The Experts below are selected from a list of 17145 Experts worldwide ranked by ideXlab platform

Masahiko Jinno - One of the best experts on this subject based on the ideXlab platform.

  • Bandwidth Squeezed Restoration in Spectrum-Sliced Elastic Optical Path Networks (SLICE)
    Journal of Optical Communications and Networking, 2011
    Co-Authors: Yoshiaki Sone, Bartlomiej Kozicki, Atsushi Watanabe, Wataru Imajuku, Yukio Tsukishima, Hidehiko Takara, Masahiko Jinno
    Abstract:

    With the continuing growth in the amount of backbone traffic, improving the cost-effectiveness and ensuring survivability of the underlying Optical networks are very important problems facing network service providers today. In this paper, we propose a bandwidth squeezed restoration (BSR) scheme in our recently proposed spectrum-sliced elastic Optical path network (SLICE). The proposed BSR takes advantage of elastic bandwidth variation in the Optical Paths of SLICE. It enables spectrally efficient and highly survivable network recovery for best-effort traffic as well as bandwidth guaranteed traffic, while satisfying the service level specifications required from the client layer networks. We discuss the necessary interworking architectures between the Optical path layer and client layer in the BSR in SLICE. We also present a control framework that achieves flexible bandwidth assignment as well as BSR of Optical Paths in SLICE. Finally, we describe an implementation example of a control plane using generalized multi-protocol label switching (GMPLS).

  • experimental demonstration of spectrum sliced elastic Optical path network slice
    Optics Express, 2010
    Co-Authors: Bartlomiej Kozicki, Yukio Tsukishima, Hidehiko Takara, Toshihide Yoshimatsu, Kazushige Yonenaga, Masahiko Jinno
    Abstract:

    We describe experimental demonstration of spectrum-sliced elastic Optical path network (SLICE) architecture. We employ Optical orthogonal frequency-division multiplexing (OFDM) modulation format and bandwidth-variable Optical cross-connects (OXC) to generate, transmit and receive Optical Paths with bandwidths of up to 1 Tb/s. We experimentally demonstrate elastic Optical path setup and spectrally-efficient transmission of multiple channels with bit rates ranging from 40 to 140 Gb/s between six nodes of a mesh network. We show dynamic bandwidth scalability for Optical Paths with bit rates of 40 to 440 Gb/s. Moreover, we demonstrate multihop transmission of a 1 Tb/s Optical path over 400 km of standard single-mode fiber (SMF). Finally, we investigate the filtering properties and the required guard band width for spectrally-efficient allocation of Optical Paths in SLICE.

  • algorithms for maximizing spectrum efficiency in elastic Optical path networks that adopt distance adaptive modulation
    European Conference on Optical Communication, 2010
    Co-Authors: Tatsumi Takagi, Hiroshi Hasegawa, Ken-ichi Sato, Yoshiaki Sone, Bartlomiej Kozicki, Takafumi Tanaka, Masahiko Jinno
    Abstract:

    We propose Optical path routing and frequency slot assignment algorithms that suit elastic Optical Paths and the distance adaptive modulation scheme. The algorithms are proven to yield high spectrum efficiency for the distant-adaptive frequency allocation scheme.

  • gmpls based multiple failure recovery employing restoration scheme escalation in Optical path networks
    IEICE Transactions on Communications, 2009
    Co-Authors: Yoshiaki Sone, Naohide Nagatsu, Wataru Imajuku, Masahiko Jinno
    Abstract:

    Bolstering survivable backbone networks against multiple failures is becoming a common concern among telecom companies that need to continue services even when disasters occur. This paper presents a multiple-failure recovery scheme that considers the operation and management of Optical Paths. The presented scheme employs scheme escalation from pre-planned restoration to full rerouting. First, the survivability of this scheme against multiple failures is evaluated considering operational constraints such as route selection, resource allocation, and the recovery order of failed Paths. The evaluation results show that scheme escalation provides a high level of survivability even under operational constraints, and this paper quantitatively clarifies the impact of these various operational constraints. In addition, the fundamental functions of the scheme escalation are implemented in the Generalized Multi-Protocol Label Switching control plane and verified in an Optical-cross-connect-based network.

Ken-ichi Sato - One of the best experts on this subject based on the ideXlab platform.

  • architecture and design of quasi nyquist wdm networks with flexible grid granular switching
    2018 Photonics in Switching and Computing (PSC), 2018
    Co-Authors: Ryuta Shiraki, Hiroshi Hasegawa, Yojiro Mori, Ken-ichi Sato
    Abstract:

    Extremely high-density WDM networks that bundle and route Optical Paths are proposed; each path comprises a Nyquist-shaped signal. Bundled-based routing realizes finer-granularity frequency assignment than the ITU-T flexible grid and resolves spectrum narrowing at WSSs simultaneously. The number of fibers needed is reduced by 23% in a 16-node ring network.

