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139
Minimumenergy broadcast in allwireless networks: Npcompleteness and distribution
 In Proc. of ACM MobiCom
, 2002
"... In allwireless networks a crucial problem is to minimize energy consumption, as in most cases the nodes are batteryoperated. We focus on the problem of poweroptimal broadcast, for which it is well known that the broadcast nature of the radio transmission can be exploited to optimize energy consump ..."
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Cited by 177 (2 self)
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In allwireless networks a crucial problem is to minimize energy consumption, as in most cases the nodes are batteryoperated. We focus on the problem of poweroptimal broadcast, for which it is well known that the broadcast nature of the radio transmission can be exploited to optimize energy consumption. Several authors have conjectured that the problem of poweroptimal broadcast is NPcomplete. We provide here a formal proof, both for the general case and for the geometric one; in the former case, the network topology is represented by a generic graph with arbitrary weights, whereas in the latter a Euclidean distance is considered. We then describe a new heuristic, Embedded Wireless Multicast Advantage. We show that it compares well with other proposals and we explain how it can be distributed. Categories and Subject Descriptors
Minimum energy mobile wireless networks revisited
 In IEEE International Conference on Communications (ICC
, 2001
"... Energy conservation is a critical issue in designing wireless ad hoc networks, as the nodes are powered by batteries only. Given a set of wireless network nodes, the directed weighted transmission graph Gt has an edge uv if and only if node v is in the transmission range of node u and the weight of ..."
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Cited by 170 (6 self)
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Energy conservation is a critical issue in designing wireless ad hoc networks, as the nodes are powered by batteries only. Given a set of wireless network nodes, the directed weighted transmission graph Gt has an edge uv if and only if node v is in the transmission range of node u and the weight of uv is typically defined as II,,vll + c for a constant 2 <_ t ~ < 5 and c> O. The minimum power topology Gm is the smallest subgraph of Gt that contains the shortest paths between all pairs of nodes, i.e., the union of all shortest paths. In this paper, we described a distributed positionbased networking protocol to construct an enclosure graph G~, which is an approximation of Gin. The time complexity of each node u is O(min(dG ~ (u)dG ~ (u), dG ~ (u) log dG ~ (u))), where dc(u) is the degree of node u in a graph G. The space required at each node to compute the minimum power topology is O(dG ~ (u)). This improves the previous result that computes Gm in O(dG, (u) a) time using O(dGt(U) 2) spaces. We also show that the average degree dG,(u) is usually a constant, which is at most 6. Our result is first developed for stationary network and then extended to mobile networks. I.
Topology Control and Routing in Ad hoc Networks: A Survey
 SIGACT News
, 2002
"... this article, we review some of the characteristic features of ad hoc networks, formulate problems and survey research work done in the area. We focus on two basic problem domains: topology control, the problem of computing and maintaining a connected topology among the network nodes, and routing. T ..."
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Cited by 164 (0 self)
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this article, we review some of the characteristic features of ad hoc networks, formulate problems and survey research work done in the area. We focus on two basic problem domains: topology control, the problem of computing and maintaining a connected topology among the network nodes, and routing. This article is not intended to be a comprehensive survey on ad hoc networking. The choice of the problems discussed in this article are somewhat biased by the research interests of the author
Asynchronous Wakeup for Ad Hoc Networks
 Proc 4th ACM International Symposium on Mobile Ad Hoc Networking & Computing (MobiHoc 2003
, 2003
"... All intext references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately. ..."
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Cited by 146 (3 self)
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All intext references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
Localized minimumenergy broadcasting in AdHoc Networks
, 2003
"... In the minimum energy broadcasting problem, each node can adjust its transmission power in order to minimize total energy consumption but still enable a message originated from a source node to reach all the other nodes in an adhoc wireless network. In all existing solutions each node requires glob ..."
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Cited by 123 (6 self)
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In the minimum energy broadcasting problem, each node can adjust its transmission power in order to minimize total energy consumption but still enable a message originated from a source node to reach all the other nodes in an adhoc wireless network. In all existing solutions each node requires global network information (including distances between any two neighboring nodes in the network) in order to decide its own transmission radius. In this paper, we describe a new localized protocol where each node requires only the knowledge of its distance to all neighboring nodes and distances between its neighboring nodes (or, alternatively, geographic position of itself and its neighboring nodes). In addition to using only local information, our protocol is shown experimentally to be comparable to the best known globalized BIP solution. Our solutions are based on the use of relative neighborhood graph which preserves connectivity and is defined in localized manner.
Power Optimization in FaultTolerant Topology Control Algorithms for Wireless Multihop Networks
 in Proceedings of the 9th Annual International Conference on Mobile Computing and Networking. 2003
, 2003
"... In ad hoc wireless networks, it is crucial to minimize power consumption while maintaining key network properties. This work studies power assignments of wireless devices that minimize power while maintaining kfault tolerance. Specifically, we require all links established by this power setting be ..."
