In wireless broadcasting systems, lost packets are retransmitted to guarantee the correct reception of each packet. Traditional automatic retransmission request (ARQ) protocol retransmits one packet per slot, which le...
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ISBN:
(纸本)9781479987962
In wireless broadcasting systems, lost packets are retransmitted to guarantee the correct reception of each packet. Traditional automatic retransmission request (ARQ) protocol retransmits one packet per slot, which leads to low spectrum efficiency. In this paper, we propose a Max2-Min network coding based Wireless BroadCasting (WBC) protocol. Specifically, to reduce the overall number of retransmissions, lost packets of different user equipments (UEs) are combined by performing Max2-Min network coding (NC) at the base station. Then, NC combined packets are broadcasted to all the UEs. At each UE, lost packets can be recovered by using the proposed joint network and recursive systematic convolution (RSC) decoder (JNRD). Theoretical analyses and simulation results show that the proposed Max2-Min NC based WBC protocol outperforms traditional NC based WBC protocol on the average number of transmissions performance.
The physical-layer network coding (PNC) has become a hot research topic, since it can potentially reduce the transmission time slots and increase the channel capacity. However, current studies are mainly concentrated ...
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The physical-layer network coding (PNC) has become a hot research topic, since it can potentially reduce the transmission time slots and increase the channel capacity. However, current studies are mainly concentrated on three nodes (two users and one relay) network. This paper considers a specific multiuser network that includes M (M>2) users with one relay, and illustrates the transmission scheme and evaluates its bit error rate (BER), information theoretical capacity and anti-noise performance under AWGN channel. Moreover, 2FSK is considered in the proposed network, since it does not need accurate phase tracking. Simulation results show that its information theoretical capacity would decrease significantly with the number of users in this network increase, however the capacity of the proposed scheme is still better than that of the IEEE802.11 networks.
It is known that network coding helps enhance various performance metrics in networked systems. However, to take advantage of network coding, especially random network coding, low encoding/decoding latency must be gua...
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It is known that network coding helps enhance various performance metrics in networked systems. However, to take advantage of network coding, especially random network coding, low encoding/decoding latency must be guaranteed. In this paper, we introduce a fast random network coding parallelization technique targeting multicore processors.
VANET is a real-time, intelligent transportation network featuring motion patterns limited by roads, diverse transmission data, and frequent topological changes. In the highway scene, the network coding and the roadsi...
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ISBN:
(纸本)9781665432863
VANET is a real-time, intelligent transportation network featuring motion patterns limited by roads, diverse transmission data, and frequent topological changes. In the highway scene, the network coding and the roadside unit are introduced to assist the data transmission in order to solve such problems as single data transmission path and short communication link duration. When the vehicle node transmits data, it will first determine the type of vehicle node at this time, and select the best transmission path as the main path of the encoded data packet according to the relative position information of the vehicle nodes, the difference of the requested content storage nodes, and the vehicle density. The path acts as a secondary path for the transmission of encoded packets. Finally, the routing strategy proposed in this paper is implemented by the opportunistic network simulator ONE simulation. According to the experimental results, the routing strategy proposed in this paper can effectively improve the message delivery rate, reduce the average network delay and network overhead.
network coding in cyclic networks may have better performance than network coding in acyclic networks with regard to the multi-unicast scenarios. Harvey et al. showed that network coding in cyclic networks can be stri...
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ISBN:
(纸本)9781424447848
network coding in cyclic networks may have better performance than network coding in acyclic networks with regard to the multi-unicast scenarios. Harvey et al. showed that network coding in cyclic networks can be strictly better than fractional routing in conservative networks which have widely practical scenarios such as P2P networks. Hence, we motivated investigating how to achieve that better performance of network coding in cyclic networks by a general construction algorithm. Li et al. presented there are four levels for network code in cyclic networks, including basic convolutional network code (BCNC), convolutional dispersion (CD), convolutional broadcast (CB) and convolutional multicast (CM). Subsequently, it is interesting to investigate how to construct all four levels of network coding in cyclic networks. Based on our previous work of construction algorithm of BCNC, we proposed a unified algorithm to construct network coding in cyclic networks using notion of flow set. Our contributions were as follows: (1) we showed insights of the essential difference between two classes(i.e. BCNC and CD/CB/CM) of network codes in cyclic networks. (2) we showed insights how to uniformly handle cycles for these two classes of network codes in cyclic networks by proposing the unified construction algorithm. Here, we used the cycles classifications defined by Barbero et al., including link cycles but flow-acyclic, simple flow cycles and flow knots(simply knots).
