A DDoS attack, short for Distributed Denial of Service, is a malicious attempt to disrupt the normal operation of a server, network, or online service by overwhelming it with massive amounts of traffic. Unlike a simple DoS attack, which originates from a single source, a DDoS attack is carried out by hundreds or even thousands of compromised devices—collectively known as a botnet—making it significantly harder to block or mitigate.

During a DDoS attack, the targeted system becomes flooded with more requests than it can handle. As the server struggles to respond, legitimate users experience slow performance, connection timeouts, or total service unavailability. For organizations running online platforms, e-commerce websites, cloud applications, or critical infrastructure, the consequences can be severe: downtime, revenue loss, damaged reputation, and security risks.

DDoS attacks come in several types. Volume-based attacks aim to saturate bandwidth by sending massive amounts of traffic such as UDP floods. Protocol attacks exploit weaknesses in network layers using methods like SYN floods or Ping of Death to exhaust server resources. Application-layer attacks mimic real user behavior but overwhelm specific functions like HTTP requests, making them harder to detect and defend against.

Cybercriminals often launch DDoS attacks for various reasons: extortion, ideological motives, competitive sabotage, or simply to cause disruption. Because botnets can consist of compromised PCs, servers, IoT devices, and even smart appliances, attackers can generate enormous traffic volumes at low cost.

To defend against DDoS attacks, organizations typically rely on a combination of techniques such as traffic filtering, rate limiting, anycast routing, blackholing, behavioral analysis, and cloud-based scrubbing centers. Modern DDoS protection platforms can detect anomalies in real time, redirect malicious traffic, and ensure that legitimate users continue accessing the service without interruption.

In essence, a DDoS attack is one of the most common and disruptive forms of cyberattacks on the internet. As online services expand and more devices connect to the web, the scale and sophistication of DDoS threats continue to grow—making proactive protection essential for any business that depends on uptime and reliable network performance.