Denial of Service Attacks

A Denial of Service (DoS) attack is a malicious attempt to disrupt the normal functioning of a targeted server, service, or network by overwhelming it with a flood of traffic. This lesson will cover key concepts, types of DoS attacks, and best practices for prevention and mitigation.

• Denial of Service (DoS): An attack that aims to make a machine or network resource unavailable to its intended users.
• Distributed Denial of Service (DDoS): A type of DoS attack where multiple compromised systems are used to target a single system.
• Botnet: A collection of internet-connected devices, which may include PCs, servers, and IoT devices, that are infected and controlled by malware.

1. Volume-Based Attacks: These attacks include UDP floods, ICMP floods, and other spoofed packet floods.
2. Protocol Attacks: These include SYN floods and Ping of Death, which exploit weaknesses in the protocols.
3. Application Layer Attacks: These target the application layer, such as HTTP floods, to crash web servers.

DoS attacks work by overwhelming the target system with traffic, exhausting its resources, or exploiting vulnerabilities. The following is a typical flow of a DoS attack:

                graph TD;
                    A[Start] --> B{Identify Target};
                    B --> C[Select Attack Method];
                    C --> D[Launch Attack];
                    D --> E{Target Overwhelmed?};
                    E -- Yes --> F[Service Disruption];
                    E -- No --> G[Adjust Attack];
                    G --> D;
            

• Implement rate limiting to control the amount of traffic sent to your server.
• Use firewalls and intrusion detection systems to filter malicious traffic.
• Employ a Content Delivery Network (CDN) to absorb and mitigate attack traffic.
• Regularly update and patch systems to fix vulnerabilities.
• Conduct regular security audits and penetration testing.