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arXiv 2018年

作者： Tashtarian, Farzad Erfanian, Alireza Varasteh, Amir Department of Computer Engineering Mashhad Branch Islamic Azad University Mashhad Iran Chair of Communication Networks Department of Electrical and Computer Engineering Technical University of Munich Germany

HTTP adaptive streaming (HAS) is quickly becoming the dominant video delivery technique for adaptive streaming over the Internet. Still considered as its primary challenges are determining the optimal rate adaptation and improving both the quality of experience (QoE) and QoE-fairness. Most of the proposed approaches have relied on local information to find a result. However, employing techniques that provide a comprehensive and central view of the network resources can lead to more gains in performance. By leveraging software defined networking (SDN), this paper proposes an SDN-based framework, named S 2V C, to maximize QoE metrics and QoE-fairness in SVC-based HTTP adaptive streaming. The proposed framework determines both the optimal adaptation and data paths for delivering the requested video files from HTTP-media servers to DASH clients. In fact, by utilizing an SDN controller and its complete view of the network, we introduce an SVC flow optimizer (SFO) application module to determine the optimal solution in a centralized and time slot fashion. In the current approach, we first formulate the problem as a mixed integer linear programming (MILP) optimization model. The MILP is designed in such a way that it applies defined policies, e.g. setting priorities for clients in obtaining video quality. Secondly, we show that this problem is NP-complete and propose an LP-relaxation model to enable S 2V C framework for performing rate adaptation on a large-scale network. Finally, we conduct experiments by emulating the proposed framework in Mininet, with the usage of Floodlight as the SDN controller. In terms of improving QoE-fairness and QoE metrics, the effectiveness of the proposed framework is validated by a comparison with different approaches. Copyright © 2018, The Authors. All rights reserved.

关键词： Quality of service

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The Control Algorithm and WSNB Operation of Log2(N,1,p) Switching Fabrics

The Control Algorithm and WSNB Operation of Log2(N,1,p) Swit...

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IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference

作者： Wojciech Kabacinski Marek Michalski Achille Pattavina Chair of Communication and Computer Networks Poznan University of Technology Poznan Poland Department of Electronics and Information Politecnico di Milano Italy

In this paper the new control algorithm for log 2 (N, 1, p) switching fabrics is proposed. This algorithm is the extension of the algorithm we propose for log 2 (N, 1, p) switching fabrics. The idea of the algorithm is to choose such a plane for the new connection in which this new connection will block the fewest number of possible future connections. Wide-sense nonblocking conditions are derived and proved when this algorithm is used for connection set up in such kind of switching fabrics with odd or even number of stages. The number of planes needed is the same as for the rearrangeable switching fabrics when the number of stages is even, and greater than for the rearrangeable switching fabric but lower than for the strict-sense nonblocking fabric, when the number of stages is odd.

关键词： Fabrics Switches Hardware Joining processes communication system control communication switching communications technology computer networks Books Routing

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A Roadmap to Future Space Connectivity 1

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丛书名： Signals and communication Technology

1000年

作者： Claudio Sacchi Fabrizio Granelli Riccardo Bassoli Frank H. P. Fitzek Marina Ruggieri

ISBN: (数字)9783031307621

ISBN: (纸本)9783031307614;9783031307645

This book provides an overview of the latest R&D advancements in the field of ICT technologies inherent to a New Space vision. The book presents a system-level and technology-level description of future space networking and communications. The authors also expand the vision to interplanetary networks. The book spans hardware and software technologies for future space communication networks, also considering very modern paradigms like quantum technologies and Softwarization. In the book, the word “space” is intended in a wider sense than the usual “satellite communications”, including new and partially unexplored fields like quantum space communications, interplanetary communications, and extra-terrestrial Radio Access networks (RANs). The book includes applications including Internet of Space Things, Tactile Internet/Digital twins for Space and discusses future challenges like those involved by the concept of “sustainable Space”.

关键词： communications Engineering, networks Microwaves, RF and Optical Engineering Aerospace Technology and Astronautics

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Experimental Study of Transport Layer Protocols for Wireless Networked Control Systems

Experimental Study of Transport Layer Protocols for Wireless...

