The Internet Storm Center reflects on one of most potent DDOS attacks of all time.  This went after the core infrastructure provider rather than the site itself.  Impacting a key Internet support service in this manner created a brief outage for several major companies

Today,  October 21st, marks the one year anniversary of the DDOS attack on Dyn. The attack impacted Dyn’s DNS service, and caused degradation, or inavailability of several popular websites, including Amazon Airbnb, BBC, CNN, Paypal and many others.  The attack was attributed to the Mirai botnet of compromised Internet of Things (IoT) devices, but despite numerous investigations, the attack was not definitively attributed to any one perpetrator or group.  It did, however, highlight the fragility of the underlying Internet infrastructure, and sent a lot of service providers on a quest to shore up their pieces of that infrastructure.