With the consolidation of Industry 4.0, IIoT (Industrial IoT) environments are becoming more common. Communications in these scenarios are mostly wireless, and due to the lossy nature of wireless links, loss of inform...
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ISBN:
(纸本)9781450372077
With the consolidation of Industry 4.0, IIoT (Industrial IoT) environments are becoming more common. Communications in these scenarios are mostly wireless, and due to the lossy nature of wireless links, loss of information becomes an intrinsic problem. Conventional recovery schemes come at cost, since they increase the delay. On the other hand, both reliability (robustness) and low delay are crucial requirements for IIoT. An interesting strategy to improve both of them is the use of network coding techniques, which have shown promising results, in terms of increased reliability and performance. Besides improving communication performance, network coding techniques enable a more efficient multi-cloud storage, which is often used in IIoT. This thesis aims at finding a network coding based solution that would efficiently respond to IIoT needs.
The concept of network coding has greatly evolved since its inception. Theoretical and achievable performance have been obtained for a wide variety of networking assumptions and performance objectives. Even if powerfu...
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ISBN:
(纸本)9783319254791;9783319254784
The concept of network coding has greatly evolved since its inception. Theoretical and achievable performance have been obtained for a wide variety of networking assumptions and performance objectives. Even if powerful, such a broad applicability poses a challenge to a unified design approach over different communication networks and systems. In this work, we propose a (non-reductionist) unified network coding design architectural framework where an ontology of abstraction domains is introduced rather than layer/system/network-specific assumptions and designs. The framework brings together network and system design and seems compatible with upcoming (more general) design frameworks such as software-defined networking, cognitive networking or network virtualization. We illustrate its applicability showing the case of network coding design over DVB-S2X/RCS.
network coding-based overhearing management policies can greatly improve coding ratio and system throughput of coding nodes. The existing strategies, such as FIFO, best effort service, and historical information-based...
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ISBN:
(纸本)9781479964475
network coding-based overhearing management policies can greatly improve coding ratio and system throughput of coding nodes. The existing strategies, such as FIFO, best effort service, and historical information-based etc, are all based on isolation mechanism of the node information, they do not fully consider the relation among the cached information of nodes, as a result, the node cache information is frequently replaced or deleted by mistake, affecting the coding ratio of coding nodes and the decoding ratio of destination nodes. Therefore, there is a lot of space for improvement. In "X" pattern network topology, network coding overhearing policy based on data packet switching and sorting algorithm is proposed in this article. First, when overhearing buffer is full, meanwhile, the sink codes have listened new packets, codes will drop the new packets but record the IDs of the dropped packets;Second, intermediate codes get the packets information of overhearing buffer by the means of improved Epidemic Algorithm, then sort the packets of coding queue according to the packets information of overhearing cache. Finally, sink nodes delete the packets which have been used for decoding, and add the newly-coming packets in the cache. Theoretical analysis and simulation demonstrate that the improved algorithm gets better coding ratio, higher system throughput and lower delay than the traditional overhearing policies.
We propose a new scheme for creating replica based on network coding in grid environments. For creating replica with network coding, there are two models: encoding between blocks of a replica and encoding between bloc...
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ISBN:
(纸本)9783642118418
We propose a new scheme for creating replica based on network coding in grid environments. For creating replica with network coding, there are two models: encoding between blocks of a replica and encoding between blocks of different replicas. The former is based on a butterfly-shaped topology, and the latter, in theory, based on any topology with a node more than one degree. Based on the latter model, furthermore, in practice, we propose a double-funnel-shaped topology. To evaluate our models, we extend NS2 by improving functions, modifying and adding classes. Compare to traditional strategies of creating replica, our experiment showed the strategy with network coding can improve data access time and I/O bottlenecks, low bandwidth consumption, or improve load balancing, increase robustness for being in support of departure of nodes.
network coding (NC) is known as a promising approach to improve the cooperative communication network throughput. However, in certain situations, it can introduce additional noise terms which is recently referred to a...
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ISBN:
(纸本)9781457713484
network coding (NC) is known as a promising approach to improve the cooperative communication network throughput. However, in certain situations, it can introduce additional noise terms which is recently referred to as NC noise. We consider such a problem in a two-unicast wireless system and seek to answer the following question: "Can we reduce or remove network coding noise by proper power allocation at the relay?" To this end, we provide a mathematical framework for the output signal-to-noise (SNR) ratio and instantaneous sum-rate of the network-coded cooperative communication (NC-CC) system with the notion of power assignment at the relay. Based on this framework, we provide two novel closed-form power allocation techniques that are suitable for slow and fast fading conditions. Numerical analysis is used to confirm the accuracy of the derived theory and to show the effectiveness of proposed solutions in terms of average sum-rate and outage probability. It is shown that such techniques offer a significant advantage in overcoming the adverse effects of NC noise, especially in slow fading, without introducing significant extra costs or system complexity.
network virtualization is believed to be a promising way for the next generation Internet to overcome network ossification. It allows multiple heterogeneous virtual networks (VNs) to be embedded onto the shared substr...
