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Investigating an Adaptive network coding Control Protocol for Multihop-Multipath networks for network Reconfigurability

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Investigating an Adaptive Network Coding Control Protocol fo...

International Conference on Computers, Communications, and Systems (ICCCS)

作者： Zilole Simate Ryuji Kohno Physics Yokohama National University Yokohama Japan

ISBN: (纸本)9781538663516

One of the challenges in current designs of wireless networks is that of guaranteeing end to end delivery of high priority data or packets in multi-path multi-hop networks for medical use especially for nodes with mobility. There are various solutions based on traffic engineering which are applied in wired networks to guarantee end to end delivery of packets. With mobile wireless networks, the environment is highly dynamic, therefore with different scenarios having multiple paths or routes in the network, the node has to adapt to the network for dependable delivery of priority packets. In so doing, a level of Qos can at least be guaranteed. This paper reviews some of the techniques to achieve adaptive network coding, and the objective is to implement adaptive network coding in multi-hop, multipath network for high reliability and dependability. As a preliminary study we investigate an Adaptive network coding scheme in a Binary tree fashion with the root being the convolution coder for its feasibility. The objective is to design a control protocol to be used to adapt to the error changes that occur in the network thereby increasing performance.

关键词： network coding Adaptive systems Encoding Protocols Registers Quality of service Routing

Geo-network coding function virtualization for reliable communication over satellite

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arXiv 2018年

作者： Do-Duy, Tan Castro, M. Angeles Vazquez Dept. of Telecommunications and Systems Engineering Autonomous University of Barcelona Spain

In this paper, we propose a design solution for the implementation of Virtualized network coding Functionality (VNCF) over a service coverage area. network Function Virtualization (NFV) and network coding (NC) architectural designs are integrated as a toolbox of NC design domains so that NC can be implemented over different underlying physical networks including satellite or hybrid networks. The design includes identifying theoretical limits of NC over wireless networks in terms of achievable rate region and optimizing coding rates for nodes that implement VNCF. The overall design target is to achieve a given multicast transmission target reliability at receiver sides. In addition, the optimization problem uses databases with geo-tagged link statistics and geo-location information of network nodes in the deployment area for some computational complexity/energy constraints. Numerical results provide validation of our design solution on how network conditions and system constraints impact the design and implementation of NC and how VNCF allows reliable communication over wireless networks with reliability and connectivity up to theoretical limits. Copyright © 2018, The Authors. All rights reserved.

关键词： network coding

Energy Optimization for Cooperative Multipath Routing in MANETs using network coding

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Energy Optimization for Cooperative Multipath Routing in MAN...

International Conference on Advances in Computing, Communication Control and networking (ICACCCN)

作者： Saurabh Kumar Debasrit Mohanty Alisha Panda Lipsa Das Sandeep Nigam Soumyashree S. Panda Prakhar Golcha Srichandan Shobhanayak Department of Computer Science and Engineering IIIT Bhubaneswar India

ISBN: (纸本)9781538641200

In case of routing protocols in MANETs (Mobile Ad hoc networks), the most critical aspect is to take care of the energy consumption and efficiency during data transmission from source to destination[1]. During data transmission the relay nodes within the range of source node can access the data packets from the source node and transmit the packets to the destination node as per the destination address, then the original data is retrieved by the receiver(destination node) after decoding the received packet. But an optimal path that guarantees minimum consumption of energy during data transmission has maximum energy efficiency[2]. In this paper, we propose a method which ensures maximum energy efficiency. It is based on network-coding and Energy-Balancing for Cooperative-Multipath-Routing. In this paper, we have implemented the above technique by using NS2 and have evaluated energy efficiency and the consumption of energy when a packet of data is transmitted following a particular path through the relay nodes.