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IEEE communications Society Conference on Sensor and Ad Hoc communications and networks (SECON)

作者： Polina Kutsevol Onur Ayan Nikolaos Pappas Wolfgang Kellerer Chair of Communication Networks Technical University of Munich Germany Department of Computer and Information Science Linköping University Linköping Sweden

In Wireless Networked Control Systems (WNCSs), the feedback control loops are closed over a wireless communication network. The proliferation of WNCSs requires efficient network resource management mechanisms since the control performance is significantly affected by the impairments caused by network limitations. In conventional communication networks, the amount of transmitted data is one of the key performance indicators. In contrast, in WNCSs, the efficiency of the network is measured by its ability to facilitate control applications, and the data transmission rate should be limited to avoid network congestion. In this work, we consider an experimental setup where multiple control loops share a wireless communication network. Our testbed comprises up to five control loops that include Zolertia Re-Mote devices implementing IEEE 802.15.4 standard. We propose a novel relevance- and network-aware transport layer (TL) scheme for WNCSs. The proposed scheme admits the most important measurements for the control process into the network while considering current network conditions. Moreover, we propose a mechanism for the scheme parameters adaptation in dynamic scenarios with unknown network statistics. Unlike the conventional TL mechanisms failing to provide adequate control performance due to either congestion in the network or inefficient utilization of available resources, our method prevents network congestion while keeping the control performance high. We argue that relevance- and network-awareness are critical components of network protocol design to avoid control performance degradation in practice.

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Dynamic Scheduling for Delay-Critical Packets in a Networked Control System Using WirelessHART

Dynamic Scheduling for Delay-Critical Packets in a Networked...

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IEEE International Conference on communications (ICC)

作者： Samuele Zoppi Jaya Prakash Champati James Gross Wolfgang Kellerer Chair of Communication Networks Technical University of Munich Germany School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Sweden

ISBN: (数字)9781728150895

ISBN: (纸本)9781728150901

In future industrial scenarios, Wireless Sensor networks (WSN) are envisioned to support the traffic of Networked Control Systems (NCS). WirelessHART is a prevalent WSN protocol that uses the Time Slotted Channel Hopping (TSCH) medium access to cope with the delay and reliability requirements of NCS in the harsh industrial environment. In TSCH, time slots and frequencies can be scheduled by a network coordinator to provide Quality of Service (QoS). In contrast to previous works that consider the end-to-end delay requirement of a flow of packets, we focus on a finite sequence of time-critical packets. These packets may belong to a time-critical message whose latency could significantly impact the NCS. Given an end-to-end delay deadline, our objective is to minimize the Delay Violation Probability (DVP) for a finite sequence of packets by dynamically scheduling the time slots in each frame. This is a challenging task as DVP depends on the instantaneous state of the network and requires its transient analysis. In this work, we model the wireless NCS as a two-queue lossy wireless network and propose the first transient analysis of DVP for a finite sequence of time-critical packets. Noting that DVP cannot be directly used for dynamic resource allocation, we propose a heuristic algorithm by relating DVP with the network's throughput. The proposed heuristic maximizes the expected throughput, is computed by solving a finite-horizon Markov Decision Process (MDP), and can be implemented at the network coordinator. Using simulation we demonstrate that the MDP-based heuristic achieves lower DVP compared to the classical MaxWeight and Weighted-Fair Queuing.

关键词： Delays Wireless sensor networks Reliability Dynamic scheduling Time factors Time division multiple access Quality of service

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Goal-Oriented Transport Layer Protocols for Wireless Control

Goal-Oriented Transport Layer Protocols for Wireless Control

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IEEE communications Society Conference on Sensor and Ad Hoc communications and networks (SECON)

Goal-oriented communication is a promising approach to tailor the network resource management algorithms to the needs of particular applications, thus enhancing the efficiency of resource utilization and boosting the application performance. In the context of distributed cyber-physical systems and networked control systems, the design of a control-aware transport layer (TL) represents a realistic approach for goaloriented communications since it can be integrated into generic control setups without making assumptions on particular hardware or network technologies and deliver enhanced end-to-end performance. This demo showcases the application performance of different TL schemes used for communication between the sensors and the controllers monitoring and actuating inverted pendulums, i.e., multi-dimensional plants. The nodes of the control loops are realized with Zolertia Re-Mote devices, and multiple control loops communicate over the shared wireless network using IEEE 802.15.4 standard. We use the demonstration testbed to compare the performance of conventional, state-of-the-art, and novel goal-oriented TL schemes by observing the emulated dynamics of inverted pendulums.

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Experimental Study of Transport Layer Protocols for Wireless Networked Control Systems

arXiv

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arXiv 2023年

作者： Kutsevol, Polina Ayan, Onur Pappas, Nikolaos Kellerer, Wolfgang Chair of Communication Networks Technical University of Munich Germany Department of Computer and Information Science Linköping University Linköping Sweden

In Wireless Networked Control Systems (WNCSs), the feedback control loops are closed over a wireless communication network. The proliferation of WNCSs requires efficient network resource management mechanisms since the control performance is significantly affected by the impairments caused by network limitations. In conventional communication networks, the amount of transmitted data is one of the key performance indicators. In contrast, in WNCSs, the efficiency of the network is measured by its ability to facilitate control applications, and the data transmission rate should be limited to avoid network congestion. In this work, we consider an experimental setup where multiple control loops share a wireless communication network. Our testbed comprises up to five control loops that include Zolertia Re-Mote devices implementing IEEE 802.15.4 standard. We propose a novel relevance- and network-aware transport layer (TL) scheme for WNCSs. The proposed scheme admits the most important measurements for the control process into the network while taking current network conditions into account. Moreover, we propose a mechanism for the scheme parameters adaptation in dynamic scenarios with unknown network statistics. Unlike the conventional TL mechanisms failing to provide adequate control performance due to either congestion in the network or inefficient utilization of available resources, our method prevents network congestion while keeping the control performance high. We argue that relevance- and network-awareness are critical components of network protocol design to avoid control performance degradation in practice. Copyright © 2023, The Authors. All rights reserved.