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network virtualization is believed to be a promising way for the next generation Internet to overcome network ossification. It allows multiple heterogeneous virtual networks (VNs) to be embedded onto the shared substrate network (SN) to offer more flexibility and better manageability. With the increasing deployments of VNs in a variety of networks, how to protect the VNs against the single substrate link failure has become a key challenge. In this paper, we propose a survivable VN link protection method based on network coding and protection circuit. First, we provide an integer linear programming formulation for the survivable VN link protection to maximize the long-term average revenue to cost ratio. Second, a novel protection circuit technology is introduced to augment the VN at the VN level to reduce the backup resource consumption and provide more flexible VN management. Then, an efficient heuristic virtual network embedding algorithm is developed, which makes full use of the limited resources and transforms the single substrate link protection into the single virtual link protection in multiple protection circuits. Finally, the data units from different links are encoded using network coding, which not only provides 1 + N protection to virtual links but also reduces the recovery delay. The evaluation results show that our method not only has the best acceptance ratio and long-term average revenue to cost ratio, but it also greatly enhances the achievable backup sharing and shortens the average network recovery delay.
Robust video multicast in erasure networks using network coding (NC) to reduce the impact of packet loss is studied in this paper. In our proposed solution, random linear network coding (RLNC) is adopted at intermedia...
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Robust video multicast in erasure networks using network coding (NC) to reduce the impact of packet loss is studied in this paper. In our proposed solution, random linear network coding (RLNC) is adopted at intermediate nodes of the network. RLNC linearly combines a group of packets by randomly selecting weighting coefficients on a finite field, and the loss of an RLNC-coded packet is equivalent to the loss of one constraint in a linear system of equations required for RLNC decoding. Unless the global coding coefficient matrix, or simply called the global coding matrix (GCM), is of full rank, a receive node cannot reconstruct all source packets. To address this rank deficiency problem, we propose to construct a special-structured GCM, called the ladder-shaped GCM (LGCM), for layered H.264/SVC (scalable video coding) video multicast. The ladder shape of the sparse coding matrix is maintained throughout the RLNC process to achieve two objectives: (1) to enable partial decoding of a block;and (2) to provide unequal erasure protection for H.264/SVC priority layers. Furthermore, quality degradation is minimized by optimizing the amount of redundancy assigned to each layer, and graceful quality degradation is achieved by error concealment (EC). Simulation results are given to demonstrate the superior performance of the proposed RLNC-LGCM scheme over the traditional RLNC with a general GCM. (C) 2010 Elsevier Inc. All rights reserved.
network coding opportunistic routing (NCOR) offers a promising solution for efficient data transmission in delay tolerant networks. Due to the multi-copy strategy and network coding nature, NCOR inevitably brings abou...
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network coding opportunistic routing (NCOR) offers a promising solution for efficient data transmission in delay tolerant networks. Due to the multi-copy strategy and network coding nature, NCOR inevitably brings about a large number of heterogeneous copies, leading to over-consumption of limited network resources. To alleviate this situation, it is imperative to study how to reduce redundant copies in the network. In this paper, we propose a pre-decoding recovery mechanism (PDRM) that removes residual copies after the destination node obtains the original packet information. The PDRM consists of three operations: generating pre-decoding elements, maintaining immune-lists, and deleting redundant copies. In particular, the destination node generates a pre-decoding element, and then, sends it to other nodes in the network via an immune-list to help remove the residual copies. Here, the pre-decoding element is an acknowledgement indicating that the destination node has the necessary information to decode the corresponding original packet. As the core of the PDRM, the first operation enables the destination node to generate a pre-decoding element for each innovative packet without waiting for decoding the generation. Simulation results demonstrate that the PDRM achieves excellent results in improving network performance, and outperforms the existing recovery mechanism.
A pair of terminals exchanging information via a layer of parallel relay nodes under slow fading is considered. Two protocols are proposed based on the combination of opportunistic relaying (OR) with analogue network ...
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A pair of terminals exchanging information via a layer of parallel relay nodes under slow fading is considered. Two protocols are proposed based on the combination of opportunistic relaying (OR) with analogue network coding (ANC), named ORANC, or with digital network coding (DNC), named ORDNC, respectively. Two schemes/versions of ORDNC, including 2-phase ORDNC (2P-ORDNC) and 3-phase ORDNC (3P-ORDNC) are proposed. Their outage performances are investigated. ORANC and 2P-ORDNC are proved to achieve optimal diversity-multiplexing tradeoff (DMT), whereas 3P-ORDNC is proved to be suboptimal. However, from diversity viewpoint only, all the above schemes are proven to achieve full diversity order. Simulation results verify the analysis, and show that 3P-ORDNC and ORANC shows advantage at low-and high-data rate regions, respectively.
Active networks are network architectures with processors that are capable of executing code carried by the packets passing through them. A critical network management concern is the optimization of such networks and ...
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Active networks are network architectures with processors that are capable of executing code carried by the packets passing through them. A critical network management concern is the optimization of such networks and tight bounds on their performance serve as useful design benchmarks. A new bound on communication rates is developed that applies to network coding, which is a promising active network application that has processors transmit packets that are general functions, for example a bit-wise XOR, of selected received packets. The bound generalizes an edge-cut bound on routing rates by progressively removing edges from the network graph and checking whether certain strengthened d-separation conditions are satisfied. The bound improves on the cut-set bound and its efficacy is demonstrated by showing that routing is rate-optimal for some commonly cited examples in the networking literature.
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