研究者詳細 - 山中　直明

論文 - 山中　直明

分割表示 279 件中 1 - 20 件目／全件表示 >>

Pod allocation algorithms to handle time-varying numbers of applications occurrence on the Access-Metro edge computing

Koki Muramatsu, Yoshihiko Uematsu, Satoru Okamoto, Naoaki Yamanaka

IEICE Communications Express 13 （ 2 ） 35 - 38 2024年02月

最終著者

AMec (Access-Metro edge computing) is a technology that can reduce the number of edge servers by utilizing in-network excess computing resources such as unallocated cores of control CPU of network devices as a node of the AMec cluster. The important issue is service interruption in that computing resources become unavailable due to executing their main job (e.g. device control and management jobs). In this paper, to avoid interruptions, two types of pod allocation algorithms (both static and dynamic thresholds) are evaluated. The dynamic threshold method is effective in keeping a high allocation success rate even for time-varying numbers of application occurrences.

Experimental Evaluation on Priority-aware Guaranteed Resource Allocation for Resource Pool Based Reconfigurable Hardware

Masaki Murakami, Takashi Kurimoto, Satoru Okamoto, Naoaki Yamanaka

IEEE/ACM Transactions on Networking (TNET) 2024年02月

最終著者

Networking Experiment of Domain-Specific Networking Platform Based on Optically Interconnected Reconfigurable Communication Processors

Murakami M., Kurimoto T., Okamoto S., Yamanaka N., Muranaka T.

IEICE Transactions on Communications （IEICE Transactions on Communications） E106–B （ 8 ） 660 - 668 2023年08月

ISSN 09168516

Access to Document (DOI)

Experimental Evaluation on Priority-Aware Guaranteed Resource Allocation for Resource Pool Based Reconfigurable Hardware

Murakami M., Kurimoto T., Okamoto S., Yamanaka N.

IEEE/ACM Transactions on Networking （IEEE/ACM Transactions on Networking） 32 （ 1 ） 298 - 307 2023年

共著, ISSN 10636692

This paper proposes a priority-aware guaranteed hardware resource allocation in virtual packet optical nodes (VPONs) and describes experimental evidence of service provisioning with the proposed method on testbed. A network based on the VPON brings solution of service diversification and traffic explosion because it provides multiple services by hardware level separated virtual networks such as IP/Ethernet/ Multi-Protocol Label Switching. The VPON has reconfigurable hardware which is dedicatedly allocated for each service and service-specific logical functions are implemented respectively. However, a previous hardware resource allocation method is not efficient. In previous work, the hardware resources once allocated to a service are not reallocated until the service terminated whenever the hardware is not optimally used. In recent years, hardware reconfiguration time has become shorter and it has enabled to apply for service demand change by releasing hardware from services with low demand and reallocating it to other services with high demand. Thus, this paper proposes preemptive dynamic hardware resource reallocation algorithm for VPON and a priority-aware guaranteed hardware resource reallocation method to realize efficient resource usage and high service capacity. Results of the computer simulation show improving service capability. Furthermore, to demonstrate the feasibility of service provisioning with the proposed method, emulators of the virtual packet optical node were constructed and performed resource reallocation. Results of the experiment show that the virtual packet optical node can configure function chains for providing services based on calculation results of the proposed resource reallocation method.

Access to Document (DOI)

Experiment of Nationwide Multi-Route Skew Cancelling for Dynamic Mapping of MAC Signals over SDM/WDM Network Testbed

Murakami M., Uematsu Y., Okamoto S., Yamanaka N., Soma D., Beppu S., Yoshikane N., Tsuritani T., Kodama T., Jinno M.

OECC/PSC 2022 - 27th OptoElectronics and Communications Conference/International Conference on Photonics in Switching and Computing 2022 （OECC/PSC 2022 - 27th OptoElectronics and Communications Conference/International Conference on Photonics in Switching and Computing 2022） 2022年

研究論文（国際会議プロシーディングス）, 共著

Access to Document (DOI)

Beyond 5G時代のネットワークビジョン -2030年に向けたアーキテクチャとブレークスルー技術の鳥瞰-

山中直明, 西村光弘, 石黒正揮, 岡崎義勝, 川西哲也, 釣谷剛宏, 中尾彰宏, 原井洋明, 廣岡俊彦, 古川英昭, 宮澤雅典, 山本直克, 吉野修一

電子情報通信学会和文論文誌B B, Vol. J104-B （ No. 3 ） 315 - 336 2021年03月

共著

Kalman filter-based heavy hadoop job detection method for energy efficient hybrid electro-optical intra-data center networks

Murakami M., Dubrana N., Uematsu Y., Okamoto S., Yamanaka N.

