@article{chattopadhyay_dai_eun_2021, title={Controlling Metastable Infection Patterns in Multilayer Networks via Interlink Design}, volume={8}, ISSN={["2327-4697"]}, DOI={10.1109/TNSE.2021.3108075}, abstractNote={Recent research on epidemic spreading in networks has uncovered the phenomena of metastable infection patterns, where epidemics can be sustained in localized regions of activity, in contrast to the classical dichotomy between a quick extinction of infections and a network-wide global infection. Our objective in this work is to leverage this localized infection state to achieve controlled spreading in multilayer networks via intelligent design of the interlink structure between the network layers. Following the approach in recent works, the dynamic contact process is approximated by studying the dynamics in local regions around the hubs of the network. This allows us to approximately track the contact process in the near-threshold regime and estimate the mean metastable infection size over the lifetime of the infection. Furthermore, interlinking strategies are devised that can achieve a desired infection size under certain conditions. Theoretically optimal interlink structures can be derived under special cases, whereas greedy strategies are proposed for the general case. We compare the interlinking strategies developed in this work to some popular heuristics and demonstrate their superiority by extensive simulation experiments on both synthetic and real-world networks.}, number={4}, journal={IEEE TRANSACTIONS ON NETWORK SCIENCE AND ENGINEERING}, author={Chattopadhyay, Srinjoy and Dai, Huaiyu and Eun, Do Young}, year={2021}, month={Oct}, pages={3242–3256} } @article{chattopadhyay_dai_eun_2020, title={Maximization of Robustness of Interdependent Networks Under Budget Constraints}, volume={7}, ISSN={["2327-4697"]}, DOI={10.1109/TNSE.2019.2935068}, abstractNote={We consider the problem of interlink optimization in multilayer interdependent networks under cost constraints, with the objective of maximizing the robustness of the network against component (node) failures. Diverting from the popular approaches of branching process based analysis of the failure cascades or using a supra-adjacency matrix representation of the multilayer network and employing classical metrics, in this work, we present a surrogate metric based framework for constructing interlinks to maximize the network robustness. In particular, we focus on three representative mechanisms of failure propagation, namely, connected component based cascading failure, load distribution in interdependent networks, and connectivity in demand-supply networks, and propose metrics to track the network robustness for each of these mechanisms. Owing to their mathematical tractability, these metrics allow us to optimize the interlink structure to enhance robustness. Furthermore, we are able to introduce the cost of construction into the interlink design problem, a practical feature largely ignored in relevant literature. We simulate the failure cascades on real world networks to compare the performance of our interlinking strategies with the state of the art heuristics and demonstrate their effectiveness.}, number={3}, journal={IEEE TRANSACTIONS ON NETWORK SCIENCE AND ENGINEERING}, author={Chattopadhyay, Srinjoy and Dai, Huaiyu and Eun, Do Young}, year={2020}, pages={1441–1452} } @article{chattopadhyay_dai_eun_hosseinalipour_2017, title={Designing Optimal Interlink Patterns to Maximize Robustness of Interdependent Networks Against Cascading Failures}, volume={65}, ISSN={["1558-0857"]}, DOI={10.1109/tcomm.2017.2709302}, abstractNote={In this paper, we consider the optimal design of interlinks for an interdependent system of networks. In contrast to existing literature, we explicitly exploit the information of intra-layer node degrees to design interdependent structures such that their robustness against cascading failures, triggered by randomized attacks, is maximized. Utilizing percolation theory-based system equations relating the robustness of the network to its degree sequence, we characterize the optimal design for the one-to-one structure, with complete interdependence and partial interdependence, under randomized attack. We also extend our study to the one-to-many interdependence structure and the targeted attack model. The theoretically derived optimal interdependence structures have been verified using simulations on scale-free networks.}, number={9}, journal={IEEE TRANSACTIONS ON COMMUNICATIONS}, author={Chattopadhyay, Srinjoy and Dai, Huaiyu and Eun, Do Young and Hosseinalipour, Seyyedali}, year={2017}, month={Sep}, pages={3847–3862} } @inproceedings{chattopadhyay_dai_2017, title={Designing optimal interlink structures for interdependent networks under budget constraints}, DOI={10.1109/icc.2017.7997212}, abstractNote={In this work, we focus on the problem of obtaining the optimal interlink structures, which maximizes the robustness of networks against random node failures, in a cost constrained setting. Using percolation theory based system equations, we have formulated our objective as a constrained optimization problem and designed algorithms serving two key purposes: i) obtaining the budget limits, Bl and Bu, defined as the minimum budget guaranteeing the existence of a feasible and optimal interlink structure, respectively; and ii) obtaining interlink structures for intermediate budgets. Through these algorithms and associated simulation results, we demonstrate the importance of cost in network design. Furthermore, the designed algorithms have close to optimal performance while being much cheaper than cost agnostic network designs.}, booktitle={2017 ieee international conference on communications (icc)}, author={Chattopadhyay, S. and Dai, H. Y.}, year={2017} } @inproceedings{chattopadhyay_dai_2016, title={Estimation of robustness of interdependent networks against failure of nodes}, DOI={10.1109/glocom.2016.7841822}, abstractNote={Abstract-We consider a partially interdependent network and develop mathematical equations relating the fractional size of the connected component of the network, surviving the cascading failure, to the intra-layer degree distribution of the nodes. We show that these system equations can be mathematically analyzed and closed form expressions for the metrics of robustness can be obtained for the Erdos-Renyi (ER) model of random graph generation. We have described the application of our analysis technique to networks with general degree distributions. In our analysis, we consider the two extremes of the attack model: randomized attack, where nodes are attacked at random without any knowledge of intra-layer degrees and perfect targeted attack, where nodes are attacked based on the strict descending order of their intra-layer degrees. Our results can enable researchers to gain a better understanding of the robustness of interdependent networks.}, booktitle={2016 ieee global communications conference (globecom)}, author={Chattopadhyay, S. and Dai, H. Y.}, year={2016} } @article{chattopadhyay_dai_2015, title={Towards Optimal Link Patterns for Robustness of Interdependent Networks against Cascading Failures}, ISSN={["2576-6813"]}, DOI={10.1109/glocom.2015.7417333}, abstractNote={In this work we consider the optimal design of interconnection links for an interdependent system of networks. In contrast to existing literature, we explicitly exploit the information of intra- layer node degrees to design more robust interdependency structure against cascading failures triggered by random attacks. Built on solid mathematical models, we characterize the optimal design for the one-to-one structure, with complete interdependence and partial interdependence. We also extend the study to the one-to-many structure and targeted attack model. Simulation results are provided to corroborate the theoretical results.}, journal={2015 IEEE GLOBAL COMMUNICATIONS CONFERENCE (GLOBECOM)}, author={Chattopadhyay, Srinjoy and Dai, Huaiyu}, year={2015} }