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\n\n \n \n I Safaka; C. Fragouli; K. Argyraki; and S. Diggavi.\n\n\n \n \n \n \n Exchanging pairwise secrets efficiently.\n \n \n \n\n\n \n\n\n\n In
INFOCOM, 2013 Proceedings IEEE, pages 2265-2273, April 2013. \n
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@inproceedings{6567030,\n abstract = {We consider the problem where a group of wireless nodes, connected to the same broadcast domain, want to create pairwise secrets, in the presence of an adversary Eve, who tries to listen in and steal these secrets. Existing solutions assume that Eve cannot perform certain computations (e.g., large-integer factorization) in useful time. We ask the question: can we solve this problem without assuming anything about Eve's computational capabilities? We propose a simple secret-agreement protocol, where the wireless nodes keep exchanging bits until they have agreed on pairwise secrets that Eve cannot reconstruct with very high probability. Our protocol relies on Eve's limited network presence (the fact that she cannot be located at an arbitrary number of points in the network at the same time), but assumes nothing about her computational capabilities. We formally show that, under standard theoretical assumptions, our protocol is information-theoretically secure (it leaks zero information to Eve about the secrets). Using a small wireless testbed of smart-phones, we provide experimental evidence that it is feasible for 5 nodes to create thousands of secret bits per second, with their secrecy being independent from the adversary's capabilities.},\n author = {Safaka, I and Fragouli, C. and Argyraki, K. and Diggavi, S.},\n booktitle = {INFOCOM, 2013 Proceedings IEEE},\n doi = {10.1109/INFCOM.2013.6567030},\n file = {:papers:exchanging_secrets.pdf},\n issn = {0743-166X},\n month = {April},\n pages = {2265-2273},\n tags = {conf,WiNetSec,IT},\n title = {Exchanging pairwise secrets efficiently},\n type = {4},\n year = {2013}\n}\n\n
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\n We consider the problem where a group of wireless nodes, connected to the same broadcast domain, want to create pairwise secrets, in the presence of an adversary Eve, who tries to listen in and steal these secrets. Existing solutions assume that Eve cannot perform certain computations (e.g., large-integer factorization) in useful time. We ask the question: can we solve this problem without assuming anything about Eve's computational capabilities? We propose a simple secret-agreement protocol, where the wireless nodes keep exchanging bits until they have agreed on pairwise secrets that Eve cannot reconstruct with very high probability. Our protocol relies on Eve's limited network presence (the fact that she cannot be located at an arbitrary number of points in the network at the same time), but assumes nothing about her computational capabilities. We formally show that, under standard theoretical assumptions, our protocol is information-theoretically secure (it leaks zero information to Eve about the secrets). Using a small wireless testbed of smart-phones, we provide experimental evidence that it is feasible for 5 nodes to create thousands of secret bits per second, with their secrecy being independent from the adversary's capabilities.\n
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\n\n \n \n L. Czap; V.M. Prabhakaran; S. Diggavi; and C. Fragouli.\n\n\n \n \n \n \n Securing broadcast against dishonest receivers.\n \n \n \n\n\n \n\n\n\n In
Network Coding (NetCod), 2013 International Symposium on, pages 1-6, June 2013. \n
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@inproceedings{6570819,\n abstract = {Consider a sender, Alice, who wants to transmit private messages to two receivers, Bob and Calvin, using unreliable wireless broadcast transmissions and short public feedback from Bob and Calvin. In [1], we assumed that Bob and Calvin provide honest feedback, and characterized the secure capacity region of the private messages under the requirement that Bob and Calvin do not learn each other's message. In this paper, we assume that Bob (or Calvin) may provide dishonest feedback; or even control the input message distributions, as is commonly assumed in cryptography literature. We characterize the capacity region in the case of dishonest adversaries, as well as an achievable region for the case when the adversary has complete control on the distribution of the messages. We also design polynomial time protocols for both cases, that rely on the use of coding techniques to mix and secure the private messages. As a side result, we define an extended notion of semantic security for this problem and using a similar approach to [2], we show the equivalence of different security notions.},\n author = {Czap, L. and Prabhakaran, V.M. and Diggavi, S. and Fragouli, C.},\n booktitle = {Network Coding (NetCod), 2013 International Symposium on},\n doi = {10.1109/NetCod.2013.6570819},\n file = {:papers:securing_bc.pdf},\n month = {June},\n pages = {1-6},\n tags = {conf,WiNetSec,IT},\n title = {Securing broadcast against dishonest receivers},\n type = {4},\n year = {2013}\n}\n\n
