20 DDoS Interview Questions and Answers

A distributed denial-of-service (DDoS) attack is a type of cyber attack in which a large number of requests are made to a server in an attempt to overload it and cause it to shut down. DDoS attacks can be very damaging to a company, so it is important for employers to ensure that their potential employees are familiar with the concept and how to prevent and mitigate such attacks. In this article, we will discuss some common DDoS interview questions that you may encounter.

DDoS Interview Questions and Answers

Here are 20 commonly asked DDoS interview questions and answers to prepare you for your interview:

1. What is DDoS?

DDoS stands for Distributed Denial of Service. It is a type of cyber attack that attempts to make a system or network unavailable by flooding it with requests from multiple computers. This can cause the system to crash or become overloaded and unable to respond to legitimate requests.

2. What are the main categories of DDoS attacks?

There are four main categories of DDoS attacks:

1. Volume-based attacks: These attacks aim to overload the network or server with a large amount of traffic.

2. Protocol attacks: These attacks exploit weaknesses in the protocol stack, such as SYN or DNS floods.

3. Application attacks: These attacks target specific applications, such as a WordPress site or an ecommerce site.

4. Hybrid attacks: These attacks combine two or more of the above categories to create a more powerful attack.

3. Why do companies use DDoS attack protection to safeguard against DDoS attacks?

DDoS attack protection is used to safeguard against DDoS attacks for a number of reasons. First, DDoS attacks can be incredibly costly, both in terms of the resources required to mount the attack and in terms of the damage that can be done to a company’s reputation. Second, DDoS attacks can be difficult to defend against, and even a small DDoS attack can have a significant impact on a company’s operations. Finally, DDoS attacks are often used as a way to distract from or cover up other malicious activity, such as data breaches. By protecting against DDoS attacks, companies can help ensure that their systems are not used as a launching point for other attacks.

4. What’s your understanding of a botnet? How does it work?

A botnet is a network of computers that have been infected with malware and can be controlled remotely by an attacker. The attacker can use the botnet to launch attacks, such as denial of service attacks, against other computers or networks.

5. Can you explain what a reflection attack is and how it works?

A reflection attack is a type of distributed denial of service (DDoS) attack in which the attacker spoofs the source IP address of UDP packets sent to a reflector server, resulting in the reflector server sending a flood of traffic to the spoofed address. This amplifies the attacker’s traffic and makes it much harder to trace the source of the attack.

6. Can you explain what a DNS amplification attack is?

A DNS amplification attack is a type of distributed denial of service (DDoS) attack in which attackers exploit vulnerabilities in Domain Name System (DNS) servers to amplify the amount of traffic directed at a target system. This is done by sending DNS requests with spoofed source IP addresses to open DNS resolvers, which then respond with DNS responses that are much larger than the original request. The attacker can then use these responses to flood the target system with traffic, causing it to become unavailable.

7. What is the difference between SYN flood attacks and TCP flood attacks?

A SYN flood attack is a type of denial of service attack in which an attacker sends a large number of SYN requests to a server in an attempt to overload it. A TCP flood attack is a type of denial of service attack in which an attacker sends a large number of TCP packets to a server in an attempt to overload it.

8. Do you know anything about HTTP flooding and HTTPS flooding?

HTTP flooding is a type of DDoS attack that involves sending a large number of HTTP requests to a server in an attempt to overload it and cause it to crash. HTTPS flooding is a similar attack that uses HTTPS requests instead of HTTP requests.

9. What are some common examples of application layer attacks?

Application layer attacks are those that target a specific application or service running on a server. Common examples include attacks that exploit vulnerabilities in web applications, such as SQL injection or cross-site scripting. These attacks can be very difficult to detect and defend against, since they often mimic normal traffic patterns.

10. Can you explain what a Smurf Attack is?

A Smurf Attack is a type of Distributed Denial of Service (DDoS) attack that works by flooding a target with Internet Control Message Protocol (ICMP) echo request packets. These packets are sent with a spoofed source IP address, which makes it appear as if they are coming from the target itself. The target then responds to these requests, resulting in a flood of traffic that can overwhelm the target and cause it to become unavailable.

11. What is a zero-day or zero-hour attack?

A zero-day or zero-hour attack is an attack that takes advantage of a previously unknown vulnerability in a system or application. These types of attacks can be particularly difficult to defend against because there is no known way to patch the vulnerability. In many cases, the only way to defend against a zero-day attack is to have strong security measures in place to detect and block the attack before it can do any damage.

12. What are some methods that can be used to prevent DDoS attacks?

Some methods that can be used to prevent DDoS attacks include rate limiting, which can help to control the amount of traffic that is allowed to hit a server, and using firewalls to block certain types of traffic. Additionally, keeping your software and systems up to date can help to prevent vulnerabilities that could be exploited in a DDoS attack.

13. What are some advantages of using cloud computing services as a method for preventing DDoS attacks?

One advantage of using cloud computing services to prevent DDoS attacks is that cloud providers can offer more robust infrastructure and security than most organizations can afford to implement on their own. Additionally, cloud providers can offer DDoS protection as a service, which can be more cost-effective than building and maintaining your own DDoS protection infrastructure.

14. What are mitigation techniques that can be used to prevent attacks from occurring?

Some mitigation techniques that can be used to prevent DDoS attacks from occurring are to rate limit traffic, use firewalls, and implement intrusion detection systems.

15. What are some testing tools available for validating applications’ ability to withstand DDoS attacks?

There are a few different tools available for testing an application’s ability to withstand DDoS attacks. One is called “DDoS Hammer,” and it is a tool that can be used to simulate different types of DDoS attacks. Another tool is called “DDoS-Deflate,” and it is a tool that can be used to help mitigate DDoS attacks.

16. What are some ways in which administrators can detect DDoS attacks on their sites?

There are a few different ways that administrators can detect DDoS attacks on their sites. One way is to monitor traffic levels and look for sudden spikes. Another way is to look for patterns of requests that seem to be coming from multiple computers at the same time.

17. What are some limitations of DDoS attack prevention software?

One of the primary limitations of DDoS attack prevention software is that it can be difficult to distinguish between legitimate traffic and malicious traffic. This can lead to false positives, where the software blocks legitimate traffic, or false negatives, where the software fails to block malicious traffic. Additionally, DDoS attack prevention software is often only effective against a specific type of DDoS attack, meaning that if an attacker uses a different type of attack, the software may not be able to prevent it.

18. What should enterprises look for when evaluating DDoS attack protection solutions?

When evaluating DDoS attack protection solutions, enterprises should look for a few key features. First, the solution should be able to identify and track DDoS attacks in real-time. Second, it should be able to provide protection against a variety of DDoS attack types, including SYN floods, UDP floods, and ICMP floods. Finally, the solution should be able to scale up or down as needed to meet the changing needs of the enterprise.

19. What are the pros/cons of detecting DDoS attacks vs preventing them?

The main pro of detecting DDoS attacks is that it can give you information about what kind of attack is happening and who is behind it. This can be helpful in terms of preparing for future attacks and improving your overall security. The main con of detection is that it can be difficult to do in real-time, and so you may not be able to take action to prevent the attack from happening. The main pro of prevention is that it can stop an attack before it starts, and so can save you a lot of time and effort. The main con of prevention is that it can be difficult to implement, and so you may not be able to stop all attacks.

20. Who is responsible for cleaning up after a DDoS attack has occurred?

The organization that was attacked is responsible for cleaning up the aftermath of the attack. This includes identifying and repairing any damage that was done, as well as taking steps to prevent future attacks.