When most people think about the internet, they likely picture websites and apps. What they rarely see are the invisible services that make those experiences possible: systems that translate names into numbers, verify who you are, deliver messages and block malicious traffic.
For example, DNS, the Domain Name System, has quietly become a single point of failure. DNS is the internet’s phone book. When it fails, large parts of the internet effectively disappear, even if servers are still running.
DNS is not alone. Over the past decade, four core internet services – DNS, authentication, email and security infrastructure – have consolidated into a small number of global platforms. As a cybersecurity researcher, I see that this concentration has fundamentally changed how outages unfold. What would once have been a local failure is now often a systemic event, affecting thousands of organizations simultaneously.
The internet was designed to assume failure. Mail servers, DNS resolvers, authentication systems and security monitors were meant to be distributed and locally controlled. Today, for reasons that make economic sense, many companies and organizations outsource all four to the same handful of providers. One cloud service monitoring organization referred to 2025 as the year of the global cloud outage.
An Amazon Web Services outage on Oct. 20, 2025, took down many popular websites and apps for several hours.
DNS, authentication, email and security
Outages are no longer rare exceptions, but a predictable byproduct of efficiency at a global scale. That pattern becomes apparent when you look at a few major outages that have affected each of the four services.
DNS outages are a prime example of systemic risk. If DNS cannot resolve a name, a website may as well not exist. A growing share of global DNS resolution now depends on a small number of providers. That concentration means that a single configuration error, routing issue or attack can ripple across much of the web.
Authentication outages are less visible to the public but often more disruptive inside organizations.
For example, on Oct. 29, 2025, Microsoft Azure experienced a major outage that disrupted authentication and access for millions of users worldwide for over five hours. Another authentication provider, Okta, suffered an outage on Oct. 3.
Authentication has become a universal gatekeeper. When identity services fail, modern organizations don’t degrade gracefully; they come to a halt.
Despite decades of predictions about its decline, email remains a central component of how employers function. Password resets, invoices, legal notices, emergency notifications and incident response coordination all depend on it. When large cloud email providers experience outages, companies and organizations not only lose communication but also struggle to recover accounts and coordinate recovery efforts…
