Journal ArticleDOI
Network information flow
TLDR
This work reveals that it is in general not optimal to regard the information to be multicast as a "fluid" which can simply be routed or replicated, and by employing coding at the nodes, which the work refers to as network coding, bandwidth can in general be saved.Abstract:
We introduce a new class of problems called network information flow which is inspired by computer network applications. Consider a point-to-point communication network on which a number of information sources are to be multicast to certain sets of destinations. We assume that the information sources are mutually independent. The problem is to characterize the admissible coding rate region. This model subsumes all previously studied models along the same line. We study the problem with one information source, and we have obtained a simple characterization of the admissible coding rate region. Our result can be regarded as the max-flow min-cut theorem for network information flow. Contrary to one's intuition, our work reveals that it is in general not optimal to regard the information to be multicast as a "fluid" which can simply be routed or replicated. Rather, by employing coding at the nodes, which we refer to as network coding, bandwidth can in general be saved. This finding may have significant impact on future design of switching systems.read more
Citations
More filters
Proceedings ArticleDOI
Network coding for efficient communication in extreme networks
Jörg Widmer,Jean-Yves Le Boudec +1 more
TL;DR: A communication algorithm is proposed that significantly reduces the overhead of probabilistic routing algorithms, making it a suitable building block for a delay-tolerant network architecture and shows by simulation that this algorithm achieves the reliability and robustness of flooding at a small fraction of the overhead.
Journal ArticleDOI
Insufficiency of linear coding in network information flow
TL;DR: It is shown that the network coding capacity of this counterexample network is strictly greater than the maximum linear coding capacity over any finite field, so the network is not even asymptotically linearly solvable.
The Importance of Being Opportunistic: Practical Network Coding for Wireless Environments
TL;DR: The results show that COPE substantially improves the network throughput, and as the number of flows and the contention level increases, COPE’s throughput becomes many times higher than current 802.11 mesh networks.
Journal ArticleDOI
Capacity of the Gaussian Two-Way Relay Channel to Within ${1\over 2}$ Bit
TL;DR: An achievable scheme composed of nested lattice codes for the uplink and structured binning for the downlink based on a three-stage lattice partition chain, which is a key ingredient for producing the best gap-to-capacity results to date.
Proceedings ArticleDOI
Wireless diversity through network coding
TL;DR: The results show that network-coded DAS leads to better diversity performance as compared to conventional DAS, at a lower hardware cost and higher spectral efficiency.
References
More filters
Book
Elements of information theory
Thomas M. Cover,Joy A. Thomas +1 more
TL;DR: The author examines the role of entropy, inequality, and randomness in the design of codes and the construction of codes in the rapidly changing environment.
Journal ArticleDOI
Factor graphs and the sum-product algorithm
TL;DR: A generic message-passing algorithm, the sum-product algorithm, that operates in a factor graph, that computes-either exactly or approximately-various marginal functions derived from the global function.
Journal ArticleDOI
Noiseless coding of correlated information sources
David Slepian,Jack K. Wolf +1 more
TL;DR: The minimum number of bits per character R_X and R_Y needed to encode these sequences so that they can be faithfully reproduced under a variety of assumptions regarding the encoders and decoders is determined.
Journal ArticleDOI
Linear network coding
TL;DR: This work forms this multicast problem and proves that linear coding suffices to achieve the optimum, which is the max-flow from the source to each receiving node.
Journal ArticleDOI
Achievable rates for multiple descriptions
Abbas El Gamal,Thomas M. Cover +1 more
TL;DR: These rates are shown to be optimal for deterministic distortion measures for random variables and Shannon mutual information.