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Wireless sensor networks (WSNs) are self-organizing systems where computing devices, so called motes (or nodes), set up–by themselves–a networking infrastructure without relying on external assistance. In this paper, we focus on medium access control (MAC) in WSNs. We present DecTDMA (Decentralized-TDMA)—a fully-decentralized MAC protocol for WSNs. Our decentralized solution does not assume access to external references, such as wireless access points (WAPs), and individual nodes in DecTDMA do not have special tasks, such as acting as elected coordinators. In this work, we aim to mitigate one of the key sources of internal interference: concurrent transmissions by neighboring motes, which cause radio interferences. The event of concurrent transmissions refers to the occurrence of multiple transmissions, such that the periods of these transmissions overlap. Concurrent transmissions have a great impact on the throughput in WSNs. For example, they can reduce the packet reception ratio (PRR)[26]. DecTDMA uses a self-stabilizing algorithm [19] for time division multiple access (TDMA) that significantly reduces the occurrence of concurrent transmissions. In addition, we show that DecTDMA deals well with other causes of WSN dynamics, such as mote or link failure and wireless links of intermediate quality, ie, links with a PRR between 10% and 90%. DecTDMA uses a link quality estimation (LQE) technique for estimating the PRR of both broadcasts and their respective acknowledgements. We use this elegant (lightweight) and softwarebased technique for masking short term link failures, ie, sporadic (receiver-side) packet …