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\n Consider a sender, Alice, who wants to transmit private messages to two receivers, Bob and Calvin, using unreliable wireless broadcast transmissions and short public feedback from Bob and Calvin. In [1], we assumed that Bob and Calvin provide honest feedback, and characterized the secure capacity region of the private messages under the requirement that Bob and Calvin do not learn each other's message. In this paper, we assume that Bob (or Calvin) may provide dishonest feedback; or even control the input message distributions, as is commonly assumed in cryptography literature. We characterize the capacity region in the case of dishonest adversaries, as well as an achievable region for the case when the adversary has complete control on the distribution of the messages. We also design polynomial time protocols for both cases, that rely on the use of coding techniques to mix and secure the private messages. As a side result, we define an extended notion of semantic security for this problem and using a similar approach to [2], we show the equivalence of different security notions.\n
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\n\n \n \n I-Hsiang Wang; and S. Diggavi.\n\n\n \n \n \n \n Interference channels with bursty traffic and delayed feedback.\n \n \n \n\n\n \n\n\n\n In
Signal Processing Advances in Wireless Communications (SPAWC), 2013 IEEE 14th Workshop on, pages 205-209, June 2013. \n
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@inproceedings{6612041,\n abstract = {In this paper we study interference management in wireless networks with bursty user traffic. In each time slot, whether a user is on or off for transmission is governed by its own Bernoulli random state. At each transmitter, the states of activities of other users are only available via feedback. We investigate a canonical two-user bursty Gaussian interference channel (IC) with three different feedback models: (1) no feedback, (2) delayed state feedback, and (3) channel output feedback. In all three cases, we characterize the capacity region of the bursty Gaussian IC to within a bounded gap. It turns out that the near-optimal transmit strategies in the non-bursty IC suffice to establish the approximate characterization of capacity in all three cases. In other words, traffic burstiness does not change the high-SNR optimality of the schemes as long as receivers keep track of user activities. Moreover, the capacity region with delayed state feedback is within a bounded gap to that without feedback, and therefore delayed state feedback does not provide significant improvement at high SNR.},\n author = {I-Hsiang Wang and Diggavi, S.},\n booktitle = {Signal Processing Advances in Wireless Communications (SPAWC), 2013 IEEE 14th Workshop on},\n doi = {10.1109/SPAWC.2013.6612041},\n file = {:papers:bursty_ic_spawc.pdf},\n issn = {1948-3244},\n month = {June},\n pages = {205-209},\n tags = {conf,WiIntMgmt,IT,WiNet},\n title = {Interference channels with bursty traffic and delayed feedback},\n type = {4},\n year = {2013}\n}\n\n
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\n In this paper we study interference management in wireless networks with bursty user traffic. In each time slot, whether a user is on or off for transmission is governed by its own Bernoulli random state. At each transmitter, the states of activities of other users are only available via feedback. We investigate a canonical two-user bursty Gaussian interference channel (IC) with three different feedback models: (1) no feedback, (2) delayed state feedback, and (3) channel output feedback. In all three cases, we characterize the capacity region of the bursty Gaussian IC to within a bounded gap. It turns out that the near-optimal transmit strategies in the non-bursty IC suffice to establish the approximate characterization of capacity in all three cases. In other words, traffic burstiness does not change the high-SNR optimality of the schemes as long as receivers keep track of user activities. Moreover, the capacity region with delayed state feedback is within a bounded gap to that without feedback, and therefore delayed state feedback does not provide significant improvement at high SNR.\n
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\n\n \n \n I-Hsiang Wang; Changho Suh; S. Diggavi; and P. Viswanath.\n\n\n \n \n \n \n Bursty interference channel with feedback.\n \n \n \n\n\n \n\n\n\n In
Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on, pages 21-25, July 2013. \n