关键词： Ad hoc networks network coding Mobile computing Energy efficiency Routing Computer science Energy consumption

Performance analysis of network coding with IEEE 802.11 DCF in multi-hop wireless networks

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arXiv 2018年

作者： Kafaie, Somayeh Ahmed, Mohamed Hossam Chen, Yuanzhu Dobre, Octavia A. Department of Electrical and Computer Engineering Faculty of Engineering and Applied Science Memorial University St. John'sNLA1B 3X5 Canada Department of Computer Science Memorial University St. John'sNLA1B 3X5 Canada

network coding is an effective idea to boost the capacity of wireless networks, and a variety of studies have explored its advantages in different scenarios. However, there is not much analytical study on throughput and end-to-end delay of network coding in multi-hop wireless networks considering the specifications of IEEE 802.11 Distributed Coordination Function. In this paper, we utilize queuing theory to propose an analytical framework for bidirectional unicast flows in multi-hop wireless mesh networks. We study the throughput and end-to-end delay of inter-flow network coding under the IEEE 802.11 standard with CSMA/CA random access and exponential back-off time considering clock freezing and virtual carrier sensing, and formulate several parameters such as the probability of successful transmission in terms of bit error rate and collision probability, waiting time of packets at nodes, and retransmission mechanism. Our model uses a multi-class queuing network with stable queues, where coded packets have a non-preemptive higher priority over native packets, and forwarding of native packets is not delayed if no coding opportunities are available. Finally, we use computer simulations to verify the accuracy of our analytical model. Copyright © 2018, The Authors. All rights reserved.

关键词： network coding

Extending On-the-fly network coding by Interleaving for Avionic Satellite Links

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Extending On-the-fly Network Coding by Interleaving for Avio...

IEEE Conference on Vehicular Technology (VTC)

作者： Daniel Stolpmann Christoph Petersen Vanessa Eichhorn Andreas Timm-Giel Institute of Communication Networks (ComNets) Hamburg University of Technology Germany

ISBN: (纸本)9781538663592;9781538663585

Still today, aircraft disappear and crash without communicating their last position. Looking into details, satellite communications currently seems to be the only reliable way to connect and send data on long-distance flights. However, geostationary satellite systems suffer from high propagation delays making Forward Error Correction (FEC) schemes beneficial compared to error handling by retransmissions. In this paper, Random Linear network coding (RLNC) is proposed as a packet level FEC technique for high delay satellite communication. Using emulation, it is shown that correlated losses typical for a satellite channel result in a high variation in the number of redundant symbols required to decode a generation. This can be improved by using interleaving, which comes by the cost of an increased delay. A novel approach is introduced that combines On-the-fly coding and interleaving. This can significantly reduce the average delay introduced by interleaving and allows to efficiently overcome correlated losses in combination with network coding for time-critical applications.

关键词： Delays Encoding network coding Forward error correction Satellites Propagation delay Emulation

FlexONC: Joint cooperative forwarding and network coding with precise encoding conditions

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arXiv 2018年

作者： Kafaie, Somayeh Chen, Yuanzhu Ahmed, Mohamed Hossam Dobre, Octavia A. Faculty of Engineering and Applied Science Memorial University of Newfoundland St. John'sNLA1B 3X5 Canada Department of Computer Science Memorial University of Newfoundland St. John'sNLA1B 3X5 Canada

In recent years, network coding has emerged as an innovative method that helps a wireless network approach its maximum capacity, by combining multiple unicasts in one broadcast. However, the majority of research conducted in this area is yet to fully utilize the broadcasting nature of wireless networks, and still assumes fixed route between the source and destination that every packet should travel through. This assumption not only limits coding opportunities, but can also cause buffer overflow in some specific intermediate nodes. Although some studies considered scattering of the flows dynamically in the network, they still face some limitations. This paper explains pros and cons of some prominent research in network coding and proposes a Flexible and Opportunistic network coding scheme (FlexONC) as a solution to such issues. Furthermore, this research discovers that the conditions used in previous studies to combine packets of different flows are overly optimistic and would affect the network performance adversarially. Therefore, we provide a more accurate set of rules for packet encoding. The experimental results show that FlexONC outperforms previous methods especially in networks with high bit error rate, by better utilizing redundant packets spread in the network. Copyright © 2018, The Authors. All rights reserved.

关键词： network coding

SatNetCode: Functional Design and Experimental Validation of network coding over Satellite

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SatNetCode: Functional Design and Experimental Validation of...