  • spectral efficiency maximization of grouped routing Optical networks with shared protection
    IEEE\ OSA Journal of Optical Communications and Networking, 2017
    Co-Authors: Tomohiro Ishikawa, Hiroshi Hasegawa, Yojiro Mori, Ken-ichi Sato
    Abstract:

    Reliable coarse granular routing Optical network architectures that maximize fiber frequency utilization efficiency are presented. The architectures combine coarse granular routing and fine granular add/drop operations, where Optical Paths are carried by virtual Optical pipes. Higher efficiency than conventional fine granular routing networks is achieved by dense path packing in the frequency domain. We propose two architectures that apply shared protection with different levels of granularity and develop static network design algorithms for the two different shared protection schemes. The design algorithms neutralize the impairment caused by adjacent path dropping in the frequency domain. Numerical experiments verify that the necessary number of fibers in a network can be reduced by up to 20% due to the improved spectral utilization efficiency.

  • role of grouped routing in creating cost effective and bandwidth abundant networks
    International Conference on Transparent Optical Networks, 2017
    Co-Authors: Ken-ichi Sato
    Abstract:

    The continued increase in Internet traffic, particularly in metro networks, is spurring wide deployment of Optical networking technologies for wavelength routing. In metro networks, the number of nodes traversed can be very large and hence the Optical filtering penalty incurred in the ROADM/OXC nodes can be critical as it degrades fiber frequency utilization. This presentation elucidates how grouped routing, hierarchical Optical Paths, grouped routing entity pipes, and virtual direct routing, is effective.

  • architecture and design of Optical path networks utilizing waveband virtual links
    Proceedings of SPIE - The International Society for Optical Engineering, 2016
    Co-Authors: Yusaku Ito, Hiroshi Hasegawa, Yojiro Mori, Ken-ichi Sato
    Abstract:

    We propose a novel Optical network architecture that uses waveband virtual links, each of which can carry several Optical Paths, to directly bridge distant node pairs. Future photonic networks should not only transparently cover extended areas but also expand fiber capacity. However, the traversal of many ROADM nodes impairs the Optical signal due to spectrum narrowing. To suppress the degradation, the bandwidth of guard bands needs to be increased, which degrades fiber frequency utilization. Waveband granular switching allows us to apply broader pass-band filtering at ROADMs and to insert sufficient guard bands between wavebands with minimum frequency utilization offset. The scheme resolves the severe spectrum narrowing effect. Moreover, the guard band between Optical channels in a waveband can be minimized, which increases the number of Paths that can be accommodated per fiber. In the network, wavelength path granular routing is done without utilizing waveband virtual links, and it still suffers from spectrum narrowing. A novel network design algorithm that can bound the spectrum narrowing effect by limiting the number of hops (traversed nodes that need wavelength path level routing) is proposed in this paper. This algorithm dynamically changes the waveband virtual link configuration according to the traffic distribution variation, where Optical Paths that need many node hops are effectively carried by virtual links. Numerical experiments demonstrate that the number of necessary fibers is reduced by 23% compared with conventional Optical path networks.

  • algorithms for maximizing spectrum efficiency in elastic Optical path networks that adopt distance adaptive modulation
    European Conference on Optical Communication, 2010
    Co-Authors: Tatsumi Takagi, Hiroshi Hasegawa, Ken-ichi Sato, Yoshiaki Sone, Bartlomiej Kozicki, Takafumi Tanaka, Masahiko Jinno
    Abstract:

    We propose Optical path routing and frequency slot assignment algorithms that suit elastic Optical Paths and the distance adaptive modulation scheme. The algorithms are proven to yield high spectrum efficiency for the distant-adaptive frequency allocation scheme.

Bartlomiej Kozicki - One of the best experts on this subject based on the ideXlab platform.