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@inproceedings{6620180,\n abstract = {We explore the benefit of feedback for physical layer interference management in wireless networks without centralized upper layer control mechanisms. Lack of coordination in the upper layer could make the interference experienced in the physical layer bursty. To understand how to harness such burstiness with feedback, we investigate a two-user bursty interference channel (IC), where the presence of interference is governed by a Bernoulli random state. We completely characterize the capacity region of the symmetric two-user linear deterministic bursty IC with feedback. The proposed two-phase scheme exploits feedback either for refining the previous interfered reception or for relaying additional information to the legitimate receiver of the other user. Matching outer bounds are derived by novel techniques that take the effect of delayed state information into account. We also use insights from the deterministic case to characterize the approximate symmetric capacity for the symmetric Gaussian bursty IC with feedback in the weak interference regime.},\n author = {I-Hsiang Wang and Changho Suh and Diggavi, S. and Viswanath, P.},\n booktitle = {Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on},\n doi = {10.1109/ISIT.2013.6620180},\n file = {:papers:bursty_ic.pdf},\n issn = {2157-8095},\n month = {July},\n pages = {21-25},\n tags = {conf,WiIntMgmt,IT,WiNet},\n title = {Bursty interference channel with feedback},\n type = {4},\n year = {2013}\n}\n\n
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\n We explore the benefit of feedback for physical layer interference management in wireless networks without centralized upper layer control mechanisms. Lack of coordination in the upper layer could make the interference experienced in the physical layer bursty. To understand how to harness such burstiness with feedback, we investigate a two-user bursty interference channel (IC), where the presence of interference is governed by a Bernoulli random state. We completely characterize the capacity region of the symmetric two-user linear deterministic bursty IC with feedback. The proposed two-phase scheme exploits feedback either for refining the previous interfered reception or for relaying additional information to the legitimate receiver of the other user. Matching outer bounds are derived by novel techniques that take the effect of delayed state information into account. We also use insights from the deterministic case to characterize the approximate symmetric capacity for the symmetric Gaussian bursty IC with feedback in the weak interference regime.\n
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\n\n \n \n C. Karakus; I-Hsiang Wang; and S. Diggavi.\n\n\n \n \n \n \n \n Interference channel with intermittent feedback.\n \n \n \n \n\n\n \n\n\n\n In
Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on, pages 26-30, July 2013. \n
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@inproceedings{6620181,\n abstract = {We investigate how to exploit intermittent feedback for interference management. Focusing on the two-user linear deterministic interference channel, we completely characterize the capacity region. We find that the characterization only depends on the forward channel parameters and the marginal probability distribution of each feedback link. The scheme we propose makes use of block Markov encoding and quantize-map-and-forward at the transmitters, and backward decoding at the receivers. Matching outer bounds are derived based on novel genie-aided techniques. As a consequence, the perfect-feedback capacity can be achieved once the two feedback links are active with large enough probabilities.},\n author = {Karakus, C. and I-Hsiang Wang and Diggavi, S.},\n booktitle = {Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on},\n doi = {10.1109/ISIT.2013.6620181},\n issn = {2157-8095},\n month = {July},\n pages = {26-30},\n tags = {conf,WiIntMgmt,IT,WiNet},\n title = {Interference channel with intermittent feedback},\n type = {4},\n url_arxiv = {http://arxiv.org/abs/1305.3265},\n year = {2013}\n}\n\n
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\n We investigate how to exploit intermittent feedback for interference management. Focusing on the two-user linear deterministic interference channel, we completely characterize the capacity region. We find that the characterization only depends on the forward channel parameters and the marginal probability distribution of each feedback link. The scheme we propose makes use of block Markov encoding and quantize-map-and-forward at the transmitters, and backward decoding at the receivers. Matching outer bounds are derived based on novel genie-aided techniques. As a consequence, the perfect-feedback capacity can be achieved once the two feedback links are active with large enough probabilities.\n
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\n\n \n \n J. Hachem; I-Hsiang Wang; C. Fragouli; and S. Diggavi.\n\n\n \n \n \n \n \n Coding with encoding uncertainty.\n \n \n \n \n\n\n \n\n\n\n In
Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on, pages 276-280, July 2013. \n
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@inproceedings{6620231,\n abstract = {We study the channel coding problem when errors and uncertainty occur in the encoding process. For simplicity we assume the channel between the encoder and the decoder is perfect. Focusing on linear block codes, we model the encoding uncertainty as erasures on the edges in the factor graph of the encoder generator matrix. We first take a worst-case approach and find the maximum tolerable number of erasures for perfect error correction. Next, we take a probabilistic approach and derive a sufficient condition on the rate of a set of codes, such that decoding error probability vanishes as blocklength tends to infinity. In both scenarios, due to the inherent asymmetry of the problem, we derive the results from first principles, which indicates that robustness to encoding errors requires new properties of codes different from classical properties.},\n author = {Hachem, J. and I-Hsiang Wang and Fragouli, C. and Diggavi, S.},\n booktitle = {Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on},\n doi = {10.1109/ISIT.2013.6620231},\n issn = {2157-8095},\n month = {July},\n pages = {276-280},\n tags = {conf,IT},\n title = {Coding with encoding uncertainty},\n type = {4},\n url_arxiv = {http://arxiv.org/abs/1305.3733},\n year = {2013}\n}\n\n
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\n We study the channel coding problem when errors and uncertainty occur in the encoding process. For simplicity we assume the channel between the encoder and the decoder is perfect. Focusing on linear block codes, we model the encoding uncertainty as erasures on the edges in the factor graph of the encoder generator matrix. We first take a worst-case approach and find the maximum tolerable number of erasures for perfect error correction. Next, we take a probabilistic approach and derive a sufficient condition on the rate of a set of codes, such that decoding error probability vanishes as blocklength tends to infinity. In both scenarios, due to the inherent asymmetry of the problem, we derive the results from first principles, which indicates that robustness to encoding errors requires new properties of codes different from classical properties.\n
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\n\n \n \n S. Mishra; C. Fragouli; V. Prabhakaran; and S. Diggavi.\n\n\n \n \n \n \n \n Using feedback for secrecy over graphs.\n \n \n \n \n\n\n \n\n\n\n In
Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on, pages 2399-2403, July 2013. \n
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@inproceedings{6620656,\n abstract = {We study the problem of secure message multicasting over graphs in the presence of a passive (node) adversary who tries to eavesdrop in the network. We show that use of feedback, facilitated through the existence of cycles or undirected edges, enables higher rates than possible in directed acyclic graphs of the same mincut. We demonstrate this using code constructions for canonical combination networks (CCNs). We also provide general outer bounds as well as schemes for node adversaries over CCNs.},\n author = {Mishra, S. and Fragouli, C. and Prabhakaran, V. and Diggavi, S.},\n booktitle = {Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on},\n doi = {10.1109/ISIT.2013.6620656},\n issn = {2157-8095},\n month = {July},\n pages = {2399-2403},\n tags = {conf,WiNetSec,IT},\n title = {Using feedback for secrecy over graphs},\n type = {4},\n url_arxiv = {http://arxiv.org/abs/1305.3051},\n year = {2013}\n}\n\n
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\n We study the problem of secure message multicasting over graphs in the presence of a passive (node) adversary who tries to eavesdrop in the network. We show that use of feedback, facilitated through the existence of cycles or undirected edges, enables higher rates than possible in directed acyclic graphs of the same mincut. We demonstrate this using code constructions for canonical combination networks (CCNs). We also provide general outer bounds as well as schemes for node adversaries over CCNs.\n
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\n\n \n \n S.S. Bidokhti; V.M. Prabhakaran; and S.N. Diggavi.\n\n\n \n \n \n \n A block Markov encoding scheme for broadcasting nested message sets.\n \n \n \n\n\n \n\n\n\n In
Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on, pages 2975-2979, July 2013. \n
