What is DNS? A computer engineer explains this foundational piece of the web – and why it’s the internet’s Achilles’ heel
- Written by Doug Jacobson, University Professor of Electrical and Computer Engineering, Iowa State University
Amazon Web Services, hosted in data centers like this one in Virginia, supports thousands of websites, apps and online services – but not during its recent DNS outage.Nathan Howard/Getty ImagesWhen millions of people suddenly couldn’t load familiar websites and apps during the Amazon Web Services, or AWS, outage on Oct. 20, 2025, the...










