The Experts below are selected from a list of 117105 Experts worldwide ranked by ideXlab platform
Kun Liao - One of the best experts on this subject based on the ideXlab platform.
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an evolving scale free Network with large clustering coefficient
International Conference on Control Automation Robotics and Vision, 2006Co-Authors: Kun LiaoAbstract:Preferential attachment is generally regarded as the best mechanism to form scale-free Networks. However, the Simulated Network has a much smaller clustering coefficient, while many Networks in the real world, such as movie actors? collaboration and co-authorship Networks, have a high clustering coefficient. So we develop the Relatively Preferential Attachment (RPA) method which considers preferential attachment as well as the probability channel. RPA model can produce Networks which not only keep the scale free property but also have high clustering coefficient close to those of real Networks.
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ICARCV - An Evolving Scale-free Network with Large Clustering Coefficient
2006 9th International Conference on Control Automation Robotics and Vision, 2006Co-Authors: Kun LiaoAbstract:Preferential attachment is generally regarded as the best mechanism to form scale-free Networks. However, the Simulated Network has a much smaller clustering coefficient, while many Networks in the real world, such as movie actors? collaboration and co-authorship Networks, have a high clustering coefficient. So we develop the Relatively Preferential Attachment (RPA) method which considers preferential attachment as well as the probability channel. RPA model can produce Networks which not only keep the scale free property but also have high clustering coefficient close to those of real Networks.
Alexander Poylisher - One of the best experts on this subject based on the ideXlab platform.
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MILCOM - TimeSync: Virtual time for scalable, high-fidelity hybrid Network emulation
MILCOM 2012 - 2012 IEEE Military Communications Conference, 2012Co-Authors: Florin Sultan, Alexander Poylisher, Constantin Serban, Ritu Chadha John Lee, C. Jason ChiangAbstract:Hybrid Network emulation (HNE) comprises a discrete event Simulated Network and virtual machines that send and receive traffic through the Simulated Network. It allows testing Network applications rather than their models on Simulated target Networks, particularly mobile wireless Networks. Scalability of this test approach is hindered by the time divergence problem: for complex, large-scale simulations, discrete event simulation time advances slower than real time, distorting packet propagation characteristics. To address this problem, we developed TimeSync, a system that uses discrete event simulation time to control and synchronize time advance on virtual machines for large-scale hybrid Network emulation. In this paper, we describe how TimeSync controls and synchronizes time perception in hybrid Network emulation between simulator and virtual machines, and present experimental results.
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MSWiM - TimeSync: enabling scalable, high-fidelity hybrid Network emulation
Proceedings of the 15th ACM international conference on Modeling analysis and simulation of wireless and mobile systems - MSWiM '12, 2012Co-Authors: Florin Sultan, Alexander Poylisher, Constantin Serban, C. Jason Chiang, John Lee, Ritu Chadha, Keith Whittaker, Chris Scilla, Syeed AliAbstract:In this paper, we discuss a time synchronization approach to the time divergence problem in hybrid Network emulation. Such emulation comprises primarily a discrete-event Simulated Network and virtual machines that send and receive traffic through the Simulated Network. For slower than real-time Network simulations, the rate of time advance on virtual machines (real time) is faster than that of the discrete-event time. Consequently, packet transmission latency and other metrics in such hybrid Network emulations will be distorted. As a result, e.g., TCP sessions between virtual machines may unduly time out. To address this problem, we have developed TimeSync, which tracks discrete-event simulation time to control time advance on virtual machines for slower than real time simulations so that time perception in the hybrid Network emulation system is synchronized. We describe how TimeSync works and present our experimental evaluation and analysis.
