Cyber Security

DDoS Attack: The Types, Techniques, and How to Protect from This

Avatar Andrea Abbondanza , 22 Feb, 2024

DDoS attack, or distributed denial-of-service, is an attempt to disrupt a server by flooding it with internet traffic. Once it attacks the system, the system will be vulnerable and slow down, making it inaccessible to legitimate users. This can result in website downtime, loss of revenue, and damage to the reputation of the targeted organization.

This is why understanding DDoS mitigation and its general concept is crucial for any company. To learn more about these cybercriminal activities, continue reading this article!

What is a DDoS attack?

DDoS Attack red enter button black keyboard
DDoS Attack

DDoS attack, or Distributed Denial-of-Service attack, is a cybercriminal activity that targets a server or network by flooding it with excessive traffic from numerous sources, causing it to malfunction.

The aim is to make the system vulnerable, making it difficult for authorized individuals to manage. When the time comes, an attacker can exploit this weakness to gain unauthorized access and potentially cause harm, such as deploying ransomware to encrypt the system’s data and demand payment for its release.

With the increasing popularity of the Internet of Things (IoT) and the growing trend of remote work, the number of devices connected to networks will also rise. Unfortunately, not all IoT devices have strong web server security measures in place, leaving the networks they are connected to vulnerable to cyber attacks. This is why DDoS protection and mitigation are essential to safeguarding networks.

Types of DDoS Attacks

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Types of DDoS Attacks

DDoS attacks are designed to overwhelm systems, making them more susceptible to other malicious cyber activities. These attacks often target specific layers of the OSI model to disrupt network connectivity, resulting in various types of DDoS attacks.

Here are some common types of DDoS attacks:

Protocol Attacks

Protocol attacks specifically target layers 3 and 4 of the OSI model, focusing on the network and transport layers. They work by overwhelming the capacity of web servers, including firewalls so that legitimate traffic cannot get through.

Protocol attacks, such as ICMP floods, SYN floods, and UDP floods, are typical examples. In a SYN flood attack, for instance, the attacker sends an excessive number of TCP handshake requests to the target, each with a fake source IP address. The targeted servers try to respond to each request, but the target becomes overwhelmed since the final handshake never happens.

Application-Layer Attacks

The application layer, which is layer 7 of the OSI model, is responsible for providing network services directly to end-users. The application-layer attacks target vulnerabilities in software applications rather than the network or infrastructure

This layer 7 DDoS attack involves the attacker overloading the victim’s server with more traffic than it can handle. An HTTP flood is a form of application-layer attack that involves sending many HTTP requests to the server, similar to repeatedly refreshing a web browser on multiple computers simultaneously.

Volume-Based or Volumetric Attacks

Volumetric attacks aim to use up all the available internet connection bandwidth between the victim and the rest of the internet. An example of this type of attack is Domain Name System (DNS) amplification. In this attack, the attacker tricks an open DNS server by sending a request for a DNS lookup with the victim’s address.

When the DNS server responds with the DNS record, it sends it to the victim instead of the attacker, effectively amplifying the attacker’s original small request.

How Does a DDoS Attack Work?

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How does a DDoS attack work?

In simple terms, a DDoS attack overwhelms the targeted network or server with fake internet traffic, making it unresponsive to legitimate requests. This attack can only occur when a device is connected to a web.

These networks are made up of computers and other devices, like IoT devices, that have been infected with malware. This malware lets an attacker control these devices from a distance. Each infected device is called a “bot” or “zombie,” and a group of these bots is called a “botnet.”

Once a botnet has been established, the attacker can control it by sending remote instructions to each bot to carry out a DDoS attack on the targeted server. When the botnet identifies the targeted server, the bots will send a flood of requests to the victim’s IP address, overwhelming it and causing a DoS attack on normal traffic.

How to Identify a DDoS Attack

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How to Identify a DDoS attack

When a DDoS attack targets a device or system, it receives excessive requests that can overload the system’s traffic. However, there are specific indicators that suggest a network is under a traffic attack. Here are some signs to determine if a server is under attack:

  • The abnormal numbers of traffic coming from a single IP range and IP address.
  • A sudden increase in requests to a specific page or endpoint without a clear explanation.
  • There is a lot of traffic from users with the same behaviours, like device type and geolocation.
  • Unusual traffic behaviours like sudden spikes in activity during unusual times of the day or patterns that seem unnatural.