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Cited by 84 (6 self)
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In ad hoc wireless networks, it is crucial to minimize power consumption while maintaining key network properties. This work studies power assignments of wireless devices that minimize power while maintaining kfault tolerance. Specifically, we require all links established by this power setting be symmetric and form a kvertex connected subgraph of the network graph. This problem is known to be NPhard. We show current heuristic approaches can use arbitrarily more power than the optimal solution. Hence, we seek approximation algorithms for this problem. We present three approximation algorithms. The first algorithm gives an O(kα)approximation where α is the best approximation factor for the related problem in wired networks (the best α so far is O(log k).) With a more careful analysis, we show our second (slightly more complicated) algorithm is an O(k)approximation. Our third algorithm assumes that the edge lengths of the network graph form a metric. In this case, we present simple and practical distributed algorithms for the cases of 2 and 3connectivity with constant approximation factors. We generalize this algorithm to obtain an O(k 2c+2)approximation for general kconnectivity (2 ≤ c ≤ 4 is the power attenuation exponent). Finally, we show that these approximation algorithms compare favorably with existing heuristics. We note that all algorithms presented in this paper can be used to minimize power while maintaining kedge connectivity with guaranteed approximation factors.
Connected KCoverage Problem in Sensor Networks
 In Proceedings of the International Conference on Computer Communications and Networks (IC3N
, 2004
"... one approach to conserve energy is to keep only a small subset of sensors active at any instant. In this article, we consider the problem of selecting a minimum size connectedcover, which is defined as a set of ¡ sensors such that each point in the sensor network is “covered” by at least ..."
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Cited by 83 (5 self)
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one approach to conserve energy is to keep only a small subset of sensors active at any instant. In this article, we consider the problem of selecting a minimum size connectedcover, which is defined as a set of ¡ sensors such that each point in the sensor network is “covered” by at least
Sparse Power Efficient Topology for Wireless Networks
, 2002
"... We consider how to construct power efficient wireless ad hoc networks. We propose two different methods combining several wellknown proximity graphs including Gabriel graph and Yao graph, which can be constructed locally and efficiently. Firstly, we combine the Gabriel structure and the Yao struct ..."
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Cited by 63 (20 self)
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We consider how to construct power efficient wireless ad hoc networks. We propose two different methods combining several wellknown proximity graphs including Gabriel graph and Yao graph, which can be constructed locally and efficiently. Firstly, we combine the Gabriel structure and the Yao structure. The constructed topology has at most O(n) edges and each node has a bounded outdegree. Secondly, we use the Yao structure and then using the reverse of the Yao structure. The constructed topology is guaranteed to be connected if the original unit disk graph is connected. Every node has a bounded degree. The experimental results show that it has a bounded unicasting and broadcasting power stretch factor in practice.
SYMMETRIC CONNECTIVITY WITH MINIMUM POWER CONSUMPTION IN RADIO NETWORKS
"... We study the problem of assigning transmission ranges to the nodes of a multihop packet radio network (also known as static adhoc wireless network) so as to minimize the total power consumed under the constraint that enough power is provided to the nodes to ensure that the network is connected. Pr ..."
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Cited by 51 (6 self)
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We study the problem of assigning transmission ranges to the nodes of a multihop packet radio network (also known as static adhoc wireless network) so as to minimize the total power consumed under the constraint that enough power is provided to the nodes to ensure that the network is connected. Precisely, we require that the bidirectional links established by the transmission range of every node form a connected graph. We call this problem Symmetric MinPower Connectivity. Implicit results in previous papers are the NPHardness of Symmetric MinPower Connectivity, and a very simple 2approximation algorithm. Using similarity with the Steiner Tree problem, we improve the approximation ratio to 1 + (ln 3)=2 + ffl, and present a practical algorithm with approximation ratio at most 15=8.
Energyaware wireless networking with directional antennas: the case of sessionbased broadcasting and multicasting
 IEEE Trans. Mobile Computing
"... Abstract—We consider ad hoc wireless networks that use directional antennas and have limited energy resources. To explore quantitatively the advantage offered by the use of directional antennas over the case of omnidirectional antennas, we consider the case of connectionoriented multicast traffic. ..."
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Cited by 47 (2 self)
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Abstract—We consider ad hoc wireless networks that use directional antennas and have limited energy resources. To explore quantitatively the advantage offered by the use of directional antennas over the case of omnidirectional antennas, we consider the case of connectionoriented multicast traffic. Building upon our prior work on multicasting algorithms, we introduce two protocols that exploit the use of directional antennas and evaluate their performance. We observe significant improvement with respect to the omnidirectional case, in terms of both energy efficiency and network lifetime. Additionally, we show that further substantial increase in the network’s lifetime can be achieved by incorporating a simple measure of a node’s residual energy into the node’s cost function. Index Terms—Broadcast, multicast, energy efficient, directional antenna, ad hoc network. æ 1