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@inproceedings{6620771,\n abstract = {Encoding schemes for broadcasting two nested message sets are studied. We start with a simple class of deterministic broadcast channels for which (variants of) linear superposition coding are optimal in several cases [1], [2]. Such schemes are sub-optimal in general, and we propose a block Markov encoding scheme which achieves (for some deterministic channels) rates not achievable by the previous schemes in [1], [2]. We adapt this block Markov encoding scheme to general broadcast channels, and show that it achieves a rate-region which includes the previously known rate-regions1.},\n author = {Bidokhti, S.S. and Prabhakaran, V.M. and Diggavi, S.N.},\n booktitle = {Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on},\n doi = {10.1109/ISIT.2013.6620771},\n file = {:papers:bme_broadcast.pdf},\n issn = {2157-8095},\n month = {July},\n pages = {2975-2979},\n tags = {conf,IT},\n title = {A block Markov encoding scheme for broadcasting nested message sets},\n type = {4},\n year = {2013}\n}\n\n
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\n Encoding schemes for broadcasting two nested message sets are studied. We start with a simple class of deterministic broadcast channels for which (variants of) linear superposition coding are optimal in several cases [1], [2]. Such schemes are sub-optimal in general, and we propose a block Markov encoding scheme which achieves (for some deterministic channels) rates not achievable by the previous schemes in [1], [2]. We adapt this block Markov encoding scheme to general broadcast channels, and show that it achieves a rate-region which includes the previously known rate-regions1.\n
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\n\n \n \n L. Czap; V.M. Prabhakaran; S. Diggavi; and C. Fragouli.\n\n\n \n \n \n \n Exploiting common randomness: A resource for network secrecy.\n \n \n \n\n\n \n\n\n\n In
Information Theory Workshop (ITW), 2013 IEEE, pages 1-5, Sept 2013. \n
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@inproceedings{6691232,\n abstract = {We investigate the problem of secure communication in a simple network with three communicating parties, two distributed sources who communicate over orthogonal channels to one destination node. The cooperation between the sources is restricted to a rate limited common random source they both observe. The communication channels are erasure channels with strictly causal channel state information of the destination available publicly. A passive adversary is present in the system eavesdropping on any one of the channels. We design a linear scheme that ensures secrecy against the eavesdropper. By deriving an outer bound for the problem we prove that the scheme is optimal in certain special cases.},\n author = {Czap, L. and Prabhakaran, V.M. and Diggavi, S. and Fragouli, C.},\n booktitle = {Information Theory Workshop (ITW), 2013 IEEE},\n doi = {10.1109/ITW.2013.6691232},\n file = {:papers:common_randomness.pdf},\n month = {Sept},\n pages = {1-5},\n tags = {conf,WiNetSec,IT},\n title = {Exploiting common randomness: A resource for network secrecy},\n type = {4},\n year = {2013}\n}\n\n
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\n We investigate the problem of secure communication in a simple network with three communicating parties, two distributed sources who communicate over orthogonal channels to one destination node. The cooperation between the sources is restricted to a rate limited common random source they both observe. The communication channels are erasure channels with strictly causal channel state information of the destination available publicly. A passive adversary is present in the system eavesdropping on any one of the channels. We design a linear scheme that ensures secrecy against the eavesdropper. By deriving an outer bound for the problem we prove that the scheme is optimal in certain special cases.\n
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\n\n \n \n C. Karakus; I-Hsiang Wang; and S. Diggavi.\n\n\n \n \n \n \n An achievable rate region for Gaussian interference channel with intermittent feedback.\n \n \n \n\n\n \n\n\n\n In
Communication, Control, and Computing (Allerton), 2013 51st Annual Allerton Conference on, pages 203-210, Oct 2013. \n
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@inproceedings{6736525,\n abstract = {We consider the two-user Gaussian interference channel with intermittent channel output feedback. We derive an achievable rate region that corresponds to the capacity region of the linear deterministic version of the problem. The result shows that passive and unreliable feedback can be harnessed to provide multiplicative capacity gain in Gaussian interference channels. In contrast to other schemes developed for interference channel with feedback, our achievable scheme makes use of quantize-map-and-forward to relay the information obtained through feedback, performs forward decoding, and does not use structured codes. We find that when the feedback links are active with sufficiently large probabilities, the perfect feedback sum-capacity is achieved to within a constant gap.},\n author = {Karakus, C. and I-Hsiang Wang and Diggavi, S.},\n booktitle = {Communication, Control, and Computing (Allerton), 2013 51st Annual Allerton Conference on},\n doi = {10.1109/Allerton.2013.6736525},\n file = {:papers:ach_gicifb.pdf},\n month = {Oct},\n pages = {203-210},\n tags = {conf,WiIntMgmt,IT,WiNet,WNIF},\n title = {An achievable rate region for Gaussian interference channel with intermittent feedback},\n type = {4},\n year = {2013}\n}\n\n
