The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform
Nageswara S. V. Rao - One of the best experts on this subject based on the ideXlab platform.
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BROADNETS - On transport methods for peak utilization of Dedicated Connections
Proceedings of the 6th International ICST Conference on Broadband Communications Networks and Systems, 2009Co-Authors: Nageswara S. V. RaoAbstract:Several research and production networks now provide multiple Gbps Dedicated Connections to meet the demands of large data transfers over wide-area networks. Application throughputs, however, were not able to match these rates because the traditional transport methods have not been optimized for such Connections. We propose a transport method based on stochastic approximation methods that: (a) stabilizes the source rate for peak utilization of Connection bandwidth, and (b) adapts the acknowledgment interval to maximize the goodput at the receiver. We show the asymptotic stability and convergence of this method in maximizing the throughput over Dedicated Connections under fairly general conditions. Extensive experimental results indicate the effectiveness of this transport method in achieving file transfer throughputs that closely match iperf bandwidth measurements on Dedicated Connections of several thousand miles over UltraScience Net and ESnet, and also illustrate its superior performance on a local Dedicated Connection in comparison with existing methods.
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QSHINE - Performance-Adaptive Prediction-Based Transport Control over Dedicated Links
Lecture Notes of the Institute for Computer Sciences Social Informatics and Telecommunications Engineering, 2009Co-Authors: Nageswara S. V. Rao, Zongmin WangAbstract:Several research and production networks now provide multiple Gbps Dedicated Connections to meet the demands of large data transfers over wide-area networks. End users, however, have not been able to see corresponding increase in application goodputs mainly because (i) such rates have pushed the bottleneck from the network to the end system, and (ii) the traditional transport methods are not optimized for handling host dynamics. Due to the sharing with unknown background workloads, the data receiver oftentimes lacks sufficient system resources to process packets arriving from high-speed Dedicated links, therefore leading to significant packet drops at the end system. We propose a rigorous design approach for a new class of transport protocols that explicitly account for the dynamics of the running environment to maximize application goodputs over Dedicated Connections. The control strategy of the proposed transport method combines two aspects: (i) the receiving bottleneck rate is predicted based on performance modeling, and (ii) the sending rate is stabilized at the estimated bottleneck rate based on stochastic approximation. We test the proposed method on a local Dedicated Connection and the experimental results illustrate its superior performance over existing methods.
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IPCCC - On Performance-Adaptive flow control for large data transfer in high speed networks
2009 IEEE 28th International Performance Computing and Communications Conference, 2009Co-Authors: Nageswara S. V. Rao, Zongmin WangAbstract:Several research and production high-performance networks now provision multi-Gbps Dedicated channels to meet the demands of large data transfers in network-intensive applications. However, end users have not seen corresponding increase in application throughput mainly because (i) the existence of high-bandwidth links has shifted the congestion from the network to end hosts, and (ii) such congestion is not well handled by TCP's Additive Increase and Multiplicative Decrease algorithm. Particularly, due to the sharing with unknown background workloads, the data receiver oftentimes lacks sufficient system resources to process the arriving packets, hence leading to significant packet drops at the end system. This paper proposes a UDP-based transport method that incorporates a performance-adaptive flow control mechanism to regulate the activities of both the sender and receiver in response to system dynamics to achieve high throughput. We construct a mathematical model for the socket receive buffer and data receiving process, and employ a profiling-based method to estimate the initial receiving bottleneck rate, which is dynamically adjusted and sent back to the sender for source rate control. The sending rate is stabilized at the estimated bottleneck rate based on a stochastic approximation algorithm. We test the proposed method on a local Dedicated Connection and the experimental results illustrate its superior performance over existing methods.
Motoyoshi Sekiya - One of the best experts on this subject based on the ideXlab platform.
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survivable impairment aware traffic grooming and regenerator placement with Dedicated Connection level protection
International Conference on Communications, 2011Co-Authors: Chengyi Gao, Hakki C Cankaya, Ankitkumar N Patel, Xi Wang, Qiong Zhang, Paparao Palacharla, Jason P Jue, Motoyoshi SekiyaAbstract:In this paper, we address the problem of survivable traffic grooming and regenerator placement in optical WDM networks with impairment constraints. The working Connections are protected end to end by provisioning bandwidth along a sequence of lightpaths through a Dedicated Connection-level protection scheme. An auxiliary-graph-based approach is proposed to address the placement of regenerators and grooming equipment for both working and Dedicated backup Connections in the network with the goal of minimizing the total equipment cost. Simulation results show that the proposed algorithm outperforms a lightpath-level protection algorithm, in which each lightpath is protected separately. We also show the effect of different cost models on equipment placement and evaluate the performance for networks with different line rates.
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ICC - Survivable Impairment-Aware Traffic Grooming and Regenerator Placement with Dedicated Connection Level Protection
2011 IEEE International Conference on Communications (ICC), 2011Co-Authors: Chengyi Gao, Hakki C Cankaya, Ankitkumar N Patel, Xi Wang, Qiong Zhang, Paparao Palacharla, Jason P Jue, Motoyoshi SekiyaAbstract:In this paper, we address the problem of survivable traffic grooming and regenerator placement in optical WDM networks with impairment constraints. The working Connections are protected end to end by provisioning bandwidth along a sequence of lightpaths through a Dedicated Connection-level protection scheme. An auxiliary-graph-based approach is proposed to address the placement of regenerators and grooming equipment for both working and Dedicated backup Connections in the network with the goal of minimizing the total equipment cost. Simulation results show that the proposed algorithm outperforms a lightpath-level protection algorithm, in which each lightpath is protected separately. We also show the effect of different cost models on equipment placement and evaluate the performance for networks with different line rates.
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Survivable impairment-aware traffic grooming and regenerator placement with shared Connection-level protection
2011 13th International Conference on Transparent Optical Networks, 2011Co-Authors: Chengyi Gao, Hakki C Cankaya, Ankitkumar N Patel, Xi Wang, Qiong Zhang, Paparao Palacharla, Jason P Jue, Motoyoshi SekiyaAbstract:In this paper, we address the problem of survivable traffic grooming and regenerator placement in optical WDM networks with impairment constraints. The working Connections are protected end to end by provisioning bandwidth along a sequence of lightpaths by using a shared Connection-level protection scheme. An auxiliary-graph-based approach is proposed to address the placement of regenerators and grooming equipment for both working and shared backup Connections in the network with the goal of minimizing the total equipment cost. Simulation results show that the proposed algorithm outperforms the Dedicated Connection-level protection algorithm as the load increases.
Gerhard Fettweis - One of the best experts on this subject based on the ideXlab platform.
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high performance dynamic resource allocation for guaranteed service in network on chips
IEEE Transactions on Emerging Topics in Computing, 2020Co-Authors: Yong Chen, Sadia Moriam, Emil Matus, Gerhard FettweisAbstract:This paper proposes a Dedicated Connection allocation unit—the NoCManager—implementing the Connection allocation functionality in circuit-switched network-on-chip (NoC) based on time-division-multiplexing (TDM). The NoCManager employs a novel trellis-search-algorithm (TESSA) that solves the allocation optimization problem by making use of dynamic programming approach. This enables to explore all possible paths between source-destination node pairs in order to determine the shortest available path. Three different trellis structures are proposed and analyzed for the purpose of different application scenarios. In contrast to previous TDM allocation approaches, the proposed method offers the following advantages: (1) hardware supported fast and high-throughput allocation mechanism; (2) improved success rate due to parallel multi-slot multi-path search mechanism; (3) selection of the contention-free shortest path with a guaranteed low latency; (4) general mathematical formulation allowing a variety of optimization ideas. The proposed method is compared to the state of the art centralized and distributed techniques under uniformly distributed random traffic as well as real-application traffic. The experimental results demonstrate two orders of magnitude improvement in allocation speed and tens of times higher success rate against the centralized software solutions, and 5 to 10 percent higher success rate against the centralized hardware solution. Moreover, it achieves up to 8x higher allocation speed and up to 29 percent higher success rate against recently proposed distributed solution.
