supported number of AxCs in the proposed DPCM-based fronthaul is increased and the EVM is greatly reduced compared to the common public radio interface (CPRI) based fronthaul that uses pulse code modulation. Besides, the DPCM-based fronthaul is also experimentally demonstrated to support universal filtered multicarrier signal that is one candidate waveform for the 5th generation mobile systems.

  • 335. Zhou, L.
    et al.
    Held, M.
    Wosinska, Lena
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Analysis and optimization of connection availabilities in optical networks with different protection strategies2004In: Proc SPIE Int Soc Opt Eng, 2004, p. 157-167Conference paper (Refereed)
    Abstract [en]

    This work is motivated by interest in analyzing and optimizing availability of optical networks under different protection strategies. Methodology dealing with availability calculation, protection strategies, spare capacity, redundancy and sensitivity analysis is described. A case study calculates the availability of all connections within a long haul US-network using three protection strategies: path protection, span protection and protection-cycles. The distributions of connection down time of the three protection strategies are given. The availability optimization potential is estimated based on analysis of its sensitivity on reliability input data. Advantages and disadvantages of each strategy are compared from the availability and spare capacity requirement points of view.

  • 336.
    Zhu, Jing
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab). Univ Sci & Technol China, Sch Informat Sci & Technol, Hefei, Anhui, Peoples R China..
    Natalino, Carlos
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    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).
    Zhu, Zuqing
    Univ Sci & Technol China, Sch Informat Sci & Technol, Hefei, Anhui, Peoples R China..
    Control Plane Robustness in Software-Defined Optical Networks under Targeted Fiber Cuts2018In: 22ND INTERNATIONAL CONFERENCE ON OPTICAL NETWORK DESIGN AND MODELING (ONDM 2018) / [ed] Ruffini, M Tzanakaki, A Casellas, R Autenrieth, A MarquezBarja, JM, IEEE , 2018, p. 118-123Conference paper (Refereed)
    Abstract [en]

    The Software-Defined Optical Networking (SDON) paradigm enables programmable, adaptive and application-aware backbone networks. However, aside from the manifold advantages, the centralized Network Control and Management in SDONs also gives rise to a number of security concerns at different network layers. As communication between the control and the data plane devices in an SDON utilizes the common optical fiber infrastructure, it can be subject to various targeted attacks aimed at disabling the underlying optical network infrastructure and disrupting the services running in the network. In this work, we focus on the threats from targeted fiber cuts to the control plane (CP) robustness in an SDON under different link cut attack scenarios with diverse damaging potential, modeled through a newly defined link criticality measure based on the routing of control paths. To quantify the robustness of a particular CP realization, we propose a metric called Average Control Plane Connectivity (ACPC) and analyze the CP robustness for a varying number of controller instances in master/slave configuration. Simulation results indicate that CP enhancements in terms of controller addition do not necessarily yield linear improvements in CP robustness but require tailored CP design strategies.

  • 337. Öhlén, P.
    et al.
    Skubic, B.
    Rostami, A.
    Fiorani, Matteo
    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).
    Ghebretensaé, Z.
    Mårtensson, J.
    Wang, K.
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Data plane and control architectures for 5G transport networks2016In: Journal of Lightwave Technology, ISSN 0733-8724, E-ISSN 1558-2213, Vol. 34, no 6, p. 1501-1508, article id 7397818Article in journal (Refereed)
    Abstract [en]

    Next generation 5G mobile system will support the vision of connecting all devices that benefit from a connection, and support a wide range of services. Consequently, 5G transport networks need to provide the required capacity, latency, and flexibility in order to integrate the different technology domains of radio, transport, and cloud. This paper outlines the main challenges, which the 5G transport networks are facing and discusses in more detail data plane, control architectures, and the tradeoff between different network abstraction models.

4567 301 - 337 of 337
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