  • Bandwidth Squeezed Restoration in Spectrum-Sliced Elastic Optical Path Networks (SLICE)
    Journal of Optical Communications and Networking, 2011
    Co-Authors: Yoshiaki Sone, Bartlomiej Kozicki, Atsushi Watanabe, Wataru Imajuku, Yukio Tsukishima, Hidehiko Takara, Masahiko Jinno
    Abstract:

    With the continuing growth in the amount of backbone traffic, improving the cost-effectiveness and ensuring survivability of the underlying Optical networks are very important problems facing network service providers today. In this paper, we propose a bandwidth squeezed restoration (BSR) scheme in our recently proposed spectrum-sliced elastic Optical path network (SLICE). The proposed BSR takes advantage of elastic bandwidth variation in the Optical Paths of SLICE. It enables spectrally efficient and highly survivable network recovery for best-effort traffic as well as bandwidth guaranteed traffic, while satisfying the service level specifications required from the client layer networks. We discuss the necessary interworking architectures between the Optical path layer and client layer in the BSR in SLICE. We also present a control framework that achieves flexible bandwidth assignment as well as BSR of Optical Paths in SLICE. Finally, we describe an implementation example of a control plane using generalized multi-protocol label switching (GMPLS).

  • experimental demonstration of spectrum sliced elastic Optical path network slice
    Optics Express, 2010
    Co-Authors: Bartlomiej Kozicki, Yukio Tsukishima, Hidehiko Takara, Toshihide Yoshimatsu, Kazushige Yonenaga, Masahiko Jinno
    Abstract:

    We describe experimental demonstration of spectrum-sliced elastic Optical path network (SLICE) architecture. We employ Optical orthogonal frequency-division multiplexing (OFDM) modulation format and bandwidth-variable Optical cross-connects (OXC) to generate, transmit and receive Optical Paths with bandwidths of up to 1 Tb/s. We experimentally demonstrate elastic Optical path setup and spectrally-efficient transmission of multiple channels with bit rates ranging from 40 to 140 Gb/s between six nodes of a mesh network. We show dynamic bandwidth scalability for Optical Paths with bit rates of 40 to 440 Gb/s. Moreover, we demonstrate multihop transmission of a 1 Tb/s Optical path over 400 km of standard single-mode fiber (SMF). Finally, we investigate the filtering properties and the required guard band width for spectrally-efficient allocation of Optical Paths in SLICE.

  • algorithms for maximizing spectrum efficiency in elastic Optical path networks that adopt distance adaptive modulation
    European Conference on Optical Communication, 2010
    Co-Authors: Tatsumi Takagi, Hiroshi Hasegawa, Ken-ichi Sato, Yoshiaki Sone, Bartlomiej Kozicki, Takafumi Tanaka, Masahiko Jinno
    Abstract:

    We propose Optical path routing and frequency slot assignment algorithms that suit elastic Optical Paths and the distance adaptive modulation scheme. The algorithms are proven to yield high spectrum efficiency for the distant-adaptive frequency allocation scheme.

  • distance adaptive spectrum allocation in elastic Optical path network slice with bit per symbol adjustment
    Optical Fiber Communication Conference, 2010
    Co-Authors: Bartlomiej Kozicki, Yoshiaki Sone, Atsushi Watanabe
    Abstract:

    We present a concept of spectrally-efficient Optical networking with distance-adaptive spectral allocation by adjusting the number of modulation levels. We demonstrate it by routing 40 Gb/s Optical Paths using short-reach, narrow-spectrum 16APSK and long-reach QPSK.

Yukio Tsukishima - One of the best experts on this subject based on the ideXlab platform.

  • Bandwidth Squeezed Restoration in Spectrum-Sliced Elastic Optical Path Networks (SLICE)
    Journal of Optical Communications and Networking, 2011
    Co-Authors: Yoshiaki Sone, Bartlomiej Kozicki, Atsushi Watanabe, Wataru Imajuku, Yukio Tsukishima, Hidehiko Takara, Masahiko Jinno
    Abstract:

    With the continuing growth in the amount of backbone traffic, improving the cost-effectiveness and ensuring survivability of the underlying Optical networks are very important problems facing network service providers today. In this paper, we propose a bandwidth squeezed restoration (BSR) scheme in our recently proposed spectrum-sliced elastic Optical path network (SLICE). The proposed BSR takes advantage of elastic bandwidth variation in the Optical Paths of SLICE. It enables spectrally efficient and highly survivable network recovery for best-effort traffic as well as bandwidth guaranteed traffic, while satisfying the service level specifications required from the client layer networks. We discuss the necessary interworking architectures between the Optical path layer and client layer in the BSR in SLICE. We also present a control framework that achieves flexible bandwidth assignment as well as BSR of Optical Paths in SLICE. Finally, we describe an implementation example of a control plane using generalized multi-protocol label switching (GMPLS).

