Endre søk
Begrens søket
1 - 8 of 8
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Cheng, Yuxin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Passive Optical Top-of-Rack Interconnect for Data Center Networks2017Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Optical networks offering ultra-high capacity and low energy consumption per bit are considered as a good option to handle the rapidly growing traffic volume inside data center (DCs). However, most of the optical interconnect architectures proposed for DCs so far are mainly focused on the aggregation/core tiers of the data center networks (DCNs), while relying on the conventional top-of-rack (ToR) electronic packet switches (EPS) in the access tier. A large number of ToR switches in the current DCNs brings serious scalability limitations due to high cost and power consumption. Thus, it is important to investigate and evaluate new optical interconnects tailored for the access tier of the DCNs.

    We propose and evaluate a passive optical ToR interconnect (POTORI) architecture for the access tier. The data plane of the POTORI consists mainly of passive components to interconnect the servers within the rack as well as the interfaces toward the aggregation/core tiers. Using the passive components makes it possible to significantly reduce power consumption while achieving high reliability in a cost-efficient way.

    Meanwhile, our proposed POTORI’s control plane is based on a centralized rack controller, which is responsible for coordinating the communications among the servers in the rack. It can be reconfigured by software-defined networking (SDN) operation. A cycle-based medium access control (MAC) protocol and a dynamic bandwidth allocation (DBA) algorithm are designed for the POTORI to efficiently manage the exchange of control messages and the data transmission inside the rack.

    Simulation results show that under realistic DC traffic scenarios, the POTORI with the proposed DBA algorithm is able to achieve an average packet delay below 10 μs with the use of fast tunable optical transceivers. Moreover, we further quantify the impact of different network configuration parameters on the average packet delay. 

  • 2.
    Cheng, Yuxin
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Fiorani, Matteo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Lin, Rui
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    POTORI: A Passive Optical Top-of-Rack Interconnect Architecture for Data Centers2017Inngår i: Journal of Optical Communications and Networking, ISSN 1943-0620, E-ISSN 1943-0639, Vol. 9, nr 5, 401-411 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Several optical interconnect architectures inside data centers (DCs) have been proposed to efficiently handle the rapidly growing traffic demand. However, not many works have tackled the interconnects at top-of-rack (ToR), which have a large impact on the performance of the data center networks (DCNs) and can introduce serious scalability limitations due to their high cost and power consumption. In this paper, we propose a passive optical ToR interconnect architecture (POTORI) to replace the conventional electronic packet switch (EPS) in the access tier of DCNs. In the data plane, POTORI relies on a passive optical coupler to interconnect the servers within the rack and interfaces toward the aggregation/core tiers. The POTORI control plane is based on a centralized rack controller responsible for managing the communications among the servers in the rack. We propose a cycle-based medium access control (MAC) protocol to efficiently manage the exchange of control messages and the data transmission inside the rack. We also introduce and evaluate a dynamic bandwidth allocation algorithm for POTORI, namely largest first (LF). Extensive simulation results show that, with the use of fast tunable optical transceivers, POTORI and the proposed LF strategy are able to achieve an average packet delay below 10 μs under realistic DC traffic scenarios, outperforming conventional EPSs. On the other hand, with slower tunable optical transceivers, a careful configuration of the network parameters (e.g., maximum cycle time of the MAC protocol) is necessary to obtain a good network performance in terms of the average packet delay.

  • 3.
    Cheng, Yuxin
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Fiorani, Matteo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Centralized Control Plane for Passive Optical Top-of-Rack Interconnects in Data Centers2016Inngår i: 2016 IEEE Global Communications Conference, GLOBECOM 2016 - Proceedings, IEEE conference proceedings, 2016, 7841655Konferansepaper (Fagfellevurdert)
    Abstract [en]

    To efficiently handle the fast growing traffic inside data centers, several optical interconnect architectures have been recently proposed. However, most of them are targeting the aggregation and core tiers of the data center network, while relying on conventional electronic top-of-rack (ToR) switches to connect the servers inside the rack. The electronic ToR switches pose serious limitations on the data center network in terms of high cost and power consumption. To address this problem, we recently proposed a passive optical top-of-rack interconnect architecture, where we focused on the data plane design utilizing simple passive optical components to interconnect the servers within the rack. However, an appropriate control plane tailored for this architecture is needed to be able to analyze the network performance, e.g., packet delay, drop rate, etc., and also obtain a holistic network design for our passive optical top-of-rack interconnect, which we refer to as POTORI. To fill in this gap, this paper proposes the POTORI control plane design which relies on a centralized rack controller to manage the communications inside the rack. To achieve high network performance in POTORI, we also propose a centralized medium access control (MAC) protocol and two dynamic bandwidth allocation (DBA) algorithms, namely Largest First (LF) and Largest First with Void Filling (LFVF). Simulation results show that POTORI achieves packet delays in the order of microseconds and negligible packet loss probability under realistic data center traffic scenarios.