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A virtual ad hoc Network testbed
2010Co-Authors: Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Robert Orlando, Cho-yu Jason Chiang, Kimberly JakubowskiAbstract:Testing of applications for ad hoc Networks poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate an ad hoc Network. This requires the development of technologies that enable multiple instances of unmodified application software on a set of hosts to communicate via a Simulated Network that behaves like a real ad hoc Network. In this paper, we describe the testbed developed under the virtual ad hoc Network (VAN) testbed project for testing applications over ad hoc Networks, with a special focus on Network management applications. The testbed employs Xen-based virtualisation to achieve resource scalability. The infrastructure for the testbed provides an integrated platform consisting of virtual nodes running the actual software under test, augmented with a Simulated Network environment. Our goal is to enable software testing over large-scale (500-1000 nodes) ad hoc Networks using the VAN testbed.
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virtual ad hoc Network testbeds for high fidelity testing of tactical Network applications
Military Communications Conference, 2009Co-Authors: Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Cho-yu J. Chiang, Kimberly Jakubowski, Robert OrlandoAbstract:Testing of applications for tactical MANETs poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate a tactical MANET to the highest feasible level of fidelity. For applications, this is achieved by executing unmodified software under real operating systems and realistic hardware resources. For the Network, it is achieved by using an emulated/Simulated Network that behaves like a real MANET in some/all layers of the protocol stack. In this paper, we describe the current state of Virtual Ad hoc Network (VAN) Testbed1 technologies for constructing testbeds that allow testing unmodified tactical applications over Simulated MANETs, including Network-aware applications. On the application side, we employ Xen-based virtualization to provide high fildelity of application execution environment, testbed resource scalability and manageability. On the Network side, we employ user-provided simulation models and enable seamless integration of the hosts that run the software under test with virtual nodes in a Simulated Network. Our goal is to enable running experiments over large-scale (500–1000 nodes) MANETs using VAN testbeds.
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TRIDENTCOM - An integrated testbed for Virtual Ad Hoc Networks
2009 5th International Conference on Testbeds and Research Infrastructures for the Development of Networks & Communities and Workshops, 2009Co-Authors: Pratik K. Biswas, Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Siun-chuon Mau, Cho-yu J. Chiang, Robert Orlando, Kimberly JakubowskiAbstract:Testing of applications for ad hoc Networks poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate an ad hoc Network. This requires the development of technologies that enable multiple instances of unmodified application software on a set of hosts to communicate via a Simulated Network that behaves like a real ad hoc Network. In this paper, we describe the testbed developed under the Virtual Ad hoc Network (VAN) project1 for testing applications over ad hoc Networks, with a special focus on Network management applications. The testbed employs Xen-based virtualization to achieve resource scalability. The infrastructure for the testbed provides an integrated platform consisting of virtual nodes running the actual software under test, augmented with a Simulated Network environment. Our goal is to enable software testing over large-scale (500–1000 nodes) ad hoc Networks using the VAN Testbed.
Kimberly Jakubowski - One of the best experts on this subject based on the ideXlab platform.
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A virtual ad hoc Network testbed
2010Co-Authors: Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Robert Orlando, Cho-yu Jason Chiang, Kimberly JakubowskiAbstract:Testing of applications for ad hoc Networks poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate an ad hoc Network. This requires the development of technologies that enable multiple instances of unmodified application software on a set of hosts to communicate via a Simulated Network that behaves like a real ad hoc Network. In this paper, we describe the testbed developed under the virtual ad hoc Network (VAN) testbed project for testing applications over ad hoc Networks, with a special focus on Network management applications. The testbed employs Xen-based virtualisation to achieve resource scalability. The infrastructure for the testbed provides an integrated platform consisting of virtual nodes running the actual software under test, augmented with a Simulated Network environment. Our goal is to enable software testing over large-scale (500-1000 nodes) ad hoc Networks using the VAN testbed.