Optics InfoBase Conference Papers （Optics InfoBase Conference Papers） 2021年

共著

Deep programmable network architecture having URLLC-link for highly secure and manageable network

Naoaki Yamanaka, Satoru Okamoto, Takayuki Muranaka, Andrea Fumagalli

22nd Annual Conferece Net-Centric (Net-Centric 2020) Th2-1 2020年12月

研究論文（国際会議プロシーディングス）, 共著

Online parameter tuning of the flow classification method in the energy-efficient data center network HOLST

Murakami M., Kubokawa H., Sugiura K., Oki E., Okamoto S., Yamanaka N.

Journal of Optical Communications and Networking （Journal of Optical Communications and Networking） 12 （ 11 ） 344 - 354 2020年11月

共著, ISSN 19430620

An online parameter-tuning method for the energy-efficient data center network (DCN) named HOLST (high-speed optical layer 1 switch system for time-slot-switching-based optical data center networks) is proposed. HOLST comprises an optical circuit switching network, optical slot switching network, and electrical packet switching network for the spine layer. It requires flows to be assigned to optimal switches to achieve high power savings. In this study, first we experimentally confirm that the change in the DCN characteristics in the short term of actual data center traffic downgrades the accuracy of flow classification. Subsequently, we propose a procedure for reconfiguring a flow classification function and a method for online parameter tuning for this function. Finally, the accuracy of the flow classification method using the proposed tuning and estimated switching energy consumption in the spine layer are evaluated. The proposed online parameter-tuning function increases the accuracy of flow classification and reduces switching energy consumption relative to the conventional flow classification function.

Access to Document (DOI)

Cyber-physical system for autonomous driving vehicle considering with social welfare

Yamanaka N., Yamamoto G., Okamoto S., Fumagalli A.

International Conference on Transparent Optical Networks （International Conference on Transparent Optical Networks） 2020-July 2020年07月

研究論文（国際会議プロシーディングス）, 共著, ISSN 2161-2064

Autonomous driving vehicle control network by edge computer having very short response time has been constructed. Each vehicle has an agent program on the edge and communicated with adjacent vehicle agent in the cyber network. The advantage of connected vehicle control from stand-alone vehicle is sophisticated and total/ global optimizing control. The network edge computer calculated 'social welfare' which is the best benefit for all vehicle in the society. This paper describes control architecture and method at edge computer. In addition, some experimental results for controlling autonomous vehicle are also described.

Access to Document (DOI)

Experience with a Trans-Pacific Collaborative Mixed Reality Plant Walk

Vellingiri S., White-Swift J., Vania G., Dourty B., Okamoto S., Yamanaka N., Prabhakaran B.

Proceedings - 2020 IEEE Conference on Virtual Reality and 3D User Interfaces, VRW 2020 （Proceedings - 2020 IEEE Conference on Virtual Reality and 3D User Interfaces, VRW 2020） 238 - 245 2020年03月

研究論文（国際会議プロシーディングス）, 共著

In this paper, we share our experiences with a Trans-Pacific, collaborative mixed-reality (MR) based plant walk tour involving three geographical locations: (i) Dallas, Texas; (ii) Denver, Colorado; and (iii) Yokohama, Japan. The Wide Area Network (WAN) from Japan to Denver and from Denver to Dallas was through 100 Gbps optical links. These links were a mixture of leased and dedicated infrastructure. The average observed latency was around 131 ms and the maximum available bandwidth was 26.6 Gbps. The tour developed using a component-based framework, provided group travel with a leader-follower criterion involving a semi-active travel technique. By applying a 'modified Virtual Reality' (mVR) triangle paradigm, we examined the user experience of this collaborative tour. We considered Visualization, Synchronization, and Exploration design choices as the three key aspects of the mVR triangle. We assessed the user experience of the tour through a Gibbs triangle, with each of the composition of the Gibbs triangle being a key aspect of the mVR triangle. We obtained users' scores on the three aspects of the mVR using a seven-point, Likert scale questionnaire. We conducted 14 sessions of group travel. Overall, we found the user experience of the trans-pacific plant walk tour to be in the Balanced Experience Region (BER) region or the center part of the Gibbs triangle, which conveys that the majority of the participants experienced a balanced influence of mVR aspects throughout the tour.

Access to Document (DOI)

Autonomous driving vehicle controlling network using dynamic migrated edge computer function

Yamanaka N., Yamamoto G., Okamoto S., Muranaka T., Fumagalli A.