  • experimental demonstration of spectrum sliced elastic Optical path network slice
    Optics Express, 2010
    Co-Authors: Bartlomiej Kozicki, Yukio Tsukishima, Hidehiko Takara, Toshihide Yoshimatsu, Kazushige Yonenaga, Masahiko Jinno
    Abstract:

    We describe experimental demonstration of spectrum-sliced elastic Optical path network (SLICE) architecture. We employ Optical orthogonal frequency-division multiplexing (OFDM) modulation format and bandwidth-variable Optical cross-connects (OXC) to generate, transmit and receive Optical Paths with bandwidths of up to 1 Tb/s. We experimentally demonstrate elastic Optical path setup and spectrally-efficient transmission of multiple channels with bit rates ranging from 40 to 140 Gb/s between six nodes of a mesh network. We show dynamic bandwidth scalability for Optical Paths with bit rates of 40 to 440 Gb/s. Moreover, we demonstrate multihop transmission of a 1 Tb/s Optical path over 400 km of standard single-mode fiber (SMF). Finally, we investigate the filtering properties and the required guard band width for spectrally-efficient allocation of Optical Paths in SLICE.

  • theoretical and experimental study of statistical decision method for link capacity adjustment
    Journal of Lightwave Technology, 2007
    Co-Authors: S Yamamoto, Ippei Shake, Tomohiko Kurahashi, Y Tarui, Wataru Imajuku, Yukio Tsukishima, Koji Sasayama, Osamu Moriwaki, Mitsunori Fukutoku
    Abstract:

    To utilize network resources effectively and guarantee the system reliability in Internet exchanges (IXs) in the future, the use of photonic IXs that employ Optical cross connects and generalized multiprotocol label switching is considered. This paper presents a theoretical and experimental study of link-capacity adjustment for a photonic IX employing a statistical-decision method for traffic monitoring. We present parameter estimation of the statistical-decision method in detail considering the traffic characteristics in IXs. Then, experiments on the link-capacity adjustment are presented. The first experiment shows the link-capacity adjustment of an Optical path to evaluate path addition from one path to two and path deletion from two Optical Paths to one. The second experiment shows the link-capacity adjustment using multiple Paths. We confirmed that there is no packet/frame loss in either experiment during the transmission of demo traffic, which simulates daily traffic changes.

Hidehiko Takara - One of the best experts on this subject based on the ideXlab platform.

  • Bandwidth Squeezed Restoration in Spectrum-Sliced Elastic Optical Path Networks (SLICE)
    Journal of Optical Communications and Networking, 2011
    Co-Authors: Yoshiaki Sone, Bartlomiej Kozicki, Atsushi Watanabe, Wataru Imajuku, Yukio Tsukishima, Hidehiko Takara, Masahiko Jinno
    Abstract:

    With the continuing growth in the amount of backbone traffic, improving the cost-effectiveness and ensuring survivability of the underlying Optical networks are very important problems facing network service providers today. In this paper, we propose a bandwidth squeezed restoration (BSR) scheme in our recently proposed spectrum-sliced elastic Optical path network (SLICE). The proposed BSR takes advantage of elastic bandwidth variation in the Optical Paths of SLICE. It enables spectrally efficient and highly survivable network recovery for best-effort traffic as well as bandwidth guaranteed traffic, while satisfying the service level specifications required from the client layer networks. We discuss the necessary interworking architectures between the Optical path layer and client layer in the BSR in SLICE. We also present a control framework that achieves flexible bandwidth assignment as well as BSR of Optical Paths in SLICE. Finally, we describe an implementation example of a control plane using generalized multi-protocol label switching (GMPLS).

  • experimental demonstration of spectrum sliced elastic Optical path network slice
    Optics Express, 2010
    Co-Authors: Bartlomiej Kozicki, Yukio Tsukishima, Hidehiko Takara, Toshihide Yoshimatsu, Kazushige Yonenaga, Masahiko Jinno
    Abstract:

    We describe experimental demonstration of spectrum-sliced elastic Optical path network (SLICE) architecture. We employ Optical orthogonal frequency-division multiplexing (OFDM) modulation format and bandwidth-variable Optical cross-connects (OXC) to generate, transmit and receive Optical Paths with bandwidths of up to 1 Tb/s. We experimentally demonstrate elastic Optical path setup and spectrally-efficient transmission of multiple channels with bit rates ranging from 40 to 140 Gb/s between six nodes of a mesh network. We show dynamic bandwidth scalability for Optical Paths with bit rates of 40 to 440 Gb/s. Moreover, we demonstrate multihop transmission of a 1 Tb/s Optical path over 400 km of standard single-mode fiber (SMF). Finally, we investigate the filtering properties and the required guard band width for spectrally-efficient allocation of Optical Paths in SLICE.