DDoS Threats

Red background giving signs for DDoS threats
DDoS Threats

DDoS traffic attacks can have the worst impact on a company’s server. They aren’t just temporary server issues; they can cause lasting damage. They might harm the server’s hardware, expose sensitive data, and disrupt business operations.

Here are the general threats once a system receives this DoS attack:

Operational Disruption

A DDoS attack compromises the system’s resilience, making it vulnerable to additional cyber security threats. This situation can render an organization unable to maintain regular operations, disrupting operations. They may be unable to carry out essential functions, which could reduce customers’ ability to use its services.

Financial Losses

If an organization’s system is attacked, its data could be lost or stolen, requiring spending more money to recover and prevent further damage. These attacks can also cause the system to be unavailable, reduce how much work can be done, and harm the organization’s reputation, all of which can lead to more expenses.

Reputational Damage

A DDoS attack can render a website inaccessible or cause it to function poorly, which can damage the organization’s reputation. For example, imagine a customer attempting to access a website to make a purchase or gather information but encountering error messages or slow loading times due to attack traffic. This frustrating experience may drive the customer to explore a competitor’s website instead.

DDoS Protection Techniques

Two hands typing in a keyboard and trying to protect their system from DDoS attacks
DDoS Protection Techniques

Once you understand the types of DDoS attacks and their impact on a system, it is essential to learn how to protect against them. Here are some techniques you can use to prevent these attacks.

Reduce Attack Surface Area

Preventive actions are crucial to reduce the likelihood of attackers targeting your system. One technique is to minimize the surface area that can be attacked, which limits the options for attackers and enables you to concentrate your protective measures in one place.

It’s best to make sure that the attacker won’t have much space to exploit vulnerabilities. One way to do this is by restricting access to our application and resources, only allowing communication through expected ports, protocols, and applications. This helps to minimize the potential entry points for attackers, allowing us to focus our efforts on preventing attacks.

Plan for Scale

There is a scale to measure the size of DDoS attacks. If you encounter large-scale volumetric DDoS attacks, you need to focus on two main factors: bandwidth capacity and server capacity.

When considering bandwidth capacity, ensure your hosting provider has redundant Internet connections for high-traffic volumes. Placing resources near users and major Internet hubs helps maintain availability during traffic surges. Content Distribution Networks (CDNs) and smart DNS services can also improve access by distributing content from nearby servers.

For server capacity, it’s essential to scale resources as a DDoS attack may overwhelm servers quickly. This can be done by using larger servers or those with advanced networking features. Load balancers can also help distribute traffic to prevent any server from overloading.

Know what is normal and abnormal traffic

When we see a lot of traffic going to a computer, the first thing we do is limit how much traffic it can handle to avoid problems. This is called rate limiting.

A more advanced way to protect against attacks is to accept traffic that looks real only by checking each piece of data. To do this, we need to know what real traffic looks like for that computer and compare each piece of data to that. This helps us spot fake data that attackers might try to send, known as “spoof.”

Deploy Firewalls for Sophisticated Application attacks

One effective strategy is to employ a Web Application Firewall (WAF) to protect against attacks like SQL injection or cross-site request forgery, which target vulnerabilities in your application.

Because these attacks can be complex, it’s essential to develop tailored defences against malicious requests quickly. These requests may try to mimic legitimate traffic or originate from suspicious IP addresses or unexpected locations. Sometimes, seeking expert assistance to analyze traffic patterns and devise specialized protections in real time is beneficial.

Frequently Asked Questions

What happens when you get a DDoS attack?

During a DDoS attack, your website is bombarded with so much traffic that it becomes slow or inaccessible. This flood of traffic, orchestrated by a botnet, aims to overwhelm your site’s resources.

Is a DDoS attack harmful?

Yes, a DDoS attack can cause harm by disrupting the normal operation of websites or online services. This attack floods the targeted system with excessive traffic, causing it to become slow or entirely inaccessible to genuine users.

Why do people do DDoS attacks?

DDoS attacks happen for different reasons. Some people do it to make money by threatening others; some do it to promote causes; some do it to harm competitors; some for cyber warfare between countries; and some to create chaos or show off their hacking skills. All these underline the importance of data security.


For a company, avoiding a DDoS attack is crucial because it not only disrupts the affected system but also leads to financial losses, damages reputation, and causes inconvenience to customers. This is why learning about it will help you go through it, and you’ve done it.

If you want to discuss more about various attacks or need security help for your system and data, contact Fluxgate today!