Batched sparse(BATS) codes have been proposed for communication through networks with packet loss. BATS codes include a matrix generalization of fountain codes as the outer code and random linear network coding at the...
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Batched sparse(BATS) codes have been proposed for communication through networks with packet loss. BATS codes include a matrix generalization of fountain codes as the outer code and random linear network coding at the intermediate network nodes as the inner code. BATS codes, however, do not possess a universal degree distribution that achieves an optimal rate for any distribution of the transfer matrix ranks. Therefore,it is important to have a fast degree-distribution optimization approach for finite-length BATS codes. In this paper, we propose the concept of batch release probability(BRP), and demonstrate some characteristics of BRPs from the degree distributions achieving nearly optimal performance. Based on these BRP characteristics,we propose a novel degree-distribution optimization approach that achieves the similar decoding performance with a much shorter optimization time, compared with the previous approach. Moreover, the universality of BRPs observed in this paper can further simplify the degree-distribution optimization of BATS codes.
The error control of random network coding has recently received a lot of attention because its solution can increase robustness and reliability of data transmission. To achieve this, additional overhead is needed for...
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The error control of random network coding has recently received a lot of attention because its solution can increase robustness and reliability of data transmission. To achieve this, additional overhead is needed for error correction. In this paper, we design a compressed error and erasure correcting scheme to decrease the additional overhead of error correction. This scheme reduces the computation overhead dramatically by employing an efficient algorithm to detect and delete linearly dependent received packets in the destination node. It also simplifies the hardware operations when the scheme reduces the received matrix Y to form E-k(Y ) instead of E(Y ) in the decoding process. If at most r original packets get combined in k packets of one batch, the payload of one packet can increase from M-k to M-O(rlog(q)k) for the application of compressed code, where M is the packet length. In particular, the decoding complexity of compressed code is O(rm) operations in an extension field F-q(m), which does not enhance the overall decoding complexity of the system. Finally, we also compare our scheme's performance with existing works. The numerical results and analyses illustrate the security and performance of our scheme. Copyright (c) 2011 John Wiley & Sons, Ltd.
The usage of network resources by content providers is commonly governed by Service-Level Agreements (SLA) between the content provider and the network service provider. Resource usage exceeding the limits specified i...
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The usage of network resources by content providers is commonly governed by Service-Level Agreements (SLA) between the content provider and the network service provider. Resource usage exceeding the limits specified in the SLA incurs the content provider additional charges, usually at a higher cost. Hence, the content provider's goal is to provision adequate resources in the SLA based on forecasts of future demand. We study capacity purchasing strategies when the content provider employs network coded multicast as the media delivery mechanism, with uncertainty in its future customer set explicitly taken into consideration. The latter requires the content provider to make capacity provisioning decisions based on market predictions and historical customer usage patterns. The probabilistic element suggests a stochastic optimization approach. We model this problem as a two-stage stochastic optimization problem with recourse. Such optimizations are #P-hard to solve directly, and we design two approximation algorithms for them. The first is a heuristic algorithm that exploits properties unique to network coding, so that only polynomial-time operations are needed. It performs well in general scenarios, but the gap from the optimal solution is not bounded by any constant in the worst case. This motivates our second approach, a sampling algorithm partly inspired from the work of Gupta et al. [2004a]. We employ techniques from duality theory in linear optimization to prove that the sampling algorithm provides a 3-approximation to the stochastic multicast problem. We conduct extensive simulations to illustrate the efficacy of both algorithms, and show that the performance of both is usually within 10% of the optimal solution in practice.
In this paper, we consider the problem of secure communication over wiretap multicast networks. Noticing that network coding renders the intermediate nodes to mix information from different data flows, we propose a se...
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In this paper, we consider the problem of secure communication over wiretap multicast networks. Noticing that network coding renders the intermediate nodes to mix information from different data flows, we propose a secure communication scheme based on cryptographic means and network coding. Specifically, we employ a confidential cryptosystem to encrypt the source message packets, then treat the secret key as a message packet and mix the key with the obtained cryptograms. Furthermore, we can prove that, under suitable conditions, the wiretapper is unable to gain the secret key. Meanwhile, the confidential cryptosystem prohibits the wiretapper from extracting meaningful information from the obtained cryptograms. Our scheme doesn’t need a private channel to transmit the secret key and enables the utilization of network capacity to reach 1 n n .
In this paper, we present a demodulate-and-forward (DMF) protocol for multiuser cooperative transmission scheme with network coding. network coding based on DMF is a promising technique to improve network throughput a...
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In this paper, we present a demodulate-and-forward (DMF) protocol for multiuser cooperative transmission scheme with network coding. network coding based on DMF is a promising technique to improve network throughput and reduce the complexity of hardware and processing delay. For mitigating and evaluating errors at the destinations, a single equivalent channel gain is expressed to evaluate the ends-to-ends (the sources-relay-destinations) channel conditions. We derive and analyze the average bit error probability (BEP) expressions and diversity gain for the DMF cooperative transmission based on network coding over Rayleigh fading channels. Theoretical analysis and numerical evaluation show that the proposed scheme can offer improved BEP and provably collect full diversity at lower hardware cost and higher spectral efficiency.
This paper presents a practical multicast routing, which dynamically transforms a conventional multicast tree into a multicast mesh and increases the opportunities for coding by applying double direction network codin...
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This paper presents a practical multicast routing, which dynamically transforms a conventional multicast tree into a multicast mesh and increases the opportunities for coding by applying double direction network coding scheme. The simulation shows the proposed algorithm is a practical multicast routing, and it has better performances by comparing with ODMRP and MORE-M in terms of coding gain and packet delivery ratio.
Adaptive randomized convolutional network coding (ARCNC) algorithm is proposed to address the field size and unknown topology problems in network coding, by which a large gain is obtained over combination networks. We...
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Adaptive randomized convolutional network coding (ARCNC) algorithm is proposed to address the field size and unknown topology problems in network coding, by which a large gain is obtained over combination networks. We reconsider ARCNC over combination networks in view of the law of large numbers, and prove by Chebyshev inequality that an infinite gain is obtained using ARCNC in combination networks. This is not only an evidence of ARCNC benefits, but also provides a new research tool.
This paper describes how eavesdropping can potentially be restrained by introducing cooperative jamming. A wiretap channel of two-way relay with analog network coding (ANC) is considered, in which a transmitter sends ...
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This paper describes how eavesdropping can potentially be restrained by introducing cooperative jamming. A wiretap channel of two-way relay with analog network coding (ANC) is considered, in which a transmitter sends message to its intended receiver in the presence of a passive eavesdropper and with the help of an active jammer. The eavesdropper, who does not know the interfering message from the cooperative jammer, is confused to extract the useful information. The achievable secrecy rates are given, and by numerical analysis, it can be increased effectively by cooperative jamming. Though it harms the achievable rate of main source-destination channel simultaneously, considering the better improvement of achievable secrecy rate, the loss is valuable and acceptable. And we find a tradeoff scheme between gain of security and loss of efficiency.
Cooperative communication is one of the most efficient ways to improve reliability of wireless links. We introduce linear network coding into multi-user cooperative communication system, and propose a new cooperating ...
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In this paper, we establish an analytical model of probabilistic routing, and propose a network coding based probabilistic routing (NC-PR), in comparison with the traditional probabilistic routing in terms of transmis...
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In this paper, we establish an analytical model of probabilistic routing, and propose a network coding based probabilistic routing (NC-PR), in comparison with the traditional probabilistic routing in terms of transmission delay. Through the indices, we assess the validity of the model. Theoretical analysis results indicate that the model can effectively analyze the performance of probabilistic routing. Comparing with the traditional probabilistic routing, the NC-PR can reduce network transmission delay, increase reliability of network and improve the overall performance of probabilistic routing protocol.
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