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39
On Reducing Broadcast Redundancy in Ad Hoc Wireless Networks
, 2003
"... Unlike in a wired network, a packet transmitted by a node in an ad hoc wireless network can reach all neighbors. Therefore, the total number of transmissions (forward nodes) is generally used as the cost criterion for broadcasting. The problem of finding the minimum number of forward nodes is NPcomp ..."
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Cited by 112 (23 self)
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Unlike in a wired network, a packet transmitted by a node in an ad hoc wireless network can reach all neighbors. Therefore, the total number of transmissions (forward nodes) is generally used as the cost criterion for broadcasting. The problem of finding the minimum number of forward nodes is NPcomplete. Among various approximation approaches, dominant pruning [7] utilizes 2hop neighborhood information to reduce redundant transmissions. In this paper, we analyze some deficiencies of the dominant pruning algorithm and propose two better approximation algorithms: total dominant pruning and partial dominant pruning. Both algorithms utilize 2hop neighborhood information more effectively to reduce redundant transmissions. Simulation results of applying these two algorithms show performance improvements compared with the original dominant pruning. In addition, two termination criteria are discussed and compared through simulation.
Broadcast capacity in multihop wireless networks
 In MobiCom
, 2006
"... Abstract — In this paper we study the broadcast capacity of multihop wireless networks which we define as the maximum rate at which broadcast packets can be generated in the network such that all nodes receive the packets successfully within a given time. To asses the impact of topology and interfer ..."
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Cited by 74 (5 self)
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Abstract — In this paper we study the broadcast capacity of multihop wireless networks which we define as the maximum rate at which broadcast packets can be generated in the network such that all nodes receive the packets successfully within a given time. To asses the impact of topology and interference on the broadcast capacity we employ the Physical Model and Generalized Physical Model for the channel. Prior work was limited either by density constraints or by using the less realistic but manageable Protocol model [1], [2]. Under the Physical Model, we find that the broadcast capacity is within a constant factor of the channel capacity for a wide class of network topologies. Under the Generalized Physical Model, on the other hand, the network configuration is divided into three regimes depending on how the power is tuned in relation to network density and size and in which the broadcast capacity is asymptotically either zero, constant or unbounded. As we show, the broadcast capacity is limited by distant nodes in the first regime and by interference in the second regime. In the second regime, which covers a wide class of networks, the broadcast capacity is within a constant factor of the bandwidth. I.
LowInterference Topology Control for Wireless Ad Hoc Networks
 ACM Wireless Networks
, 2005
"... supported by NSF CCR0311174. Abstract — Topology control has been well studied in wireless ad hoc networks. However, only a few topology control methods take into account the low interference as a goal of the methods. Some researchers tried to reduce the interference by lowering node energy consump ..."
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Cited by 56 (0 self)
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supported by NSF CCR0311174. Abstract — Topology control has been well studied in wireless ad hoc networks. However, only a few topology control methods take into account the low interference as a goal of the methods. Some researchers tried to reduce the interference by lowering node energy consumption (i.e. by reducing the transmission power) or by devising low degree topology controls, but none of those protocols can guarantee low interference. Recently, Burkhart et al. [?] proposed several methods to construct topologies whose maximum link interference is minimized while the topology is connected or is a spanner for Euclidean length. In this paper we give algorithms to construct a network topology for wireless ad hoc network such that the maximum (or average) link (or node) interference of the topology is either minimized or approximately minimized. Index Terms — Topology control, interference, wireless ad hoc networks.
Forwardnodesetbased broadcast in clustered mobile ad hoc networks
 Wireless Communication and Mobile Computing
, 2003
"... A taxonomy of broadcast protocols in mobile ad hoc networks (MANETs) is given where protocols are classified into four groups: global, quasiglobal, quasilocal, and local. The taxonomy also divides protocols based on the nature of algorithms: probabilistic and deterministic. The locality of mainten ..."
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Cited by 48 (14 self)
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A taxonomy of broadcast protocols in mobile ad hoc networks (MANETs) is given where protocols are classified into four groups: global, quasiglobal, quasilocal, and local. The taxonomy also divides protocols based on the nature of algorithms: probabilistic and deterministic. The locality of maintenance also plays an important role in evaluating the protocol. An important objective in designing a broadcast protocol is to reduce broadcast redundancy to save scarce resources such as energy and bandwidth and to avoid the broadcast storm problem. This objective should be achieved without introducing excessive overhead and time delay, measured by the sequential rounds of information exchanges. This is done by choosing a small forward node set that forms a connected dominating set (CDS) to carry out a broadcast process. In this paper, a clustered network model is proposed in which each node is a clusterhead in the clustered architecture. Clusterheads are connected by carefully selecting nonclusterhead nodes locally at each clusterhead to connect clusterheads within 2.5 hops, a novel notion proposed in this paper. Information of neighbor clusterheads are piggybacked with the broadcast packet to further reduce each forward node set. It is shown that this approach is quasilocal with locality of maintenance. In addition, this approach has a constant approximation ratio to the minimum connected dominating set (MCDS) and generates a small forward node set in the average case. Comparisons are also done through simulation with representative protocols from each of the four groups of protocols based on the proposed taxonomy.
Computing 2Hop Neighborhoods in Ad Hoc Wireless Networks
 In ADHOCNOW’03
, 2003
"... We present efficient distributed algorithms for computing 2hop neighborhoods in Ad Hoc Wireless Networks. The knowledge of the 2hop neighborhood is assumed in many protocols and algorithms for routing, clustering, and distributed channel assignment, but no efficient distributed algorithms for comp ..."