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\n We consider the two-user Gaussian interference channel with intermittent channel output feedback. We derive an achievable rate region that corresponds to the capacity region of the linear deterministic version of the problem. The result shows that passive and unreliable feedback can be harnessed to provide multiplicative capacity gain in Gaussian interference channels. In contrast to other schemes developed for interference channel with feedback, our achievable scheme makes use of quantize-map-and-forward to relay the information obtained through feedback, performs forward decoding, and does not use structured codes. We find that when the feedback links are active with sufficiently large probabilities, the perfect feedback sum-capacity is achieved to within a constant gap.\n
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\n\n \n \n L. Czap; C. Fragouli; V.M. Prabhakaran; and S. Diggavi.\n\n\n \n \n \n \n Secure network coding with erasures and feedback.\n \n \n \n\n\n \n\n\n\n In
Communication, Control, and Computing (Allerton), 2013 51st Annual Allerton Conference on, pages 1517-1524, Oct 2013. \n
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@inproceedings{6736707,\n abstract = {Secure network coding assumes that the underlying network links are lossless, thus it can be applied over lossy networks after channel error correction. Yet it is well known that channel losses, such as packet erasures, can be constructively used for secrecy over a link. We address here the challenge of extending these results for arbitrary networks. We provide achievability schemes over erasure networks with feedback, that outperform the alternative approach of channel error correction followed by secure message transmission separation. We derive outer bounds on the securely achievable rate and as a consequence we show optimality of our proposed scheme in some special cases.},\n author = {Czap, L. and Fragouli, C. and Prabhakaran, V.M. and Diggavi, S.},\n booktitle = {Communication, Control, and Computing (Allerton), 2013 51st Annual Allerton Conference on},\n doi = {10.1109/Allerton.2013.6736707},\n file = {:papers:secure_netcod.pdf},\n month = {Oct},\n pages = {1517-1524},\n tags = {conf,WiNetSec,IT},\n title = {Secure network coding with erasures and feedback},\n type = {4},\n year = {2013}\n}\n\n
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\n Secure network coding assumes that the underlying network links are lossless, thus it can be applied over lossy networks after channel error correction. Yet it is well known that channel losses, such as packet erasures, can be constructively used for secrecy over a link. We address here the challenge of extending these results for arbitrary networks. We provide achievability schemes over erasure networks with feedback, that outperform the alternative approach of channel error correction followed by secure message transmission separation. We derive outer bounds on the securely achievable rate and as a consequence we show optimality of our proposed scheme in some special cases.\n
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\n\n \n \n A Sahai; S. Diggavi; and A Sabharwal.\n\n\n \n \n \n \n On uplink/downlink full-duplex networks.\n \n \n \n\n\n \n\n\n\n In
Signals, Systems and Computers, 2013 Asilomar Conference on, pages 14-18, Nov 2013. \n
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@inproceedings{6810219,\n abstract = {Recent results in wireless full-duplex promise rate gains over the half-duplex counterpart when two nodes exchange messages with each other. However, when multiple full-duplex nodes operate simultaneously, the resulting network has increased internode interference compared to the half-duplex counterpart. The increased internode interference can potentially limit the rate gain achievable due to introduction of full-duplex capability. In this paper, we present new interference management strategies tha handle internode interference for full-duplex enabled network and achieve rate gains over its half-duplex counterpart.},\n author = {Sahai, A and Diggavi, S. and Sabharwal, A},\n booktitle = {Signals, Systems and Computers, 2013 Asilomar Conference on},\n doi = {10.1109/ACSSC.2013.6810219},\n file = {:papers:asilomar_ul_dl_fd.pdf},\n month = {Nov},\n pages = {14-18},\n tags = {conf,WiIntMgmt,IT},\n title = {On uplink/downlink full-duplex networks},\n type = {4},\n year = {2013}\n}\n\n
