10,700 research outputs found

    Faster Gossiping in Bidirectional Radio Networks with Large Labels

    Full text link
    We consider unknown ad-hoc radio networks, when the underlying network is bidirectional and nodes can have polynomially large labels. For this model, we present a deterministic protocol for gossiping which takes O(nlg2nlglgn)O(n \lg^2 n \lg \lg n) rounds. This improves upon the previous best result for deterministic gossiping for this model by [Gasienec, Potapov, Pagourtizis, Deterministic Gossiping in Radio Networks with Large labels, ESA (2002)], who present a protocol of round complexity O(nlg3nlglgn)O(n \lg^3 n \lg \lg n) for this problem. This resolves open problem posed in [Gasienec, Efficient gossiping in radio networks, SIROCCO (2009)], who cite bridging gap between lower and upper bounds for this problem as an important objective. We emphasize that a salient feature of our protocol is its simplicity, especially with respect to the previous best known protocol for this problem

    Distributed Deterministic Broadcasting in Uniform-Power Ad Hoc Wireless Networks

    Full text link
    Development of many futuristic technologies, such as MANET, VANET, iThings, nano-devices, depend on efficient distributed communication protocols in multi-hop ad hoc networks. A vast majority of research in this area focus on design heuristic protocols, and analyze their performance by simulations on networks generated randomly or obtained in practical measurements of some (usually small-size) wireless networks. %some library. Moreover, they often assume access to truly random sources, which is often not reasonable in case of wireless devices. In this work we use a formal framework to study the problem of broadcasting and its time complexity in any two dimensional Euclidean wireless network with uniform transmission powers. For the analysis, we consider two popular models of ad hoc networks based on the Signal-to-Interference-and-Noise Ratio (SINR): one with opportunistic links, and the other with randomly disturbed SINR. In the former model, we show that one of our algorithms accomplishes broadcasting in O(Dlog2n)O(D\log^2 n) rounds, where nn is the number of nodes and DD is the diameter of the network. If nodes know a priori the granularity gg of the network, i.e., the inverse of the maximum transmission range over the minimum distance between any two stations, a modification of this algorithm accomplishes broadcasting in O(Dlogg)O(D\log g) rounds. Finally, we modify both algorithms to make them efficient in the latter model with randomly disturbed SINR, with only logarithmic growth of performance. Ours are the first provably efficient and well-scalable, under the two models, distributed deterministic solutions for the broadcast task.Comment: arXiv admin note: substantial text overlap with arXiv:1207.673

    Deterministic Digital Clustering of Wireless Ad Hoc Networks

    Full text link
    We consider deterministic distributed communication in wireless ad hoc networks of identical weak devices under the SINR model without predefined infrastructure. Most algorithmic results in this model rely on various additional features or capabilities, e.g., randomization, access to geographic coordinates, power control, carrier sensing with various precision of measurements, and/or interference cancellation. We study a pure scenario, when no such properties are available. As a general tool, we develop a deterministic distributed clustering algorithm. Our solution relies on a new type of combinatorial structures (selectors), which might be of independent interest. Using the clustering, we develop a deterministic distributed local broadcast algorithm accomplishing this task in O(ΔlogNlogN)O(\Delta \log^*N \log N) rounds, where Δ\Delta is the density of the network. To the best of our knowledge, this is the first solution in pure scenario which is only polylog(n)(n) away from the universal lower bound Ω(Δ)\Omega(\Delta), valid also for scenarios with randomization and other features. Therefore, none of these features substantially helps in performing the local broadcast task. Using clustering, we also build a deterministic global broadcast algorithm that terminates within O(D(Δ+logN)logN)O(D(\Delta + \log^* N) \log N) rounds, where DD is the diameter of the network. This result is complemented by a lower bound Ω(DΔ11/α)\Omega(D \Delta^{1-1/\alpha}), where α>2\alpha > 2 is the path-loss parameter of the environment. This lower bound shows that randomization or knowledge of own location substantially help (by a factor polynomial in Δ\Delta) in the global broadcast. Therefore, unlike in the case of local broadcast, some additional model features may help in global broadcast
    corecore