While the internet itself was first envisioned as a way of enabling robust, fault-tolerant communication, the global routing infrastructure that underlies it is relatively fragile.
A simple error like the misconfiguration of routing information in one of the 7,000 to 10,000 networks central to global routing can lead to a widespread outage, and deliberate actions, like preventing traffic with spoofed source IP addresses, can lead to distributed denial of service (DDoS) attacks.