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\n Recent results in wireless full-duplex promise rate gains over the half-duplex counterpart when two nodes exchange messages with each other. However, when multiple full-duplex nodes operate simultaneously, the resulting network has increased internode interference compared to the half-duplex counterpart. The increased internode interference can potentially limit the rate gain achievable due to introduction of full-duplex capability. In this paper, we present new interference management strategies tha handle internode interference for full-duplex enabled network and achieve rate gains over its half-duplex counterpart.\n
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\n\n \n \n Katerina Argyraki; Suhas Diggavi; Melissa Duarte; Christina Fragouli; Marios Gatzianas; and Panagiotis Kostopoulos.\n\n\n \n \n \n \n Creating secrets out of erasures.\n \n \n \n\n\n \n\n\n\n In
Proceedings of the 19th annual international conference on Mobile computing & networking, pages 429–440, Sep 2013. ACM\n
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@inproceedings{argyraki2013creating,\n abstract = {Current security systems often rely on the adversary's computational limitations. Wireless networks offer the opportunity for a different, complementary kind of security, which relies on the adversary's limited network presence (i.e., that the adversary cannot be located at many different points in the network at the same time). We present a system that leverages this opportunity to enable n wireless nodes to create a shared secret S, in a way that an eavesdropper, Eve, obtains very little information on S. Our system consists of two steps: (1) The nodes transmit packets following a special pattern, such that Eve learns very little about a given fraction of the transmitted packets. This is achieved through a combination of beam forming (from many different sources) and wiretap codes. (2) The nodes participate in a protocol that reshuffles the information known to each node, such that the nodes end up sharing a secret that Eve knows very little about. Our protocol is easily implementable in existing wireless devices and scales well with the number of nodes; these properties are achieved through a combination of public feedback, broadcasting, and network coding. We evaluate our system through a 5-node testbed. We demonstrate that a group of wireless nodes can generate thousands of new shared secret bits per second, with their secrecy being independent of the adversary's computational capabilities.},\n author = {Argyraki, Katerina and Diggavi, Suhas and Duarte, Melissa and Fragouli, Christina and Gatzianas, Marios and Kostopoulos, Panagiotis},\n booktitle = {Proceedings of the 19th annual international conference on Mobile computing \\& networking},\n file = {:papers:creating_secrets.pdf},\n month = {Sep},\n organization = {ACM},\n pages = {429--440},\n tags = {conf,WiNetSec,IT},\n title = {Creating secrets out of erasures},\n type = {4},\n year = {2013}\n}\n\n
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\n Current security systems often rely on the adversary's computational limitations. Wireless networks offer the opportunity for a different, complementary kind of security, which relies on the adversary's limited network presence (i.e., that the adversary cannot be located at many different points in the network at the same time). We present a system that leverages this opportunity to enable n wireless nodes to create a shared secret S, in a way that an eavesdropper, Eve, obtains very little information on S. Our system consists of two steps: (1) The nodes transmit packets following a special pattern, such that Eve learns very little about a given fraction of the transmitted packets. This is achieved through a combination of beam forming (from many different sources) and wiretap codes. (2) The nodes participate in a protocol that reshuffles the information known to each node, such that the nodes end up sharing a secret that Eve knows very little about. Our protocol is easily implementable in existing wireless devices and scales well with the number of nodes; these properties are achieved through a combination of public feedback, broadcasting, and network coding. We evaluate our system through a 5-node testbed. We demonstrate that a group of wireless nodes can generate thousands of new shared secret bits per second, with their secrecy being independent of the adversary's computational capabilities.\n
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\n\n \n \n Melissa Duarte; Ayan Sengupta; Siddhartha Brahma; Christina Fragouli; and Suhas Diggavi.\n\n\n \n \n \n \n Quantize-map-forward (QMF) relaying: an experimental study.\n \n \n \n\n\n \n\n\n\n In
Proceedings of the fourteenth ACM international symposium on Mobile ad hoc networking and computing, pages 227–236, Jul 2013. ACM\n