关键词： Closed loop control systems

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Boost Online Virtual Network Embedding: Using Neural networks for Admission Control 2016

Boost Online Virtual Network Embedding: Using Neural Network...

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Proceedings of the 12th Conference on International Conference on Network and Service Management

作者： Andreas Blenk Patrick Kalmbach Patrick van der Smagt Wolfgang Kellerer Chair of Communication Networks Department of Electrical and Computer Engineering Technical University of Munich Germany fortiss Associate Institute of Technical University of Munich Germany

ISBN: (纸本)9783901882852

The allocation of physical resources to virtual networks, i.e., the virtual network embedding (VNE), is still an on-going research field due to its problem complexity. While many solutions for the online VNE problem exist, only few have focused on methods that can be generally applied for optimization of online embeddings. In this paper, we propose an admission control based on a Recurrent Neural Network (RNN) to improve the overall system performance for the online VNE problem. Before running a VNE algorithm to embed a virtual network request, the RNN predicts whether the request will be accepted by the VNE algorithm based on the current state of the substrate and the virtual network request (VNR). The RNN prevents VNE algorithms from spending time on VNRs that are either infeasible or that cannot be embedded in acceptable time. In order to train and operate the RNN efficiently, we additionally propose new representations for substrate networks and virtual network requests. The representations are based on topological and network resource features to represent the substrate network and the VNRs with low computational complexity. Via simulations, we show that our admission control reduces the overall computational time for the online VNE problem by up to 91% while preserving VNE performance on average. Using our new substrate and request representations, the RNN achieves an accuracy ranging between 89% and 98% for different VNE algorithms, substrate sizes, and VNR arrival rates.

关键词： admission control mathematical optimization Virtual network embedding machine learning neural networks

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Passive YouTube QoE Monitoring for ISPs

Passive YouTube QoE Monitoring for ISPs

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International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing (IMIS)

作者： Raimund Schatz Tobias Hoßfeld Pedro Casas Telecommunications Research Center Vienna-FTW Vienna Austria Institute of Computer Science Chair of Communication Networks University of Würzburg Wurzburg Germany

Over the last decade, Quality of Experience (QoE) has become the guiding paradigm for enabling a more user-centric understanding of quality of communication networks and services. The intensifying competition among ISPs and the exponentially increasing traffic volumes caused by online video platforms like YouTube is forcing service providers to integrate QoE into their corporate DNA. This paper investigates the problem of YouTube QoE monitoring from an access provider's perspective. To this end, we present three novel methods for in-network measurement of the QoE impairment that dominates user perception in the context of HTTP video-streaming: stalling of playback. Our evaluation results show that it is possible to detect application-level stalling events at high accuracy by using network-level passive probing only. However, only the most complex and most accurate approach can be used for QoE prediction due to the non-linear ties inherent in human quality perception.

关键词： Streaming media YouTube Monitoring Quality of service Approximation methods Data mining Accuracy

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Machine Learning Based Study of QoE Metrics in *** Live Streaming

Machine Learning Based Study of QoE Metrics in *** Live Stre...

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IEEE Symposium on Network Operations and Management

作者： Frank Loh Kathrin Hildebrand Florian Wamser Stefan Geißler Tobias Hoßfeld Chair of Communication Networks University of Würzburg Germany School of Computer Science and Information Technology Lucerne University of Applied Sciences and Arts Switzerland

Video streaming generates most network traffic in today’s Internet. For that reason, video on demand streaming is researched heavily in recent years, and many traffic monitoring mechanisms, flow and stream models, and models to predict the user perceived quality are well established. However, the quickly growing live streaming sector is not considered in these Quality of Experience models and not even the relation between network traffic and playback quality has been studied so far, forming a gap in literature. For that reason, we investigate *** streaming as one of the largest live streaming platforms based on a large dataset and investigate the possibility to predict live streaming quality based on uplink request information. We apply approaches that are well studied for on demand streaming to predict quality changes, playback quality, and video interruption events as the most important metrics impairing user perceived quality. In this context, we answer whether these models are suitable for live streaming, if small changes are sufficient for satisfactory prediction results, or if fundamental changes and new models are required.

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