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combined tdm and sdm circuit switching nocs with Dedicated Connection allocator
IEEE Computer Society Annual Symposium on VLSI, 2017Co-Authors: Yong Chen, Emil Matus, Gerhard FettweisAbstract:In general, circuit switching (CS) NoCs suffer from path diversity and resource utilization problem. Combining Time-Division Multiplexing (TDM) and Space-Division-Multiplexing (SDM) CS NoCs can reasonably mitigate this problem by increasing the path diversity and improving sharing of sub-channel among multiple Connections. In order to investigate and optimize TDM-SDM partitioning strategy, in this paper, we propose a Dedicated Connection allocator for combined TDM-SDM CS NoCs based on trellis-search algorithm, which can explore all possible paths between source-destination node pairs within a guaranteed latency. In contrast to the recently published approaches, we propose the novel bidirectional search that starts at source node and destination node simultaneously. Compared to previous unidirectional trellis search algorithms, our algorithm halves the search time while keeping the allocator area almost the same. In addition to this, we studied the influence of different TDM-SDM link partitioning strategies on success rate and path length that allowed us to find the optimal solution. The simulation results show our approach can improve the success rate by 25% to 42% compared to previous Connection allocation approaches.
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ISVLSI - Combined TDM and SDM Circuit Switching NoCs with Dedicated Connection Allocator
2017 IEEE Computer Society Annual Symposium on VLSI (ISVLSI), 2017Co-Authors: Yong Chen, Emil Matus, Gerhard FettweisAbstract:In general, circuit switching (CS) NoCs suffer from path diversity and resource utilization problem. Combining Time-Division Multiplexing (TDM) and Space-Division-Multiplexing (SDM) CS NoCs can reasonably mitigate this problem by increasing the path diversity and improving sharing of sub-channel among multiple Connections. In order to investigate and optimize TDM-SDM partitioning strategy, in this paper, we propose a Dedicated Connection allocator for combined TDM-SDM CS NoCs based on trellis-search algorithm, which can explore all possible paths between source-destination node pairs within a guaranteed latency. In contrast to the recently published approaches, we propose the novel bidirectional search that starts at source node and destination node simultaneously. Compared to previous unidirectional trellis search algorithms, our algorithm halves the search time while keeping the allocator area almost the same. In addition to this, we studied the influence of different TDM-SDM link partitioning strategies on success rate and path length that allowed us to find the optimal solution. The simulation results show our approach can improve the success rate by 25% to 42% compared to previous Connection allocation approaches.
Zongmin Wang - One of the best experts on this subject based on the ideXlab platform.
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QSHINE - Performance-Adaptive Prediction-Based Transport Control over Dedicated Links
Lecture Notes of the Institute for Computer Sciences Social Informatics and Telecommunications Engineering, 2009Co-Authors: Nageswara S. V. Rao, Zongmin WangAbstract:Several research and production networks now provide multiple Gbps Dedicated Connections to meet the demands of large data transfers over wide-area networks. End users, however, have not been able to see corresponding increase in application goodputs mainly because (i) such rates have pushed the bottleneck from the network to the end system, and (ii) the traditional transport methods are not optimized for handling host dynamics. Due to the sharing with unknown background workloads, the data receiver oftentimes lacks sufficient system resources to process packets arriving from high-speed Dedicated links, therefore leading to significant packet drops at the end system. We propose a rigorous design approach for a new class of transport protocols that explicitly account for the dynamics of the running environment to maximize application goodputs over Dedicated Connections. The control strategy of the proposed transport method combines two aspects: (i) the receiving bottleneck rate is predicted based on performance modeling, and (ii) the sending rate is stabilized at the estimated bottleneck rate based on stochastic approximation. We test the proposed method on a local Dedicated Connection and the experimental results illustrate its superior performance over existing methods.