For general connections, the problem of finding network codes and optimizing resources for those codes is intrinsically difficult and little is known about its complexity. Most of the existing solutions rely on very r...
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ISBN:
(纸本)9781467364300
For general connections, the problem of finding network codes and optimizing resources for those codes is intrinsically difficult and little is known about its complexity. Most of the existing solutions rely on very restricted classes of network codes in terms of the number of flows allowed to be coded together, and are not entirely distributed. In this paper, we consider a new method for constructing linear network codes for general connections of continuous flows to minimize the total cost of edge use based on mixing. We first formulate the minimum-cost network coding design problem. To solve the optimization problem, we propose two equivalent alternative formulations with discrete mixing and continuous mixing, respectively, and develop distributed algorithms to solve them. Our approach allows fairly general coding across flows and guarantees no greater cost than any solution without inter-flow network coding.
In recent years, content delivery networks (CDN) and Peer-to-Peer (P2P) networks have emerged as two effective paradigms for delivering multimedia contents over the Internet. An important feature in CDN and P2P networ...
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In recent years, content delivery networks (CDN) and Peer-to-Peer (P2P) networks have emerged as two effective paradigms for delivering multimedia contents over the Internet. An important feature in CDN and P2P networks is the data redundancy across multiple servers/peers which enables efficient media delivery. In this paper, we propose a network coding framework for efficient media streaming in either content delivery networks or P2P networks in which, multiple servers/peers are employed to simultaneously stream a video to a single receiver. Unlike previous multi-sender schemes, we show that network coding technique can (a) reduce the redundancy storage, (b) eliminate the need for tight synchronization between the senders, and (c) be integrated easily with TCP. Furthermore, we propose the Hierarchical network coding (HNC) technique to be used with scalable video bit stream to combat bandwidth fluctuation on the Internet. Simulation results demonstrate that our proposed scheme can result in bandwidth saving up to 40% for many cases over the traditional schemes.
Buffer-aided network coding (NC) has been proposed as an effective method to improve retransmission efficiency. In this way, the correctly received undecodable NC combined retransmission packets are waited in the buff...
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ISBN:
(纸本)9781467376884
Buffer-aided network coding (NC) has been proposed as an effective method to improve retransmission efficiency. In this way, the correctly received undecodable NC combined retransmission packets are waited in the buffer for a future network decoding opportunity rather than delete. However, existing buffer-aided approaches fail to consider the buffer status and the latest feedback in the next round of network encoding and therefore are unable to achieve the optimal performance. In this paper, a buffer-aided and weight-based non-orthogonal network coding scheme for wireless broadcasting (BWNNC) has been proposed, wherein the sender makes full use of all the known information to conduct non-orthogonal network coding retransmissions. Simulation results show that our proposed algorithm indeed outperforms previous works in reducing the retransmission times.
Starting from a recently proposed network coding resource optimization method, we discuss the scalability of this solution to larger scale-free topologies that are also characterized by a realistic link loss distribut...
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Starting from a recently proposed network coding resource optimization method, we discuss the scalability of this solution to larger scale-free topologies that are also characterized by a realistic link loss distribution which we derive from measurements. We sketch a possibility of designing a network coding aware multicast routing scheme for hierarchical networks.
Present-day and future network protocols that include and implement Forward Error Correction are configurable by internal parameters, typically incorporating expert knowledge to set *** introduce a framework to system...
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ISBN:
(数字)9781728150895
ISBN:
(纸本)9781728150901
Present-day and future network protocols that include and implement Forward Error Correction are configurable by internal parameters, typically incorporating expert knowledge to set *** introduce a framework to systematically, objectively and efficiently determine parameters for Random Linear network Codes (RLNC). Our approach uses an unbiased, consistent simulator in an optimization loop and utilizes a customizable, powerful and extendable parametric loss function. This allows to tailor existing protocols to various use cases, including ultra reliable, low latency communication (URLLC) codes. Successful configurations exploring the search space are under evolutionary pressure and written into a database for instant retrieval. We demonstrate three examples, Full Vector coding, tail RLNC, and PACE with different focus for each.
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