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Cited by 36 (0 self)
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We present efficient distributed algorithms for computing 2hop neighborhoods in Ad Hoc Wireless Networks. The knowledge of the 2hop neighborhood is assumed in many protocols and algorithms for routing, clustering, and distributed channel assignment, but no efficient distributed algorithms for computing the 2hop neighborhoods were previously published. The problem is nontrivial,...
Algorithmic, Geometric and Graphs Issues in Wireless Networks
 Wireless Communications and Mobile Computing
, 2002
"... We present an overview of the recent progress of applying computational geometry techniques to solve some questions, such as topology construction and broadcasting, in wireless ad hoc networks. Treating each wireless device as a node in a two dimensional plane, we model the wireless networks by unit ..."
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Cited by 24 (2 self)
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We present an overview of the recent progress of applying computational geometry techniques to solve some questions, such as topology construction and broadcasting, in wireless ad hoc networks. Treating each wireless device as a node in a two dimensional plane, we model the wireless networks by unit disk graphs in which two nodes are connected if their Euclidean distance is no more than one. We rst summarize the current status of constructing sparse spanners for unit disk graphs with various combinations of the following properties: bounded stretch factor, bounded node degree, planar, and bounded total edges weight (compared with the minimum spanning tree). Instead of constructing subgraphs by removing links, we then review the algorithms for constructing a sparse backbone (connected dominating set), i.e., subgraph from the subset of nodes. We then review some ecient methods for broadcasting and multicasting with theoretic guaranteed performance.
Constantfactor approximation for minimumweight (connected) dominating sets in unit disk graphs
 In: Proc. of the 9 th Int. Workshop on Approximation Algorithms for Combinatorial Optimization Problems (APPROX). (2006
, 2006
"... For a given graph with weighted vertices, the goal of the minimumweight dominating set problem is to compute a vertex subset of smallest weight such that each vertex of the graph is contained in the subset or has a neighbor in the subset. A unit disk graph is a graph in which each vertex correspond ..."
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Cited by 24 (1 self)
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For a given graph with weighted vertices, the goal of the minimumweight dominating set problem is to compute a vertex subset of smallest weight such that each vertex of the graph is contained in the subset or has a neighbor in the subset. A unit disk graph is a graph in which each vertex corresponds to a unit disk in the plane and two vertices are adjacent if and only if their disks have a nonempty intersection. We present the first constantfactor approximation algorithm for the minimumweight dominating set problem in unit disk graphs, a problem motivated by applications in wireless adhoc networks. The algorithm is obtained in two steps: First, the problem is reduced to the problem of covering a set of points located in a small square using a minimumweight set of unit disks. Then, a constantfactor approximation algorithm for the latter problem is obtained using enumeration and dynamic programming techniques exploiting the geometry of unit disks. Furthermore, we show how to obtain a constantfactor approximation algorithm for the minimumweight connected dominating set problem in unit disk graphs. Our techniques also yield a constantfactor approximation algorithm for the weighted disk cover problem (covering a set of points in the plane with unit disks of minimum total weight) and a 3approximation algorithm for the weighted forwarding set problem (covering a set of points in the plane with weighted unit disks whose centers are all contained in a given unit disk). 1
Extended multipoint relays to determine connected dominating sets in MANETs
 IEEE Transactions on Computers
, 2006
"... Abstract — Multipoint relays (MPR) [1] provides a localized and optimized way of broadcasting messages in a mobile ad hoc network (MANET). Using 2hop neighborhood information, each node determines a small set of forward neighbors to relay messages. Selected forward nodes form a connected dominating ..."
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Cited by 24 (0 self)
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Abstract — Multipoint relays (MPR) [1] provides a localized and optimized way of broadcasting messages in a mobile ad hoc network (MANET). Using 2hop neighborhood information, each node determines a small set of forward neighbors to relay messages. Selected forward nodes form a connected dominating set (CDS) to ensure full coverage. Adjih, Jacquet, and Viennot [2] proposed a novel localized algorithm to construct a small CDS based on the original MPR. In this paper, we provide several extensions to generate a smaller CDS using 3hop neighborhood information to cover each node’s 2hop neighbor set. In addition, we extend the notion of coverage in the original MPR. We show that the extended MPR has a constant local approximation ratio compared with a logarithmic local ratio in the original MPR. The effectiveness of our approach is confirmed through a simulation study.
New metrics for dominating set based energy efficient activity scheduling in ad hoc networks
 In Proc. of the International Workshop on Wireless Local Networks (WLN
, 2003
"... In a multihop wireless network, each node is able to send a message to all of its neighbors that are located within its transmission radius. In a flooding task, a source sends the same message to all the network. Routing problem deals with finding a route between a source and a destination. In the ..."
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Cited by 19 (14 self)
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In a multihop wireless network, each node is able to send a message to all of its neighbors that are located within its transmission radius. In a flooding task, a source sends the same message to all the network. Routing problem deals with finding a route between a source and a destination. In the activityscheduling problem, each node decides between active or passive state. We present a scheme whose goal is to prolong network life while preserving connectivity. Each node is either active or has an active neighbor node. Routing and broadcasting are restricted to active nodes that create such dominating set. Activity status is periodically updated during a short transition period. The main contribution of this article is to propose new metrics for previously studied sourceindependent localized dominating sets, based on combinations of node degrees and remaining energy levels, for deciding activity status. 1.