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virtual ad hoc Network testbeds for high fidelity testing of tactical Network applications
Military Communications Conference, 2009Co-Authors: Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Cho-yu J. Chiang, Kimberly Jakubowski, Robert OrlandoAbstract:Testing of applications for tactical MANETs poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate a tactical MANET to the highest feasible level of fidelity. For applications, this is achieved by executing unmodified software under real operating systems and realistic hardware resources. For the Network, it is achieved by using an emulated/Simulated Network that behaves like a real MANET in some/all layers of the protocol stack. In this paper, we describe the current state of Virtual Ad hoc Network (VAN) Testbed1 technologies for constructing testbeds that allow testing unmodified tactical applications over Simulated MANETs, including Network-aware applications. On the application side, we employ Xen-based virtualization to provide high fildelity of application execution environment, testbed resource scalability and manageability. On the Network side, we employ user-provided simulation models and enable seamless integration of the hosts that run the software under test with virtual nodes in a Simulated Network. Our goal is to enable running experiments over large-scale (500–1000 nodes) MANETs using VAN testbeds.
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TRIDENTCOM - An integrated testbed for Virtual Ad Hoc Networks
2009 5th International Conference on Testbeds and Research Infrastructures for the Development of Networks & Communities and Workshops, 2009Co-Authors: Pratik K. Biswas, Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Siun-chuon Mau, Cho-yu J. Chiang, Robert Orlando, Kimberly JakubowskiAbstract:Testing of applications for ad hoc Networks poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate an ad hoc Network. This requires the development of technologies that enable multiple instances of unmodified application software on a set of hosts to communicate via a Simulated Network that behaves like a real ad hoc Network. In this paper, we describe the testbed developed under the Virtual Ad hoc Network (VAN) project1 for testing applications over ad hoc Networks, with a special focus on Network management applications. The testbed employs Xen-based virtualization to achieve resource scalability. The infrastructure for the testbed provides an integrated platform consisting of virtual nodes running the actual software under test, augmented with a Simulated Network environment. Our goal is to enable software testing over large-scale (500–1000 nodes) ad hoc Networks using the VAN Testbed.
Constantin Serban - One of the best experts on this subject based on the ideXlab platform.
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MILCOM - TimeSync: Virtual time for scalable, high-fidelity hybrid Network emulation
MILCOM 2012 - 2012 IEEE Military Communications Conference, 2012Co-Authors: Florin Sultan, Alexander Poylisher, Constantin Serban, Ritu Chadha John Lee, C. Jason ChiangAbstract:Hybrid Network emulation (HNE) comprises a discrete event Simulated Network and virtual machines that send and receive traffic through the Simulated Network. It allows testing Network applications rather than their models on Simulated target Networks, particularly mobile wireless Networks. Scalability of this test approach is hindered by the time divergence problem: for complex, large-scale simulations, discrete event simulation time advances slower than real time, distorting packet propagation characteristics. To address this problem, we developed TimeSync, a system that uses discrete event simulation time to control and synchronize time advance on virtual machines for large-scale hybrid Network emulation. In this paper, we describe how TimeSync controls and synchronizes time perception in hybrid Network emulation between simulator and virtual machines, and present experimental results.
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MSWiM - TimeSync: enabling scalable, high-fidelity hybrid Network emulation
Proceedings of the 15th ACM international conference on Modeling analysis and simulation of wireless and mobile systems - MSWiM '12, 2012Co-Authors: Florin Sultan, Alexander Poylisher, Constantin Serban, C. Jason Chiang, John Lee, Ritu Chadha, Keith Whittaker, Chris Scilla, Syeed AliAbstract:In this paper, we discuss a time synchronization approach to the time divergence problem in hybrid Network emulation. Such emulation comprises primarily a discrete-event Simulated Network and virtual machines that send and receive traffic through the Simulated Network. For slower than real-time Network simulations, the rate of time advance on virtual machines (real time) is faster than that of the discrete-event time. Consequently, packet transmission latency and other metrics in such hybrid Network emulations will be distorted. As a result, e.g., TCP sessions between virtual machines may unduly time out. To address this problem, we have developed TimeSync, which tracks discrete-event simulation time to control time advance on virtual machines for slower than real time simulations so that time perception in the hybrid Network emulation system is synchronized. We describe how TimeSync works and present our experimental evaluation and analysis.
