研究発表

日本の通信トラヒックは, 年率約30%で増加を続けている. このため, 400 Gbps級のインタフェースを有する大容量L1/L2/L3ノードの導入が必要となる. また, 通信サービスの多様化も進展しており, 各サービスの多様なプロダクトライフサイクルに対応することが重要である. 上記課題への対応として, スマートフォトニックネットワーキング(SPN)が提案されている. 本稿では, SPN実現を目指して, リソースプール型の仮想通信処理プロセッサ(VRCP)を提案し, VRCPを用いたSPN向けプログラマブル光エッジ(PPE)構成を提案する.

2020年以降の実現を目指すスマートフォトニッククラウドが提案されている. スマートフォトニッククラウド実現のためには, スケールフリーフォトニクス, スマートフォトニックネットワーキング, シンセティックトランスポートプラットフォームの3S技術が必要である. 本稿では, スマートフォトニックネットワーキングにおける光L2網実現に向けて, シンセティックトランスポートプラットフォームの一部技術であるリソースプール型の仮想通信処理プロセッサを提案し, 仮想通信処理プロセッサを用いた光L2網のためのプログラマブル光エッジ構成を提案する.

Internet traffic volume continues to increase at a high rate every year. To handle unexpected traffic surges, link failures and growth in traffic volume, network link capacities are typically over-provisioned. To reduce the extent of over-provisioning, we proposed an application and network coordinated multi-layer architecture called ACTION. Application QoE (Quality of Experience) are translated into network QoS requirements, and the multi-layer architecture is leveraged to meet these QoS requirements. To determine the quality experienced by application flows, Hadoop logs are communicated to the network controller, and edge devices are programmed to detect elephant flows automatically. Virtual networks that offer applications flows their required QoS are realized by configuring physical network switches to achieve the required QoT (Quality of Transport). ACTION is a multi-QoE, application-centric, energy-efficient network architecture that leverages flexible elastic optical network technologies. This project is supported by both NSF, USA, and NICT, Japan, under the JUNO (Joint Japan-US Network Opportunity) program. This paper provides a brief overview of the project.

Geographically unconstrained remote control of an industrial robot for surface blending over multi-domain SDN-based optical transport networks is demonstrated, showing that cloud/edge computing technology improves controllability of the industrial robot.

In multi-carrier SDTN, Orchestrator-to-Orchestrator Interface is required since each carrier has its own orchestrator, whereas this interface is not defined. We propose a scheme to solve this issue and implement the proposed solution.

近年の通信トラヒック大容量化及び, 通信サービスの多様化に対応するため, フォトニックネットワーク及びノードの進展が求められており, 解決策としてスマートフォトニックネットワーキング(SPN)が提案されている. SPNでは, トランスポートに特化し, 広域, マルチドメインに対応した新たなレイヤ2(光L2)が求められている. 光L2においては, マルチドメインの一体運用, アドレス集約化によるルーティングの簡易化が求められており, 新たなアドレス体系の構築やブロードキャストを使用しないアドレス解決を行うことが求められる. 本稿では光L2網におけるマルチドメインに対応するためのアドレス割り当てについて検討した結果を報告する.

The first demonstration of the service restoration technique for metro-access networks successfully shows that ONU accommodated by the disaster-stricken central office is automatically re-connected within 10 sec to another office 20-km away with the same throughput as before disaster.

A Hadoop-based application triggered automatic flow switching method is proposed and examined in the hybrid electrical/optical data-center network environment. How to determine a shuffle-heavy job in the Hadoop cluster is investigated.

通信トラヒックの増大及び, 通信サービスの多様化に対応するためのフォトニックネットワーク及びノードの進展が求められており, 解決策としてスマートフォトニックネットワーキング(SPN) が提案されている. SPNでは, トランスポートに特化し, 広域・マルチドメンに対応した新たなレイヤ2 (光L2) が求められている. 本稿では, 光L2網における電気ラベル版フレーム構成を検討した結果を報告する.

