A DDoS attack, short for Distributed Denial of Service, is a threatening form of cyberattack that aims to paralyse online services, networks or websites. This is done by flooding the target with a massive amount of internet traffic directed from numerous compromised computer sources. This type of attack is particularly worrying in the modern digital world where online presence and services are critical.

A DDoS attack differs from a simple denial of service (DoS) attack in its size and the use of a distributed network of computers, often referred to as a "botnet". A botnet consists of a large number of internet-connected devices - including computers, smartphones and sometimes even IoT devices - that are infected by malware and remotely controlled to carry out the attack. The attacker controls this network to simultaneously send requests to the target, exceeding its capacity and ultimately disrupting the service.

The effects of a DDoS attack can be devastating. They range from short-term interruptions to long-lasting service outages, which can result not only in financial losses but also damage to the reputation of the affected organisations. Organisations that rely on online services, such as e-commerce platforms, financial institutions or government services, are particularly vulnerable to such attacks.

Combating DDoS attacks is a complex challenge. It requires advanced security measures, such as monitoring network traffic, identifying unusual patterns and reacting quickly to anomalies. It is also important to create redundant network infrastructures to minimise the impact of an attack.

With the increasing networking and growing importance of online services, the frequency and complexity of DDoS attacks is also increasing. It is therefore essential for organisations to prepare for such threats and implement robust security systems to protect their services and data. In a world where digital security is playing an increasingly important role, the defence against DDoS attacks remains an ongoing challenge for IT security experts and companies alike.