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A virtual ad hoc Network testbed
2010Co-Authors: Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Robert Orlando, Cho-yu Jason Chiang, Kimberly JakubowskiAbstract:Testing of applications for ad hoc Networks poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate an ad hoc Network. This requires the development of technologies that enable multiple instances of unmodified application software on a set of hosts to communicate via a Simulated Network that behaves like a real ad hoc Network. In this paper, we describe the testbed developed under the virtual ad hoc Network (VAN) testbed project for testing applications over ad hoc Networks, with a special focus on Network management applications. The testbed employs Xen-based virtualisation to achieve resource scalability. The infrastructure for the testbed provides an integrated platform consisting of virtual nodes running the actual software under test, augmented with a Simulated Network environment. Our goal is to enable software testing over large-scale (500-1000 nodes) ad hoc Networks using the VAN testbed.
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virtual ad hoc Network testbeds for high fidelity testing of tactical Network applications
Military Communications Conference, 2009Co-Authors: Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Cho-yu J. Chiang, Kimberly Jakubowski, Robert OrlandoAbstract:Testing of applications for tactical MANETs poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate a tactical MANET to the highest feasible level of fidelity. For applications, this is achieved by executing unmodified software under real operating systems and realistic hardware resources. For the Network, it is achieved by using an emulated/Simulated Network that behaves like a real MANET in some/all layers of the protocol stack. In this paper, we describe the current state of Virtual Ad hoc Network (VAN) Testbed1 technologies for constructing testbeds that allow testing unmodified tactical applications over Simulated MANETs, including Network-aware applications. On the application side, we employ Xen-based virtualization to provide high fildelity of application execution environment, testbed resource scalability and manageability. On the Network side, we employ user-provided simulation models and enable seamless integration of the hosts that run the software under test with virtual nodes in a Simulated Network. Our goal is to enable running experiments over large-scale (500–1000 nodes) MANETs using VAN testbeds.
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TRIDENTCOM - An integrated testbed for Virtual Ad Hoc Networks
2009 5th International Conference on Testbeds and Research Infrastructures for the Development of Networks & Communities and Workshops, 2009Co-Authors: Pratik K. Biswas, Alexander Poylisher, Constantin Serban, John Lee, Ritu Chadha, Siun-chuon Mau, Cho-yu J. Chiang, Robert Orlando, Kimberly JakubowskiAbstract:Testing of applications for ad hoc Networks poses a special technical challenge due to the difficulty of conducting experiments in an ad hoc Network environment at a scale larger than a few nodes. One approach is to conduct experiments in a testbed that can imitate an ad hoc Network. This requires the development of technologies that enable multiple instances of unmodified application software on a set of hosts to communicate via a Simulated Network that behaves like a real ad hoc Network. In this paper, we describe the testbed developed under the Virtual Ad hoc Network (VAN) project1 for testing applications over ad hoc Networks, with a special focus on Network management applications. The testbed employs Xen-based virtualization to achieve resource scalability. The infrastructure for the testbed provides an integrated platform consisting of virtual nodes running the actual software under test, augmented with a Simulated Network environment. Our goal is to enable software testing over large-scale (500–1000 nodes) ad hoc Networks using the VAN Testbed.
Liam Kilmartin - One of the best experts on this subject based on the ideXlab platform.
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Hybrid testbed for simulating in-vehicle automotive Networks
Simulation Modelling Practice and Theory, 2016Co-Authors: Shane Tuohy, Martin Glavin, Edward Jones, Ciaran Hughes, Liam KilmartinAbstract:Abstract This paper presents a novel method of automotive Network simulation which is being used in an ongoing research effort to design cost effective, flexible in-vehicle Networks suitable for use in multi-camera, high bandwidth environments. The simulation platform uses a hybrid simulation approach, and allows the coexistence of real Network traffic streams and Simulated Network traffic. This approach provides a number of advantages, such as allowing for the injection and extraction of real Network streams from a Simulated Network topology. We present details of the testbed architecture and compare its performance to that of native systems. We also demonstrate that results obtained are in line with those in the literature. Finally, we describe novel experiments and applications made possible using the developed simulation platform and how it can be used in the evaluation and development of automotive video applications.
