Before and After Networks 9: When Things Break

Failure used to be local. That was not a design achievement — it was a side effect of disconnection.

Before networks, problems and outages often took longer to fix, but their effects were usually limited to one place or one organization. A crashed system was somebody’s bad day, not everybody’s.

Now, because systems are connected, one outage, software failure, or cyberattack can affect millions of people at once. A single bad update can ground airlines and close pharmacies on the same morning.

The links that share resources also share failures — coupling is the price of connection. Resilience used to come free with isolation; now it has to be designed in deliberately, with redundancy, backups, and people who think about failure for a living. This is a large part of why network engineers exist.