A denial-of-service (DoS) attack is a cyber attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host connected to a network. Denial of service is typically accomplished by flooding the targeted machine or resource with superfluous requests in an attempt to overload systems and prevent some or all legitimate requests from being fulfilled.
Types of DoS Attacks
There are two main types of DoS attacks:
- Volume-based attacks: These attacks attempt to overwhelm the target with a large amount of traffic. This can be done by sending a large number of requests to the target, or by sending large files or packets of data.
- Protocol attacks: These attacks exploit vulnerabilities in network protocols to disrupt service. This can be done by sending malformed or invalid packets, or by sending packets that are designed to consume resources on the target system.
DDoS Attacks
A distributed denial-of-service (DDoS) attack is a type of DoS attack that uses multiple compromised systems to attack the target. This makes it much more difficult to defend against, as the attacker can simply add more compromised systems to the attack as needed.
DDoS attacks can be launched for a variety of reasons, including:
- Financial gain: DDoS attacks can be used to extort money from victims by threatening to continue the attack unless a ransom is paid.
- Political or ideological reasons: DDoS attacks can be used to disrupt or censor websites or services that the attacker opposes.
- Cyberwarfare: DDoS attacks can be used as a form of cyberwarfare to disrupt the infrastructure of an enemy nation.
DDoS Mitigation
There are a number of steps that can be taken to mitigate the risk of a DDoS attack, including:
- Use a content delivery network (CDN): A CDN can help to distribute traffic across multiple servers, making it more difficult for an attacker to overwhelm the target.
- Implement rate limiting: Rate limiting can be used to prevent attackers from sending too many requests to the target.
- Use intrusion detection systems (IDSs): IDSs can be used to detect and block malicious traffic.
- Have a disaster recovery plan: A disaster recovery plan can help to minimize the impact of a DDoS attack.