303,086 research outputs found
Exploiting spontaneous transmissions for broadcasting and leader election in radio networks
We study two fundamental communication primitives: broadcasting and leader election in the classical model of multi-hop radio networks with unknown topology and without collision detection mechanisms. It has been known for almost 20 years that in undirected networks with n nodes and diameter D, randomized broadcasting requires Ω(D log n/D + log2 n) rounds, assuming that uninformed nodes are not allowed to communicate (until they are informed). Only very recently, Haeupler and Wajc (PODC'2016) showed that this bound can be improved for the model with spontaneous transmissions, providing an O(D log n log log n/log D + logO(1) n)-time broadcasting algorithm. In this article, we give a new and faster algorithm that completes broadcasting in O(D log n/log D + logO(1) n) time, succeeding with high probability. This yields the first optimal O(D)-time broadcasting algorithm whenever n is polynomial in D.
Furthermore, our approach can be applied to design a new leader election algorithm that matches the performance of our broadcasting algorithm. Previously, all fast randomized leader election algorithms have used broadcasting as a subroutine and their complexity has been asymptotically strictly larger than the complexity of broadcasting. In particular, the fastest previously known randomized leader election algorithm of Ghaffari and Haeupler (SODA'2013) requires O(D log n/D min {log log n, log n/D} + logO(1) n)-time, succeeding with high probability. Our new algorithm again requires O(D log n/log D + logO(1) n) time, also succeeding with high probability
Economics of Domestic Cultural Content Protection in Broadcasting, The
We analyze the economics of domestic cultural content protection in terrestrial broadcasting, the most widespread policy instrument used in broadcasting. Using the love-of-variety approach, we model a representative consumer deriving utility from broadcasting services net of advertising,and allocating scarce time between consuming the various broadcasting services and leisure. Advertising is a nuisance; it costs time yet brings no utility. Broadcasting is a pure public good; broadcasters make profit in the monopolistic competition environment by bundling advertising with valuable cultural content. We impose a discrete domestic content requirement and then investigate the effects of its marginal changes on consumption of domestic broadcasting. Domestic content requirement may reduce (increase) consumption of domestic programs when consumer's demand is highly elastic (inelastic), the degree of preference for foreign content over domestic content is high (low) and opportunity cost of listening time is high (low). The reduction occurs because the consumer reshuffles her consumption bundle towards leisure away from high domestic-content stations thereby reducing the overall aggregate consumption of broadcasting, and subsequently, the overall aggregate consumption of domestic programs.boradcasting; domestic content; radio; cultural protection
Latency Optimal Broadcasting in Noisy Wireless Mesh Networks
In this paper, we adopt a new noisy wireless network model introduced very
recently by Censor-Hillel et al. in [ACM PODC 2017, CHHZ17]. More specifically,
for a given noise parameter any sender has a probability of
of transmitting noise or any receiver of a single transmission in its
neighborhood has a probability of receiving noise.
In this paper, we first propose a new asymptotically latency-optimal
approximation algorithm (under faultless model) that can complete
single-message broadcasting task in time units/rounds in any
WMN of size and diameter . We then show this diameter-linear
broadcasting algorithm remains robust under the noisy wireless network model
and also improves the currently best known result in CHHZ17 by a
factor.
In this paper, we also further extend our robust single-message broadcasting
algorithm to multi-message broadcasting scenario and show it can broadcast
messages in time rounds. This new robust
multi-message broadcasting scheme is not only asymptotically optimal but also
answers affirmatively the problem left open in CHHZ17 on the existence of an
algorithm that is robust to sender and receiver faults and can broadcast
messages in time rounds.Comment: arXiv admin note: text overlap with arXiv:1705.07369 by other author
An adaptive quasi harmonic broadcasting scheme with optimal bandwidth requirement
The aim of Harmonic Broadcasting protocol is to reduce the bandwidth usage in
video-on-demand service where a video is divided into some equal sized segments
and every segment is repeatedly transmitted over a number of channels that
follows harmonic series for channel bandwidth assignment. As the bandwidth of
channels differs from each other and users can join at any time to these
multicast channels, they may experience a synchronization problem between
download and playback. To deal with this issue, some schemes have been
proposed, however, at the cost of additional or wastage of bandwidth or sudden
extreme bandwidth requirement. In this paper we present an adaptive quasi
harmonic broadcasting scheme (AQHB) which delivers all data segment on time
that is the download and playback synchronization problem is eliminated while
keeping the bandwidth consumption as same as traditional harmonic broadcasting
scheme without cost of any additional or wastage of bandwidth. It also ensures
the video server not to increase the channel bandwidth suddenly that is, also
eliminates the sudden buffer requirement at the client side. We present several
analytical results to exhibit the efficiency of our proposed broadcasting
scheme over the existing ones.Comment: IEEE International Conference on Informatics, Electronics & Vision
(ICIEV), 2013, 6pages, 8 figure
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