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@inproceedings{duarte2013quantize,\n abstract = {We present the design and experimental evaluation of a wireless system that exploits relaying in the context of WiFi. We opt for WiFi given its popularity and wide spread use for a number of applications, such as smart homes. Our testbed consists of three nodes, a source, a relay and a destination, that operate using the physical layer procedures of IEEE802.11. We deploy three main competing strategies that have been proposed for relaying, Decode-and-Forward (DF), Amplify-and-Forward (AF) and Quantize-Map-Forward (QMF). QMF is the most recently introduced of the three, and although it was shown in theory to approximately achieve the capacity of arbitrary wireless networks, its performance in practice had not been evaluated. We present in this work experimental results---to the best of our knowledge, the first ones---that compare QMF, AF and DF in a realistic indoor setting. We find that QMF is a competitive scheme to the other two, offering in some cases up to 12\\% throughput benefits and up to 60\\% improvement in frame error-rates over the next best scheme.},\n author = {Duarte, Melissa and Sengupta, Ayan and Brahma, Siddhartha and Fragouli, Christina and Diggavi, Suhas},\n booktitle = {Proceedings of the fourteenth ACM international symposium on Mobile ad hoc networking and computing},\n file = {:papers:qmf_experimental.pdf},\n month = {Jul},\n organization = {ACM},\n pages = {227--236},\n tags = {conf,WiNet,WiNetInfFlow},\n title = {Quantize-map-forward (QMF) relaying: an experimental study},\n type = {4},\n year = {2013}\n}\n\n
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\n We present the design and experimental evaluation of a wireless system that exploits relaying in the context of WiFi. We opt for WiFi given its popularity and wide spread use for a number of applications, such as smart homes. Our testbed consists of three nodes, a source, a relay and a destination, that operate using the physical layer procedures of IEEE802.11. We deploy three main competing strategies that have been proposed for relaying, Decode-and-Forward (DF), Amplify-and-Forward (AF) and Quantize-Map-Forward (QMF). QMF is the most recently introduced of the three, and although it was shown in theory to approximately achieve the capacity of arbitrary wireless networks, its performance in practice had not been evaluated. We present in this work experimental results—to the best of our knowledge, the first ones—that compare QMF, AF and DF in a realistic indoor setting. We find that QMF is a competitive scheme to the other two, offering in some cases up to 12% throughput benefits and up to 60% improvement in frame error-rates over the next best scheme.\n
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\n\n \n \n Achaleshwar Sahai; Suhas Diggavi; and Ashutosh Sabharwal.\n\n\n \n \n \n \n On degrees-of-freedom of full-duplex uplink/downlink channel.\n \n \n \n\n\n \n\n\n\n In
Information Theory Workshop (ITW), 2013 IEEE, pages 1–5, Sep 2013. IEEE\n
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@inproceedings{sahai2013degrees,\n abstract = {Feasibility of full-duplex opens up the possibility of applying it to cellular networks to operate uplink and downlink simultaneously for multiple users. However, simultaneous operation of uplink and downlink poses a new challenge of intra-cell inter-node interference. In this paper, we identify scenarios where inter-node interference can be managed to provide significant gain in degrees of freedom over the conventional half-duplex cellular design.},\n author = {Sahai, Achaleshwar and Diggavi, Suhas and Sabharwal, Ashutosh},\n booktitle = {Information Theory Workshop (ITW), 2013 IEEE},\n file = {:papers:fd_ul_dl.pdf},\n month = {Sep},\n organization = {IEEE},\n pages = {1--5},\n tags = {conf,WiIntMgmt,IT,WiNet},\n title = {On degrees-of-freedom of full-duplex uplink/downlink channel},\n type = {4},\n year = {2013}\n}\n\n
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\n Feasibility of full-duplex opens up the possibility of applying it to cellular networks to operate uplink and downlink simultaneously for multiple users. However, simultaneous operation of uplink and downlink poses a new challenge of intra-cell inter-node interference. In this paper, we identify scenarios where inter-node interference can be managed to provide significant gain in degrees of freedom over the conventional half-duplex cellular design.\n
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\n\n \n \n I.-H. Wang; and S.N. Diggavi.\n\n\n \n \n \n \n Managing bursty interference with feedback.\n \n \n \n\n\n \n\n\n\n In
IEEE Information Theory Workshop (ITW) 2013, Sep 2013. \n
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@inproceedings{wangdiggavi13,\n author = {Wang, I.-H. and Diggavi, S.N.},\n booktitle = {IEEE Information Theory Workshop (ITW) 2013},\n month = {Sep},\n tags = {conf,IT,WiIntMgmt,WiNet},\n title = {Managing bursty interference with feedback},\n type = {4},\n year = {2013}\n}\n\n
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