  • 4.
    Cheng, Yuxin
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Fiorani, Matteo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Reliability Analysis of Interconnects at Edge Tier in Datacenters2015Inngår i: 2015 17th International Conference on Transparent Optical Networks (ICTON), Institute of Electrical and Electronics Engineers (IEEE), 2015, UNSP We.C3.1Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The growing popularity of cloud based applications is drastically increasing the traffic volume that datacenters have to handle. This brings the need for scalable, reliable, and energy-efficient interconnection networks inside the datacenters. Optical communication has been considered as a promising technology for datacenter applications due to its high energy- and cost-efficiency at ultra-high capacity. A typical datacenter interconnection network includes several tiers. Figure 1 shows an example with three tiers: edge, aggregation and core. Due to the large number of active devices on top of the rack (ToR) energy consumption at the edge tier is dominating the overall power consumed by all the switches within the datacenter [1-2]. Several passive optical interconnect approaches [2-4] have been proposed showing that replacing active optical devices by passive ones is possible to significantly reduce both the hardware cost and energy consumption, achieve lower maintenance complexity and offer a sufficient level of scalability. [GRAPHICS] Furthermore, several topologies, e.g., fat-tree [5], Quartz [6], are investigated in order to improve the resiliency and scalability, particularly for large-scale datacenters. However, it should be noted that the redundancy for these proposed topologies is often added in the aggregation and core tiers rather than the edge tier, due to the cost issue. Although passive optical ToR solution by nature could provide better reliability performance than its active counterpart, the intra-rack communication may still need survivability strategies to meet very high connection availability requirement. For instance, the required availability of fault-tolerant datacenter infrastructure (including electrical power supply, storage and distribution facilities) should be higher than 99.995% [7]. Then the expected availability for any connection established within the datacenter needs to be even higher, since the communication system is only a part of the site infrastructure. In this regard, we analyse reliability performance of optical interconnects and identify the key part to be protected. Based on it, we propose some reliable passive optical interconnects for the edge tier of the datacenter interconnection networks. They can achieve ultra-high connection availability for intra-rack communications and adapt to any topology, e.g., fat-tree and Quartz, designed to increase scalability and reliability performance for the overall datacenter network.

  • 5.
    Cheng, Yuxin
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Fiorani, Matteo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Reliable and Cost Efficient Passive Optical Interconnects for Data Centers2015Inngår i: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 19, nr 11, 1913-1916 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To address the sustainability, scalability, and reliability problems that data centers are currently facing, we propose three passive optical interconnect (POI) architectures on top of the rack. The evaluation results show that all three architectures offer high reliability performance (connection availability for intra-rack interconnections higher than 99.999%) in a cost-efficient way.

  • 6.
    Lin, Rui
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Cheng, Yuxin
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Guan, Xun
    Tang, Ming
    Liu, Deming
    Chan, Chun-Kit
    Chen, Jiajia
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Optical Network Laboratory (ON Lab).
    Physical-layer network coding for passive optical interconnect in datacenter networks2017Inngår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 25, nr 15, 17788-17797 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We introduce physical-layer network coding (PLNC) technique in a passive optical interconnect (POI) architecture for datacenter networks. The implementation of the PLNC in the POI at 2.5 Gb/s and 10Gb/s have been experimentally validated while the gains in terms of network layer performances have been investigated by simulation. The results reveal that in order to realize negligible packet drop, the wavelengths usage can be reduced by half while a significant improvement in packet delay especially under high traffic load can be achieved by employing PLNC over POI.

  • 7. Pang, Z.
    et al.
    Cheng, Yuxin
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Johansson, M. E.
    Bag, G.
    Preliminary study on wireless home automation systems with both cloud-based mode and stand-alone mode2015Inngår i: Proceedings - 17th IEEE International Conference on Computational Science and Engineering, CSE 2014, Jointly with 13th IEEE International Conference on Ubiquitous Computing and Communications, IUCC 2014, 13th International Symposium on Pervasive Systems, Algorithms, and Networks, I-SPAN 2014 and 8th International Conference on Frontier of Computer Science and Technology, FCST 2014, 2015, 970-975 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    As the Smart Home segment is an intersection of numerous industries including consumer electronics, telecom, internet, and building automation, a Home Automation (HA) system requires flexible wireless communication architecture to not only take the advantages of wireless technologies such as reduced cost of installation and maintenance and improved user experiences but also fulfill the concerns of various industrial stakeholders. From this point-of-view, neither the pure Cloud-Based nor the Stand-Alone architecture is sufficient. In this paper, an IP-based hybrid architecture is presented which can support flexible combination of Could-Based Mode and Stand-Alone Mode. Preliminary prototyping based on the 6LoWPAN and experimental evaluation of performances have indicated the technical feasibility as well as future directions of improvement.

  • 8. Pang, Z.
    et al.
    Cheng, Yuxin
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Johansson, M. E.
    Bag, G.
    Work-in-progress: Industry-friendly and native-IP wireless communications for building automation2015Inngår i: Proceedings of the 2015 1st International Conference on Industrial Networks and Intelligent Systems, INISCom 2015, IEEE conference proceedings, 2015, 163-167 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Wireless communication technologies for building automation (BA) systems are evolving towards native IP connectivity. More Industry Friendly and Native-IP Wireless Building Automation (IF-NIP WiBA) is needed to address the concerns of the entire value chain of the BA industry including the security, reliability, latency, power consumption, engineering process, and independency. In this paper, a hybrid architecture which can seamless support both Cloud-Based Mode and Stand-Alone Mode is introduced based on the 6LoWPAN WSAN (wireless sensor and actuator networks) technology and verified by a prototyping minimal system. The preliminary experimental results suggest that, 1) both the WSAN and Cloud communications can meet the requirements of non-real-time application of BA systems, 2) the reliability and latency of the WSAN communications is not sufficient for soft real-time applications but it is not far away to meet such requirements by sufficient optimization in the near future, 3) the reliability of Cloud is pretty sufficient but the latency is quite far from the requirement of soft real-time applications. To optimize the latency and power consumption in WSAN, design industrial friendly engineering process, and investigate security mechanisms should be the main focus in the future.

1 - 8 of 8
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf