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Resilient Network Coding in the Presence of Byzantine Adversaries
"... Network coding substantially increases network throughput. But since it involves mixing of information inside the network, a single corrupted packet generated by a malicious node can end up contaminating all the information reaching a destination, preventing decoding. This paper introduces distribu ..."
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Cited by 169 (32 self)
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Network coding substantially increases network throughput. But since it involves mixing of information inside the network, a single corrupted packet generated by a malicious node can end up contaminating all the information reaching a destination, preventing decoding. This paper introduces distributed polynomial-time rateoptimal network codes that work in the presence of Byzantine nodes. We present algorithms that target adversaries with different attacking capabilities. When the adversary can eavesdrop on all links and jam zO links, our first algorithm achieves a rate of C − 2zO, where C is the network capacity. In contrast, when the adversary has limited eavesdropping capabilities, we provide algorithms that achieve the higher rate of C − zO. Our algorithms attain the optimal rate given the strength of the adversary. They are informationtheoretically secure. They operate in a distributed manner, assume no knowledge of the topology, and can be designed and implemented in polynomial-time. Furthermore, only the source and destination need to be modified; non-malicious nodes inside the network are oblivious to the presence of adversaries and implement a classical distributed network code. Finally, our algorithms work over wired and wireless networks.
Achieving Single Channel, Full Duplex Wireless Communication
"... Co-primary authors This paper discusses the design of a single channel full-duplex wireless transceiver. The design uses a combination of RF and baseband techniques to achieve full-duplexing with minimal effect on link reliability. Experiments on real nodes show the fullduplex prototype achieves med ..."
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Cited by 134 (9 self)
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Co-primary authors This paper discusses the design of a single channel full-duplex wireless transceiver. The design uses a combination of RF and baseband techniques to achieve full-duplexing with minimal effect on link reliability. Experiments on real nodes show the fullduplex prototype achieves median performance that is within 8% of an ideal full-duplexing system. This paper presents Antenna Cancellation, a novel technique for self-interference cancellation. In conjunction with existing RF interference cancellation and digital baseband interference cancellation, antenna cancellation achieves the amount of self-interference cancellation required for full-duplex operation. The paper also discusses potential MAC and network gains with full-duplexing. It suggests ways in which a full-duplex system can solve some important problems with existing wireless systems including hidden terminals, loss of throughput due to congestion, and large end-to-end delays.
Four-Bit Wireless Link Estimation
"... We consider the problem of estimating link quality in an ad-hoc wireless mesh. We argue that estimating links well requires combining information from the network, link, and physical layers. We propose narrow, protocol-independent link estimation interfaces for the layers, which in total provide fou ..."
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Cited by 108 (10 self)
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We consider the problem of estimating link quality in an ad-hoc wireless mesh. We argue that estimating links well requires combining information from the network, link, and physical layers. We propose narrow, protocol-independent link estimation interfaces for the layers, which in total provide four bits of information: 1 from the physical layer, 1 from the link layer, and 2 from the network layer. We present a link estimator design with these interfaces that reduces packet delivery costs by up to 44 % over current approaches and maintains a 99 % delivery ratio over large, multihop testbeds. 1
Wireless Broadcasting Using Network Coding
"... Traditional approaches to transmit information reliably over an error-prone network employ either Forward Error Correction (FEC) or retransmission techniques. In this paper we consider an application of network coding to increase the bandwidth efficiency of reliable broadcast in a wireless network ..."
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Cited by 73 (2 self)
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Traditional approaches to transmit information reliably over an error-prone network employ either Forward Error Correction (FEC) or retransmission techniques. In this paper we consider an application of network coding to increase the bandwidth efficiency of reliable broadcast in a wireless network. In particular, we propose two schemes which employ network coding to reduce the number of retransmissions as a result of packet losses. Our proposed schemes combine different lost packets from different receivers in such a way that multiple receivers are able to recover their lost packets with one transmission by the source. The advantages of the proposed schemes over the traditional wireless broadcast are shown through simulations and theoretical analysis. Specifically, we provide a few results on the retransmission overhead of the proposed schemes under different channel conditions.
Signing a Linear Subspace: Signature Schemes for Network Coding
"... Abstract. Network coding offers increased throughput and improved robustness to random faults in completely decentralized networks. In contrast to traditional routing schemes, however, network coding requires intermediate nodes to modify data packets en route; for this reason, standard signature sch ..."
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Cited by 72 (8 self)
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Abstract. Network coding offers increased throughput and improved robustness to random faults in completely decentralized networks. In contrast to traditional routing schemes, however, network coding requires intermediate nodes to modify data packets en route; for this reason, standard signature schemes are inapplicable and it is a challenge to provide resilience to tampering by malicious nodes. Here, we propose two signature schemes that can be used in conjunction with network coding to prevent malicious modification of data. In particular, our schemes can be viewed as signing linear subspaces in the sense that a signature σ on V authenticates exactly those vectors in V. Our first scheme is homomorphic and has better performance, with both public key size and per-packet overhead being constant. Our second scheme does not rely on random oracles and uses weaker assumptions. We also prove a lower bound on the length of signatures for linear subspaces showing that both of our schemes are essentially optimal in this regard. 1
Optimized Constellations for Two–Way Wireless Relaying with Physical Network Coding
- IEEE JOURNAL OF SELECTED AREAS IN COMMUN.
, 2016
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Symmetric Feedback Capacity of the Gaussian Interference Channel to Within One Bit
"... We characterize the symmetric capacity of the two-user Gaussian interference channel with feedback to within 1 bit/s/Hz. The result makes use of a deterministic model to provide insights into the Gaussian channel. We derive a new outer bound to show that a proposed scheme can achieve the symmetric ..."
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Cited by 67 (5 self)
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We characterize the symmetric capacity of the two-user Gaussian interference channel with feedback to within 1 bit/s/Hz. The result makes use of a deterministic model to provide insights into the Gaussian channel. We derive a new outer bound to show that a proposed scheme can achieve the symmetric capacity to within one bit for all channel parameters. From this result, we show that feedback provides unbounded gain, i.e., the gain becomes arbitrarily large for certain channel parameters. It is a surprising result because feedback has been so far known to provide no gain in memoryless point-to-point channels and only power gain (bounded gain) in the multiple access channels.
Adaptive network coding and scheduling for maximizing througput in wireless networks
- In Proceedings of ACM Mobicom
, 2007
"... Recently, network coding emerged as a promising technol-ogy that can provide significant improvements in through-put and energy efficiency of wireless networks, even for uni-cast communication. Often, network coding schemes are designed as an autonomous layer, independent of the un-derlying Phy and ..."
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Cited by 64 (1 self)
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Recently, network coding emerged as a promising technol-ogy that can provide significant improvements in through-put and energy efficiency of wireless networks, even for uni-cast communication. Often, network coding schemes are designed as an autonomous layer, independent of the un-derlying Phy and MAC capabilities and algorithms. Con-sequently, these schemes are greedy, in the sense that all opportunities of broadcasting combinations of packets are exploited. We demonstrate that this greedy design principle may in fact reduce the network throughput. This begets the need for adaptive network coding schemes. We further show that designing appropriate MAC scheduling algorithms is critical for achieving the throughput gains expected from network coding. In this paper, we propose a general frame-work to develop optimal and adaptive joint network coding and scheduling schemes. Optimality is shown for various Phy and MAC constraints. We apply this framework to two different network coding architectures: COPE, a scheme re-cently proposed in [7], and XOR-Sym, a new scheme we present here. XOR-Sym is designed to achieve a lower im-plementation complexity than that of COPE, and yet to provide similar throughput gains.
On the Index Coding Problem and its Relation to Network Coding and Matroid Theory
"... The index coding problem has recently attracted a significant attention from the research community due to its theoretical significance and applications in wireless ad-hoc networks. An instance of the index coding problem includes a sender that holds a set of information messages X = {x1,..., xk} an ..."
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Cited by 57 (5 self)
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The index coding problem has recently attracted a significant attention from the research community due to its theoretical significance and applications in wireless ad-hoc networks. An instance of the index coding problem includes a sender that holds a set of information messages X = {x1,..., xk} and a set of receivers R. Each receiver ρ = (x,H) in R needs to obtain a message x ∈ X and has prior side information consisting of a subset H of X. The sender uses a noiseless communication channel to broadcast encoding of messages in X to all clients. The objective is to find an encoding scheme that minimizes the number of transmissions required to satisfy the demands of all the receivers. In this paper, we analyze the relation between the index coding problem, the more general network coding problem, and the problem of finding a linear representation of a matroid. In particular, we show that any instance of the network coding and matroid representation problems can be efficiently reduced to an instance of the index coding problem. Our reduction implies that many important properties of the network coding and matroid representation problems carry over to the index coding problem. Specifically, we show that vector linear codes outperform scalar linear index codes and that vector linear codes are insufficient for achieving the optimum number of transmissions.
Reliable physical layer network coding
- PROCEEDINGS OF THE IEEE
, 2011
"... When two or more users in a wireless network transmit simultaneously, their electromagnetic signals are linearly superimposed on the channel. As a result, a receiver that is interested in one of these signals sees the others as unwanted interference. This property of the wireless medium is typicall ..."
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Cited by 54 (5 self)
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When two or more users in a wireless network transmit simultaneously, their electromagnetic signals are linearly superimposed on the channel. As a result, a receiver that is interested in one of these signals sees the others as unwanted interference. This property of the wireless medium is typically viewed as a hindrance to reliable communication over a network. However, using a recently developed coding strategy, interference can in fact be harnessed for network coding. In a wired network, (linear) network coding refers to each intermediate node taking its received packets, computing a linear combination over a finite field, and forwarding the outcome towards the destinations. Then, given an appropriate set of linear combinations, a destination can solve for its desired packets. For certain topologies, this strategy can attain significantly higher throughputs over routing-based strategies. Reliable physical layer network coding takes this idea one step further: using judiciously chosen linear error-correcting codes, intermediate nodes in a wireless network can directly recover linear combinations of the packets from the observed noisy superpositions of transmitted signals. Starting with some simple examples, this survey explores the core ideas behind this new technique and the possibilities it offers for communication over interference-limited wireless networks.
