DDoS Attack Meaning
A Distributed Denial-of-Service (DDoS) attack is a cyberattack in which an attacker overwhelms a server, website, or online service with excessive traffic. Because the server is flooded with fake or malicious requests, legitimate users are unable to access the service. The motivation behind DDoS attacks varies widely—some attackers act out of personal revenge or activism, while others are driven by financial gain.
In many situations, competitors may use DDoS attacks to disrupt a rival company’s online operations and gain an unfair advantage. Extortion is also common: attackers overload a business’s servers, sometimes pairing the attack with ransomware or hostageware, and demand payment to restore normal functionality.
Difference Between DoS and DDoS
The primary difference between a DoS and a DDoS attack is the scale at which the attack is launched.
A DoS (Denial-of-Service) attack is carried out from a single device targeting a single system.
A DDoS (Distributed Denial-of-Service) attack involves multiple compromised systems (often part of a botnet) working together to overwhelm a target.
Below are some key differences:
Aspect | DoS (Denial-of-Service) | DDoS (Distributed Denial of Service) |
Source of Attack | Single system | Multiple systems attacking at once |
Detection | Easy to detect and block | Harder to detect due to distributed sources |
Speed of Attack | Slower, limited by one machine | Much faster and more powerful |
Traffic Volume | Low traffic volume | Extremely high traffic volume |
Attack Method | Tools or scripts from one device | Botnets controlled by a C&C server |
Traceability | Easier to trace | Difficult to trace due to distributed nature |
Types of DDoS Attacks
Below are four common types of DDoS attacks:
1. Volumetric Attacks
These attacks overload the target’s bandwidth by sending massive amounts of traffic through a botnet. The overwhelming traffic leads to network congestion and causes the service to crash or become unreachable.
2. Protocol Attacks
Protocol attacks exploit weaknesses in network protocols such as TCP. Attackers initiate but do not finish processes like the TCP handshake, causing server ports and resources to remain tied up until the server becomes unresponsive.
3. Application Layer Attacks (Layer 7 Attacks)
These attacks target the application layer by sending requests that appear legitimate. They gradually exhaust server resources, making them difficult to recognize and stop. Common targets include login pages, search functions, and HTTP requests.
4. Fragmentation Attacks
Fragmentation attacks manipulate the process of IP packet fragmentation. Attackers send malformed or incomplete packet fragments that the server cannot reassemble, consuming processing power and disrupting network traffic flow.
How DDoS Attacks Work
A DDoS attack takes advantage of the operational limits of online systems. For example, websites and servers can only manage a specific number of requests per minute. When this threshold is exceeded—whether due to real spikes in traffic (like Black Friday sales) or malicious flooding—the service slows down or crashes.
In a DDoS attack, this overload is intentional. Attackers send massive amounts of fake requests from multiple devices, overwhelming the target’s:
Web Applications – limited by how many simultaneous requests they can process
Networks – limited by available bandwidth
Servers – limited by maximum connections and CPU/RAM capacity
Once these limits are exceeded, legitimate users can no longer access the service, leading to a denial-of-service state.
How to Protect Against a DDoS Attack
1. Act Quickly
Early detection is critical. Businesses should use DDoS mitigation tools capable of recognizing unusual traffic spikes in real time.
2. Configure Firewalls and Routers
Ensure firewalls and routers are properly configured to filter out illegitimate traffic. Regular updates and security patches are essential to defend against new threats.
3. Utilize Artificial Intelligence
AI-powered security tools can analyze traffic behavior patterns and automatically block suspicious activity before it escalates into a full-scale attack.
4. Secure IoT Devices
IoT devices are often weak points and can be hijacked into botnets. Keep firmware updated, install security software, and disable unnecessary features to prevent exploitation.
Conclusion
A robust and proactive security strategy is essential to safeguard against DDoS attacks. By combining advanced defensive tools, timely updates, and quick incident response, businesses can significantly reduce the risk and maintain consistent access to their online services.