International Symposium on networks, Computers and Communications (ISNCC)

作者： M. A. Vázquez-Castro P. Saxena T. Do-Duy TF. Vamstad H. Skinnemoen Department of Telecommunications and Systems Engineering Autonomous University of Barcelona Barcelona Spain AnsuR Technologies Oslo Norway

In this paper, we present the functional design and experimental validation of network coding technology over hybrid networks including satellite links. We first describe our design framework based on a holistic modelling of (overlay) heterogeneous networking satellite scenarios. We then define different types of logical nodes depending on their encoding, re-encoding and decoding functionalities and whether or not the satellite (overlay) application designer has control over them. Nodes are assumed strategically chosen to recode, which may result in a small number of re-encoding nodes that suffice to optimize selected performance metrics. Our main contribution is a system-oriented functional design of network coding that enables flexible instantiation of different types of network codes via configurable network coding (C-NC) functions. Random or structured NC coefficients can be remotely or locally generated and a packet scheduler can forward packets according to different policies. The choice of coefficients and overall NC scheme depend on the SATCOM-specific performance target, namely delay or bandwidth constraints. Here, we present a preliminary design and experimental testebed validation for the case of delay constrained transmission. Our results show the practical benefits of re-encoding and performance tradeoffs of different network coding schemes. In particular, our results show the good structural properties and delay-reliability tradeoffs of our novel proposal of structured network codes using Pascal matrices due to the regenerative properties of the coding coefficients.

关键词： network coding Encoding Satellites Delays Computer architecture Decoding

A network coding Approach to In-Band Control Traffic Sharing in Software Defined networks

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A Network Coding Approach to In-Band Control Traffic Sharing...

IEEE Conference on network Softwarization (NetSoft)

作者： Fayaz Akhtar Mubashir Husain Rehmani Alan Davy Telecommunications Software and Systems Group Waterford Institute of Technology Waterford Ireland

ISBN: (纸本)9781538646342

In-band southbound connectivity provides a cost-efficient way to share control traffic between the software-defined network controller and underlying forwarding devices; without having to worry about establishing and maintaining a separate transport network. However, the adoption of such a design also exposes the control plane traffic to non-negligible delay and losses; incurred from burdening a single transport network with an increased number of transmissions. These drawbacks can severely degrade network performance. For instance, when the requests in the form of control packets from switch-to-controller (or vice-versa) are dropped, the information may not get updated promptly and thus, the system would not behave as desired or in the worst case scenario can collapse altogether. To mitigate these constraints, in this paper, we propose the use of network coding which encourages information mixing as packets traverse the network. We show that network coding when applied to control plane traffic in an in-band design can help overcome losses due to congestion and link impairments. Evaluation results suggest that network coding aware in-band design can mitigate number of transmissions as well as total delay incurred by control packet losses.

关键词： Encoding Propagation losses network coding Delays Software Switches

Grassmannian codes with new distance measures for network coding

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arXiv 2018年

作者： Etzion, Tuvi Zhang, Hui Department of Computer Science Technion Haifa3200003 Israel Nanyang Technological University Singapore

Grassmannian codes are known to be useful in error-correction for random network coding. Recently, they were used to prove that vector network codes outperform scalar linear network codes, on multicast networks, with respect to the alphabet size. The multicast networks which were used for this purpose are generalized combination networks. In both the scalar and the vector network coding solutions, the subspace distance is used as the distance measure for the codes which solve the network coding problem in the generalized combination networks. In this work we show that the subspace distance can be replaced with two other possible distance measures which generalize the subspace distance. These two distance measures are shown to be equivalent under an orthogonal transformation. It is proved that the Grassmannian codes with the new distance measures generalize the Grassmannian codes with the subspace distance and the subspace designs with the strength of the design. Furthermore, optimal Grassmannian codes with the new distance measures have minimal requirements for network coding solutions of some generalized combination networks. The coding problems related to these two distance measures, especially with respect to network coding, are discussed. Finally, by using these new concepts it is proved that codes in the Hamming scheme form a subfamily of the Grassmannian codes. Copyright © 2018, The Authors. All rights reserved.

关键词： network coding