What just happened? Microsoft has revealed that it was able to mitigate a 2.4 terabits per second (Tbps) DDoS attack targeting one of its customers by using the company’s Azure cloud service. In doing so, the tech giant succeeded in fending off one of the biggest distributed denial of service attacks on record.
Amir Dahan, senior program manager at Azure Networking, explained in detail how the attack that took place in late August was carried out. The attack was made up of around 70,000 “sources” from the Asia-Pacific region, including Malaysia, Vietnam, Taiwan, Japan and China. The United States was also mentioned as a country involved to some extent.
The massive DDoS attack was delivered in three short bursts over a period that lasted more than 10 minutes. The first wave was strong at 2.4 Tbps, the second at 0.55 Tbps and finally the third at 1.7 Tbps.
A DDoS attack aims to submerge a website or service with such high traffic that it simply cannot handle it, effectively forcing the target to log off. They are carried out by a network made up of machines infected with malware, allowing an attacker to control them remotely.
Despite the attack’s record size, Microsoft has confirmed that it cannot penetrate their infrastructure thanks to its distributed mitigation capability, which can “scale massively to absorb the largest volume of DDoS threats.” Azure’s protection platform is capable of supporting dozens of terabits of DDoS attacks without affecting customers.
Dahan said the biggest DDoS attack before this announcement was a 1 Tbps attack that occurred last year in the third quarter of 2020. This year, although it reported a 25% increase in the number attacks compared to Q4 2020, Microsoft Azure cloud platform did not experience a DDoS attack exceeding 625 Mbps in H1 2021.
Preventing the second biggest DDoS attack on record isn’t too bad a selling point for potential Microsoft customers. But the distinction of the largest averted attack on record belongs to Google, which mitigated a 2.54 Tbps hit in 2017.