Denial of Service: When a Tidal Wave of Data Crashes

What company doesn’t delight in having lots of user traffic on its website and lots of clicks on its product and service offerings? Sometimes, though, what lies behind that website activity isn’t customer demand or even a human being at all, but rather computers manned by cybercriminals.

Cybercriminals are often capable of generating several hundred gigabits of data per second (see illustration) for the purpose of overwhelming and ultimately disabling a website, server, or an entire network. In such an incident, a company’s customers can no longer access a specific service, which causes revenue losses. Cybersecurity experts call this a denial-of‑service (DoS) attack, which sometimes also involves a ransom demand.  

When cybercriminals harness a whole network of computers to orchestrate their assault – by infecting third-party devices with malware, for example – this is called a distributed denial-of-service (DDoS) attack. DDoS attacks occur very frequently on the internet because the tools that cybercriminals employ to launch them are cheap to acquire and easy to use.   

DDoS attacks can be averted, for instance, by limiting the number of queries, filtering them according to specific criteria, interposing a cloud infrastructure, or by going offline altogether. Leaving the internet, of course, only works if the offering at hand isn’t public – like in B2B applications. SIX, for instance, puts private connections at its clients’ disposal for many services (e.g., Finance IPNet and point-to-point connections). Or alternatively, a novel technology, the Secure Swiss Finance Network (see box), is also now available to make connections even more resistant to cyberattacks.