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June 26, 2021

Prof. Dr. Georgios Smaragdakis


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Prof. Dr. Georgios Smaragdakis
030 314-75169

COVID-19: A stress test for the internet


On 11 March 2020, the day the WHO declared the coronavirus a global pandemic, the impact of SARS-CoV-2 also spread to the World Wide Web. Following this announcement, governments around the world began enacting stay-at-home orders and other regulations for working from home and homeschooling. Within a single week, Internet traffic volume increased by 25 percent – an increase which under normal circumstances is usually observed over the course of a year. Taking account of increased use during the second lockdown in fall 2020, the overall use of Internet services in 2020 increased between 35 and 50 percent, depending on the network. An international, interdisciplinary group of researchers led by Professor Dr. Georgios Smaragdakis, professor of Internet measurement and analysis at TU Berlin and Fellow of the Berlin Institute for the Foundations of Learning and Data (BIFOLD), has published these figures and other findings in a paper in Communications of the Association for Computing Machinery (ACM). The leading professional association recently named the paper a research highlight.

From essentially one day to the next, almost nothing was possible without a stable Internet connection. Since March of last year, team meetings, school lessons, and even private celebrations have primarily been held via digital screens. Those without a broadband connection or sufficient electronic devices have missed out. Despite the worldwide restrictions necessitated by COVID-19, life continued with the Internet playing an important role for companies, the education sector, entertainment, retail, and social interactions. “In the spring of 2020, no one could say with certainty whether the Internet would be able to withstand this rush demand,” explains Georgios Smaragdakis. “No one had previously expected a sudden surge in Internet traffic of such proportions.” In their project, financed in part by BIFOLD, the researchers investigated Internet data streams from different Internet providers across Europe. “Together they provide us with a good understanding of the impacts that the COVID-19 waves and lockdown measures had on Internet traffic,” continues Georgios Smaragdakis.

Within a year of the implementation of the first lockdown measures, the aggregate volume of Internet data traffic increased by approximately 40 percent, significantly more than the expected annual growth. At the same time, mobile data traffic first slightly decreased and then only grew moderately, as people were out and about less, thus using less mobile data. “Our calculations show that the use of services such as video conferencing and VPNs increased by up to 300 percent. Gaming applications also significantly increased. After moderate growth during the spring lockdown, use increased by about 300 percent during the fall lockdown. And while these applications were primarily used in the evening or on the weekend pre-pandemic, gaming usage increases were evenly distributed across each day of the week during the second lockdown, mainly in the mornings,” remarks Georgios Smaragdakis.

Overall traffic patterns in Internet usage have clearly changed: While peak times before the pandemic were on the weekend and in the evening, the sudden growth in Internet usage primarily occurred on weekdays during working hours. This asynchronous growth is precisely one reason why researchers believe the Internet was able to handle the increased traffic relatively well. Smaragdakis believes the good structure and overprovisioning of the network operators also helped.

“In terms of digitalization, the last months have been a tremendous success,” says Smaragdakis. “In just a matter of weeks, German universities and government authorities adopted developments that they had previously failed to implement in years. These days, a broadband connection is not just something that is nice to have, but rather an essential requirement to be able to work. This level of digitalization is the new normal. It will not be possible to return to previous practices.”

The researchers’ study also shows that overprovisioning, proactive network management, and automatization were key to providing resistant networks which could cope with the drastic and unexpected fluctuations in demand like those experienced during the COVID-19 pandemic. “Many, but not all, network providers succeeded in doing this. With the pandemic set to continue for some time, it is important that we continue to examine data traffic to understand how usage changes during these unprecedented times,” he concludes.

Anja Feldmann, Oliver Gasser, Franziska Lichtblau, Enric Pujol, Ingmar Poese, Christoph Dietzel, Daniel Wagner, Matthias Wichtlhuber, Juan Tapiador, Narseo Vallina-Rodriguez, Oliver Hohlfeld, Georgios Smaragdakis
In 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.
Communications of the ACM, July 2021, Vol. 64 No. 7, Pages 101-108