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Wireless ad hoc networks are often considered an alternative for providing communication means to support urgent and temporary tasks. In such settings, network connectivity is a primary condition to allow nodes to exchange information. In this work we explore the use of cooperative communication (CC) techniques for improving network connectivity. The proposed solution, named Connectivity Autorecovering with Cooperative Communication (CARCC), monitors potential network disruption points and proactively creates cooperative links (CC-links). These links are used to regain network connectivity when necessary. CARCC allows the selection of suitable CC-links in (Δ( ) × Λ) time, whereas a centralized approach takes ( 2 × Λ) time, where Δ( ) is the degree of the underline network graph ( , ) and Λ is the computational cost of selecting helper nodes. Although CARCC relies on localized information, it is able to provide comparable results of other noteworthy alternatives that require global topological information. The CC-links provided by CARCC reestablished network connectivity in over 91% in the evaluated settings.A sizable number of solutions have been proposed in the literature aiming at ensuring network connectivity. Li and Hou [1] addressed the problem of adding as few nodes as possible so that the resulting network topology is connected. They proved that this task is NP-complete and proposed a Delaunay triangulation-based heuristic to tackle it. Goyal and Caffery [2] proposed the use of limited, coordinated mobility, to recover from link and node failures. In case of network disruption, nodes would move in a coordinated way to reestablish connectivity. Articulation points (a.k.a. cut-vertices) may appear during the network operation as a result of battery depletion, node movement, or event due to link failure. As the failure of an articulation point renders the network disconnected, Yong and Hu [3] presented a mathematical model to predict the formation of articulations based on network characteristics and node activity. Afonseca et al. [4] proposed the use of packet aggregation techniques for reducing energy consumption of articulation nodes that could render the network disconnected. Khelifa et al. [5] proposed the use of redundant nodes that could be moved

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Wireless Sensor Networks (WSN) are characterized by their capacity of monitoring the environment, gathering and sharing information. Nodes in a WSN usually cooperate in the task of forwarding the sensed data to a sink node for later retrieval and analysis. The success of this task depends on the availability of efficient routes that meet the application requirements. As topology may change overtime, alternatives to improve and maintain network connectivity are highly desired. In this context, Cooperative Communication (CC) emerged as an alternative to improve network connectivity. Despite its benefits, CC-links are known to have higher energy demands as compared to traditional, direct, links. In particular, CC-links require the source node to expend more power than others nodes, shortening their life span. The main contribution of this paper is to propose a new Cooperative Communication model, capable of increasing the energy balance of the CClinks while improving network connectivity. Simulation results show that, compared to other CC schemes, the source node of a Cooperative Communication reduces the amount of expended energy by 68% in the evaluated settings.