International Conference on Transparent Optical Networks （International Conference on Transparent Optical Networks） 2019-July 2019年07月

研究論文（国際会議プロシーディングス）

Autonomous driving vehicle control by edge computer network having very short response time has been proposed. Each vehicle has an agent program on the edge and automatically moved to adjacent edge computer following to the vehicle movement. On the edge computer, the agent program is processing with other vehicles' agents in a cyber network. We employ triple redundancy and majority rule to achieve high-reliability and less than 10 ms control latency try to be guaranteed. In addition, each vehicle has an IoT sensor including fine-GPS, so all precious position and speed of the vehicle can be monitored. We constructed the autonomous driving experimental course, the autonomous driving vehicle, and the edge computer system with the center cloud and tested in the campus test bed. According to the vehicle movement, network orchestrator setup a new optical path automatically and send the agent program to the adjacent target edge computer. This orchestration function is newly proposed application triggered dynamic optical network. In this presentation, I will show the detailed experimental results. This architecture and experimental results can be applied to the future smart and connected community.

Access to Document (DOI)

Experimental Evaluation of Application Triggered Flow Classification Using Operated Data Center Traffic Data

Murakami M., Matsuno M., Okamoto S., Yamanaka N.

OECC/PSC 2019 - 24th OptoElectronics and Communications Conference/International Conference Photonics in Switching and Computing 2019 （OECC/PSC 2019 - 24th OptoElectronics and Communications Conference/International Conference Photonics in Switching and Computing 2019） 2019年07月

研究論文（国際会議プロシーディングス）, 共著

Access to Document (DOI)

Experimental Deployment of Dynamic Resource Allocation Using Biological Attractor Selection in Virtual Packet Optical Node

Hara C., Murakami M., Okamoto S., Yamanaka N.

研究論文（国際会議プロシーディングス）, 共著

Access to Document (DOI)

Expected Capacity Guaranteed Routing based on Dynamic Link Failure Prediction

Sekigawa S., Okamoto S., Yamanaka N., Oki E.

2019 International Conference on Computing, Networking and Communications, ICNC 2019 （2019 International Conference on Computing, Networking and Communications, ICNC 2019） 170 - 174 2019年04月

研究論文（国際会議プロシーディングス）, 共著

In a high-speed backbone network, the failure of network links may cause large data losses, so it is necessary to reserve spare network resources for faster recovery. The conventional protection methods that reserve backup paths do not consider the failure probability of each network link and allocate same amount of network resources for the backup paths regardless of the failure rate of network links. This leads to the excessive or insufficient capacity allocation. This paper proposes the routing method that guarantees the expected value of the allocated capacity based on dynamically changed link failure rate. We formulate a Mixed Integer Liner Programming (MILP) model for the proposed method. We conduct simulations to investigate the effect of the expected capacity guaranteed routing over the conventional routing method in terms of bandwidth blocking probability, transmitted capacity achieved ratio, and the ratio of total transmitted capacity to total requested capacity. The results show that our proposed method marks higher transmitted capacity achieved ratio compared to conventional routing methods. We also find the transmitted capacity achieved ratio of the proposed method maintains 90% under high failure rate.

Access to Document (DOI)

A Span Power Management Scheme for Rapid Lightpath Provisioning and Releasing in Multi-Core Fiber Networks

Chatterjee B.C., He F., Oki E., Fumagalli A., Yamanaka N.

IEEE/ACM Transactions on Networking （IEEE/ACM Transactions on Networking） 27 （ 2 ） 734 - 747 2019年04月

共著, ISSN 10636692

The lightpath provisioning time or releasing time is adversely affected by the time that optical amplifiers require to adjust to a newly added or terminated signal power. This shortcoming is particularly true with multi-core erbium-doped amplifiers (EDFAs), as multi-core transient-suppressed EDFAs are unavailable at the current time. This paper proposes a fiber span power management scheme based on dummy wavelength signals that are used to shorten the lightpath provisioning and releasing times in multi-core fiber networks. With the shorter time of lightpath provisioning and releasing procedures, the total time that is required to reserve wavelengths in the system is decreased, which means that network resources are used more efficiently. As a result, the blocking performance and average waiting time in the system are improved. To evaluate the performance of the proposed scheme, this paper introduces both analytical model and simulation study. In the introduced model, the ratio of the number of activating and activated dummy wavelengths to the number of dummy wavelengths in each span is considered in the range between 0 and 1. The analysis reveals that the performance of the proposed scheme depends on \alpha , which is the ratio of the number of dummy wavelengths to the number of dummy and lightpath wavelengths in each span, and there exists a point of \alpha where the blocking probability becomes minimum. We further observe that the proposed scheme outperforms the conventional approaches in terms of blocking probability and average waiting time, as traffic loads increase. Finally, we provide the direction on how our introduced model can be considered for a network with multi-span routes.

