Facebook, Instagram and Whatsapp were offline for more than six hours on Monday evening. In the meantime, the services are running again. But other problems of the company still exist: Today, Tuesday, the whistleblower Frances Haugen will testify in the U.S. Senate and repeat her serious accusations. At least Facebook was able to get the technical outage under control during the night, and it is now clear what was behind it. Answers to the most important questions:

Why are Facebook services down?

The blog entry posted by the company does not contain too many details: Facebook writes that an error was made in the configuration of the routers that control the data traffic between the data centers. The company Cloudflare, which operates part of the Internet's infrastructure, explains it in much more detail. Put simply, the three Facebook services have disappeared from the map of the World Wide Web.

When you type facebook.com into the browser or open the Instagram app, the so-called Border Gateway Protocol (BGP) forwards the request to the correct IP address. The protocol is the guide for the Domain Name System (DNS), a kind of phone book for the Internet. Without this orientation, the devices don't know where to find Facebook, Instagram and Whatsapp. Apparently, someone at Facebook accidentally deleted the entries in the BGP or linked them incorrectly; accordingly, three of the world's largest communication platforms became invisible. Even experts do not yet know how and why this happened.

Did user data leak out in the process?

Facebook says that there was no hacker attack behind the outage, but rather a mistake. There are no indications that attackers have captured any data. So far, there is no reason to doubt this explanation.

Why did the disruption last so long?

The problem affected not only users, but also Facebook employees. The internal Workplace communication platform, calendars and other services were down. Employees could no longer make calls or receive e-mails on their work cell phones. Some were locked out of office buildings and conference rooms because their access cards no longer worked. This probably also affected programmers who were supposed to fix the problem. Instagram CEO Adam Mosseri, for example, wrote on Twitter that it felt like a "snow day," the U.S. version of heat-free.

What was the impact of the outage?

Around three billion people were unable to communicate via the platforms of their choice for a while. For most users in Western countries, the damage was limited: Then the selfie will just have to wait a few hours. Urgent matters can also be resolved by phone. Companies have already been affected more severely; after all, Instagram in particular is an important marketing platform. Advertisers who place ads on Facebook are also likely to feel the effects.

This is harmless compared to the consequences in the so-called Global South. In some countries, Facebook services are synonymous with the Internet; in Brazil and India, for example, people pay with Whatsapp. For many refugees, Messenger is the only channel through which they keep in touch with family and friends. In Afghanistan, hundreds of thousands are still hiding from the Taliban and exchanging information with their relatives via Whatsapp.

Who has benefited from this?

Twitter knew only one topic on Monday evening: #facebookdown, #whatsappdown and "Great Reset" dominated the trending topics. The official account @Twitter welcomed "literally everyone", even the social media teams of Whatsapp and Instagram commented under the tweet - where else should they write? Jack Dorsey also had his fun: "Signal is WhatsUp," wrote the Twitter boss. The Whatsapp competitors would not have needed this advertising: Telegram climbed to first place in the app charts, Signal welcomed millions of new users.

Has there ever been a comparable outage?

The service Downdetector speaks of the largest outage in history. But that only refers to the number of reports. The more people are online, the more people complain when something doesn't work. In fact, there have been more serious disruptions. In spring 2019, Facebook, Instagram and Whatsapp were offline for almost 24 hours. There were also prolonged problems last December, March and April. In addition to Facebook, Google, YouTube and other platforms also fail again and again, sometimes only in certain regions or for shorter periods of time. This will also be unavoidable in the future: In the end, all it takes is a small human error, and there will always be those.

What can be learned from this?

The global communications infrastructure is in the hands of a few corporations. Three billion people use Facebook's services; for many, the platforms are part of their digital identity. Facebook has even bigger plans: Mark Zuckerberg is working on the so-called Metaverse, a new evolutionary stage of the Internet. Part of life is supposed to take place in a virtual parallel universe that is superimposed on the analog world like a filter. In Facebook's imagination, we are heading toward a future in which people communicate with VR glasses, smart gadgets and avatars. Perhaps this will indeed happen - but the current outage shows that it would not be a good idea to leave control of critical digital infrastructure to a single company.