近年のIoT(Internet of Things)の普及により, IoTデバイスの数が急激に増加している. その結果IoTサービスの処理負荷が増加している. 従来のIoTはシステムが垂直統合されており, 高い技術力とコストを必要としていた. また, 従来のIoTプラットフォームではデータセンタの処理負荷が膨大であり, リアルタイム性に欠けるという問題がある. そこで, 我々は新たに高いスケーラビリティと柔軟性を持つ水平統合型のIoTプラットフォームを提案する. 提案するIoTプラットフォーム上ではHGW(Home Gateway)がIoTサービスプログラムであるバンドルをライブマイグレーションし, 処理負荷分散を行う. ライブマイグレーションを行う際にIoTデバイスとバンドル間の遅延を小さくするために, ネットワーク距離が近いHGWを探索する手法が必要である.

In this paper, a data-center network (DCN) system that distinguishes Hadoop job types and allocates optical/electrical circuits to data flows depending on the types automatically is proposed. The proposed system calculates the predicted shuffle value (PSV) of the Hadoop job and determines which type of flow is allocated by comparing the PSV and the threshold value. The PSV can be calculated from a part of the input data based on the shuffle ratio, which is known to have a relationship to the heaviness of the shuffle phase of the Hadoop job. The threshold of PSV can be dynamically changed according to the network load condition to exploit the optical circuit efficiently. By orchestrating the DCN and the Hadoop system, the proposed system achieves the reduction of power consumption. In this study, the orchestration part of the proposed DCN system is implemented and the feasibility of switching data flows between optical and electrical circuits is verified.

This paper describes an experiment carried out to demonstrate robustness and trustworthiness of an orchestrated two-layer network test-bed (PROnet). A Robotic Operating System Industrial (ROS-I) distributed application makes use of end-to-end flow services offered by PROnet. The PROnet Orchestrator is used to provision reliable end-to-end Ethernet flows to support the ROS-I application required data exchange. For maximum reliability, the Orchestrator provisions network resource redundancy at both layers, i.e., Ethernet and optical. Experimental results show that the robotic application is not interrupted by a fiber outage.

In the smart grid, which is a new generation grid integrated with bidirectional communication and advanced information technology, it is supposed that the number of energy suppliers will increase because many renewable resources will be connected to the grid. The increase in the number of suppliers that use renewable energy resources introduces new challenges in scheduling and dispatching controllable resources to control the load of the power grid in the system. By using the pricing method that maximizes social welfare, consumers/suppliers can determine the optimal power consumption/generation that maximizes own welfare. However, when a forecast error of renewable energy output occurs, the gap between the total power consumption and generation causes unless consumers decrease power consumption from the optimal consumption. Decreasing consumers' power consumption might lower their utility.

In a high-speed backbone network, the failure of a network link may cause large data losses, so it is necessary to reserve spare network resources for faster recovery. The conventional protection methods to reserve backup routes do not consider the failure probability of each network link, so the same amount of network resources for the backup route are needed regardless of the failure probability of network links. This leads a decrease in the number of connections that can be accepted into the network. This paper proposes a routing and capacity allocation method that guarantees the expected value of allocated capacity. We formulate a mixed integer liner programming model for the proposed method. We conduct simulations to study the advantage of the expected capacity guaranteed routing over the conventional routing method in terms of bandwidth blocking probability. The results show that the proposed method reduces the bandwidth blocking probability to about 1/3 as compared to that of the conventional path protection method.

Recently, the energy consumption in data centers is increasing. Introducing optical circuit to the inter-rack communication is considered as an effective solution. The authors are working on the research and development of the High-speed Optical Layer 1 Switch system for Time slot switching based optical data center networks (HOLST). We focused on Plomb Lanthanum Zirconate Titanate (PLZT) optical switch that performs nano seconds switching time. In this paper, several ideas on how to connect PLZT optical switches and Micro Electro Mechanical Systems (MEMS) optical switches, the composing modules of the HOLST, are proposed to design network architecture and evaluated in order to compare and consider power saving effect. The result of the numerical simulation shows that the proposal architecture achieves 50% energy consumption reduction than the conventional architecture.