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Multipoint relays (MPR) [18] provide a localized and optimized way of broadcasting messages in a mobile ad hoc network (MANET). Using partial 2-hop information, each node chooses a small set of forward neighbors to relay messages and this set covers the node's 2-hop neighbor set. These selected forward nodes form a connected dominating set (CDS) to ensure full coverage. Adjih et al. [1] later proposed a novel extension of MPR to construct a small CDS and it is source-independent. In this paper, we provide several extensions to generate a smaller COS using complete 2-hop information to cover each node's 2-hop neighbor set. We extend the notion of coverage in the original MPR. We prove that the extended MPR has a constant local approximation ratio compared with a logarithmic local ratio in the original MPR. In addition, we show that the extended MPR has a constant global probabilistic approximation ratio, while no such ratio exists in the original MPR and its existing extensions. The effectiveness of our approach is confirmed through a simulation study. [ABSTRACT FROM AUTHOR]

Sensor networks usually operate under very severe energy restrictions. Therefore, sensor communications should consume the minimum possible amount of energy. While broadcasting is a very energy-expensive protocol, it is also widely used as a building block for a variety of other network layer protocols. Therefore, reducing the energy consumption by optimizing broadcasting is a major improvement in sensor networking. In this paper, we propose an optimized Broadcast Protocol for Sensor networks (BPS). The major novelty of BPS is its adaptive-geometric approach that enables considerable reduction of retransmissions by maximizing each hop length. BPS adapts itself and gets the best out of existing radio conditions. In BPS, nodes do not need any neighborhood information, which leads to low communication and memory overhead. We analyze the worst-case scenario for BPS and show that the number of transmissions in such a scenario is a constant multiple of those required in the ideal case. Our simulation results show that BPS is very scalable with respect to network density. BPS is also resilient to transmission errors. [ABSTRACT FROM AUTHOR]

We propose a generic framework for distributed broadcasting in ad hoc wireless networks. The approach is based on selecting a small subset of nodes to form a forward node set to carry out a broadcast process. The status of each node, forward or nonforward, is determined either by the node itself or by other nodes. Node status can be determined at different snapshots of network state along time (called views) without causing problems in broadcast coverage. Therefore, the forward node set can be constructed and maintained through either a proactive process (i.e., "up-to-date") before the broadcast process or a reactive process (i.e., "on-the- fly") during the broadcast process. A sufficient condition, called coverage condition, is given for a node to take the nonforward status. Such a condition can be easily checked locally around the node. Several existing broadcast algorithms can be viewed as special cases of the generic framework with k-hop neighborhood information. A comprehensive comparison among existing algorithms is conducted. Simulation results show that new algorithms, which are more efficient than existing ones, can be derived from the generic framework. [ABSTRACT FROM AUTHOR]