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IPCCC - On Performance-Adaptive flow control for large data transfer in high speed networks
2009 IEEE 28th International Performance Computing and Communications Conference, 2009Co-Authors: Nageswara S. V. Rao, Zongmin WangAbstract:Several research and production high-performance networks now provision multi-Gbps Dedicated channels to meet the demands of large data transfers in network-intensive applications. However, end users have not seen corresponding increase in application throughput mainly because (i) the existence of high-bandwidth links has shifted the congestion from the network to end hosts, and (ii) such congestion is not well handled by TCP's Additive Increase and Multiplicative Decrease algorithm. Particularly, due to the sharing with unknown background workloads, the data receiver oftentimes lacks sufficient system resources to process the arriving packets, hence leading to significant packet drops at the end system. This paper proposes a UDP-based transport method that incorporates a performance-adaptive flow control mechanism to regulate the activities of both the sender and receiver in response to system dynamics to achieve high throughput. We construct a mathematical model for the socket receive buffer and data receiving process, and employ a profiling-based method to estimate the initial receiving bottleneck rate, which is dynamically adjusted and sent back to the sender for source rate control. The sending rate is stabilized at the estimated bottleneck rate based on a stochastic approximation algorithm. We test the proposed method on a local Dedicated Connection and the experimental results illustrate its superior performance over existing methods.
Chengyi Gao - One of the best experts on this subject based on the ideXlab platform.
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survivable impairment aware traffic grooming and regenerator placement with Dedicated Connection level protection
International Conference on Communications, 2011Co-Authors: Chengyi Gao, Hakki C Cankaya, Ankitkumar N Patel, Xi Wang, Qiong Zhang, Paparao Palacharla, Jason P Jue, Motoyoshi SekiyaAbstract:In this paper, we address the problem of survivable traffic grooming and regenerator placement in optical WDM networks with impairment constraints. The working Connections are protected end to end by provisioning bandwidth along a sequence of lightpaths through a Dedicated Connection-level protection scheme. An auxiliary-graph-based approach is proposed to address the placement of regenerators and grooming equipment for both working and Dedicated backup Connections in the network with the goal of minimizing the total equipment cost. Simulation results show that the proposed algorithm outperforms a lightpath-level protection algorithm, in which each lightpath is protected separately. We also show the effect of different cost models on equipment placement and evaluate the performance for networks with different line rates.
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ICC - Survivable Impairment-Aware Traffic Grooming and Regenerator Placement with Dedicated Connection Level Protection
2011 IEEE International Conference on Communications (ICC), 2011Co-Authors: Chengyi Gao, Hakki C Cankaya, Ankitkumar N Patel, Xi Wang, Qiong Zhang, Paparao Palacharla, Jason P Jue, Motoyoshi SekiyaAbstract:In this paper, we address the problem of survivable traffic grooming and regenerator placement in optical WDM networks with impairment constraints. The working Connections are protected end to end by provisioning bandwidth along a sequence of lightpaths through a Dedicated Connection-level protection scheme. An auxiliary-graph-based approach is proposed to address the placement of regenerators and grooming equipment for both working and Dedicated backup Connections in the network with the goal of minimizing the total equipment cost. Simulation results show that the proposed algorithm outperforms a lightpath-level protection algorithm, in which each lightpath is protected separately. We also show the effect of different cost models on equipment placement and evaluate the performance for networks with different line rates.
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Survivable impairment-aware traffic grooming and regenerator placement with shared Connection-level protection
2011 13th International Conference on Transparent Optical Networks, 2011Co-Authors: Chengyi Gao, Hakki C Cankaya, Ankitkumar N Patel, Xi Wang, Qiong Zhang, Paparao Palacharla, Jason P Jue, Motoyoshi SekiyaAbstract:In this paper, we address the problem of survivable traffic grooming and regenerator placement in optical WDM networks with impairment constraints. The working Connections are protected end to end by provisioning bandwidth along a sequence of lightpaths by using a shared Connection-level protection scheme. An auxiliary-graph-based approach is proposed to address the placement of regenerators and grooming equipment for both working and shared backup Connections in the network with the goal of minimizing the total equipment cost. Simulation results show that the proposed algorithm outperforms the Dedicated Connection-level protection algorithm as the load increases.
