01617nas a2200253   4500008004100000022001400041245006100055210006000116300001000176490000600186520088300192653001801075653001501093653002401108653001501132100002001147700003001167700002301197700002601220700002201246700002701268700002901295856003901324       2020                        eng d  a2167-835900aEcosystem antifragility: beyond integrity and resilience0 aEcosystem antifragility beyond integrity and resilience  ae85330 v83 aWe review the concept of ecosystem resilience in its relation to ecosystem integrity from an information theory approach. We summarize the literature on the subject identifying three main narratives: ecosystem properties that enable them to be more resilient; ecosystem response to perturbations; and complexity. We also include original ideas with theoretical and quantitative developments with application examples. The main contribution is a new way to rethink resilience, that is mathematically formal and easy to evaluate heuristically in real-world applications: ecosystem antifragility. An ecosystem is antifragile if it benefits from environmental variability. Antifragility therefore goes beyond robustness or resilience because while resilient/robust systems are merely perturbation-resistant, antifragile structures not only withstand stress but also benefit from it.10aAntifragility10aComplexity10aEcosystem integrity10aResilience1 aEquihua, Miguel1 aAldama, Mariana, Espinosa1 aGershenson, Carlos1 aLópez-Corona, Oliver1 aMunguía, Mariana1 aPérez-Maqueo, Octavio1 aRamírez-Carrillo, Elvia  uhttps://doi.org/10.7717/peerj.853301685nas a2200181   4500008004100000020001400041245006200055210006000117300000900177520113900186653003301325653001501358653001401373653002301387100002201410700002301432856004801455       2015                        eng d  a1936-644200aMeasuring the complexity of adaptive peer-to-peer systems0 aMeasuring the complexity of adaptive peertopeer systems  a1-163 aTo improve the efficiency of peer-to-peer (P2P) systems while adapting to changing environmental conditions, static peer-to-peer protocols can be replaced by adaptive plans. The resulting systems are inherently complex, which makes their development and characterization a challenge for traditional methods. Here we propose the design and analysis of adaptive P2P systems using measures of complexity, emergence, self-organization, and homeostasis based on information theory. These measures allow the evaluation of adaptive P2P systems and thus can be used to guide their design. We evaluate the proposal with a P2P computing system provided with adaptation mechanisms. We show the evolution of the system with static and also changing workload, using different fitness functions. When the adaptive plan forces the system to converge to a predefined performance level, the nodes may result in highly unstable configurations, which correspond to a high variance in time of the measured complexity. Conversely, if the adaptive plan is less ``aggressive'', the system may be more stable, but the optimal performance may not be achieved.10aAdaptive peer-to-peer system10aComplexity10aEvolution10aInformation theory1 aAmoretti, Michele1 aGershenson, Carlos  uhttp://dx.doi.org/10.1007/s12083-015-0385-4