Feldmann, AnjaGasser, OliverLichtblau, FranziskaPujol, EnricPoese, IngmarDietzel, ChristophWagner, DanielWichtlhuber, MatthiasEstévez Tapiador, Juan ManuelVallina-Rodriguez, NarseoHohlfeld, OliverSmaragdakis, Georgios2024-07-232024-07-232021-06-21Anja Feldmann, Oliver Gasser, Franziska Lichtblau, Enric Pujol, Ingmar Poese, Christoph Dietzel, Daniel Wagner, Matthias Wichtlhuber, Juan Tapiador, Narseo Vallina-Rodriguez, Oliver Hohlfeld, and Georgios Smaragdakis. 2021. A year in lockdown: how the waves of COVID-19 impact internet traffic. Commun. ACM 64, 7 (July 2021), 101–1080001-0782https://hdl.handle.net/10016/44201In March 2020, the World Health Organization declared the Corona Virus 2019 (COVID-19) outbreak a global pandemic. As a result, billions of people were either encouraged or forced by their governments to stay home to reduce the spread of the virus. This caused many to turn to the Internet for work, education, social interaction, and entertainment. With the Internet demand rising at an unprecedented rate, the question of whether the Internet could sustain this additional load emerged. To answer this question, this paper will review the impact of the first year of the COVID-19 pandemic on Internet traffic in order to analyze its performance. In order to keep our study broad, we collect and analyze Internet traffic data from multiple locations at the core and edge of the Internet. From this, we characterize how traffic and application demands change, to describe the "new normal" and explain how the Internet reacted during these unprecedented times.en© 2021 Owner/Author.Creative Commons Attribution-NonCommercial International 4.0 License.NetworksNetwork perforance evaluationNetwork measurementresearch articleInformáticahttp://dx.doi.org/10.1145/3465212open access1017108COMMUNICATIONS OF THE ACM64AR/0000034963