Access to Document (DOI)

Designing a Hadoop system based on computational resources and network delay for wide area networks

Matsuno T., Chatterjee B., Kitsuwan N., Oki E., Veeraraghavan M., Okamoto S., Yamanaka N.

Telecommunication Systems （Telecommunication Systems） 70 （ 1 ） 13 - 25 2019年01月

共著, ISSN 10184864

This paper proposes a Hadoop system that considers both slave server’s processing capacity and network delay for wide area networks to reduce the job processing time. The task allocation scheme in the proposed Hadoop system divides each individual job into multiple tasks using suitable splitting ratios and then allocates the tasks to different slaves according to the computational capability of each server and the availability of network resources. We incorporate software-defined networking to the proposed Hadoop system to manage path computation elements and network resources. The performance of proposed Hadoop system is experimentally evaluated with fourteen machines located in the different parts of the globe using a scale-out approach. A scale-out experiment using the proposed and conventional Hadoop systems is conducted by executing both single job and multiple jobs. The practical testbed and simulation results indicate that the proposed Hadoop system is effective compared to the conventional Hadoop system in terms of processing time.

Access to Document (DOI)

Biological attractor selection and SDN control interworking in the virtual packet optical node network control

Hara C., Yarita K., Okamoto S., Yamanaka N.

Proceeding on 2019 Optical Fiber Communication, OFC2019, Session160 （Optics InfoBase Conference Papers） Part F160-OFC 2019 2019年

研究論文（国際会議プロシーディングス）, 共著

Modeling the effect of wavelength selective switch latency on optical flow switching performance

Shakeri A., Wang X., Razo M., Alabarce M., Oki E., Yamanaka N., Fumagalli A.

Journal of Optical Communications and Networking （Journal of Optical Communications and Networking） 10 （ 12 ） 924 - 935 2018年12月

共著, ISSN 19430620

Optical networks are well suited to enable massive data exchanges between datacenters. Elephant data flows can be routed over custom provisioned and dedicated lightpaths (optical flows) while other (mice) flows, which are routed by electronic switches, are unaffected. In some solutions, wavelength-selective switch (WSS) devices are employed in the optical nodes to physically and individually route each lightpath toward its destination. WSS devices take time to be switched and consequently delay the lightpath setup completion time. In this paper, the authors present three approximate Markov chain models to account for three different WSS service policies. These models estimate the expected lightpath setup and teardown time across an optical node that makes use of WSS devices. The first and more conventional policy (model) assumes that each setup and teardown request is handled individually, while the other two policies (models) assume that groups of setup and/or teardown requests are handled together by the WSS. The models' estimates are compared against the results obtained from a computer-based simulator, where both analytical models and simulator account for experimentally measured WSS response times. The simulator is also used to investigate the end-to-end lightpath setup time across an arbitrary mesh network. Results obtained from the models and simulator show that the group-based service policies outperform the conventional policy at high loads. The group-based policies are especially useful in the presence of lightpaths that are frequently set up and have relatively short holding time (i.e., short duration of elephant-optical flows).

Access to Document (DOI)

Experimental Demonstration of Disaggregated Emergency Optical System for Quick Disaster Recovery

Shiraiwa M., Yoshikane N., Xu S., Tsuritani T., Miyata N., Mori T., Miyabe M., Katagiri T., Yoshida S., Tanaka M., Hayashi T., Sugiyama H., Satou I., Mikuni M., Okamoto S., Yamanaka N., Jeong B., Awaji Y., Wada N.

Journal of Lightwave Technology （Journal of Lightwave Technology） 36 （ 15 ） 3083 - 3096 2018年08月

共著, ISSN 07338724

Disaggregation and white-box approaches are useful in expediting disaster recovery of optical transport networks. When an optical network system is damaged by a large disaster, the damaged devices can be replaced by the disaggregated functional devices, while disregarding vendor boundaries. In the light of the disaggregation and white-box approaches, we are developing a prototype of disaggregated portable emergency optical system (EOS) for early and low-cost postdisaster recovery. The EOS is customizable, and different functions can be selected to meet the different requirements in disaster recovery. In addition to replacing the damaged functions of the original optical system with an EOS, we introduce two new disaggregated functions into the EOS for postdisaster recovery. First, we introduce an optical supervisory channel handshake scheme to aid the interconnection of the surviving optical resources. Second, we introduce a scheme to achieve the quick recovery of the damaged control plane with the surviving or first restored wireless access capability. This is highly desired not only for emergency network control, but also for the quick collection of the network damage information. These two new functions have been implemented into the EOS prototype. We experimentally demonstrated the network recovery of the data-plane and the control-plane with the EOS.

Access to Document (DOI)

　前のページ - 次のページ　

山中 直明

論文 - 山中 直明

山中　直明

論文 - 山中　直明