What is a DDoS attack?

A DDoS (Distributed Denial of Service) attack involves overwhelming a computing resource to make it inaccessible to legitimate users.

Unlike a simple denial-of-service (DoS) attack, a DDoS attack simultaneously uses a very large number of machines connected to the Internet.

These devices massively send requests to a single target in order to:

• Saturate your Internet connection
• Deplete its server resources
• Slow down the services
• Cause a complete unavailability

The main objective is generally not to steal data, but to prevent access to a service.

How does a DDoS attack work?

Compromised machine networks

The majority of DDoS attacks rely on networks of infected devices called botnets.

These networks can be composed of:

• Compromised computers
• Infected servers
• Connected cameras
• Connected objects (IoT)
• Vulnerable routers

Cybercriminals remotely control these devices and use them to simultaneously launch millions of requests.

Resource saturation

When the target receives an abnormally high volume of traffic, several problems may arise:

• Very slow response times
• Excessive bandwidth consumption
• CPU saturation
• Memory saturation
• Application deployment

Legitimate visitors can no longer access the service normally.

The main types of DDoS attacks

Volumetric attacks

Volumetric attacks aim to saturate the victim's Internet connection.

The goal is to flood the network with massive traffic.

Examples:

• UDP Flood
• ICMP Flood
• DNS Amplification

These attacks can reach several hundred gigabits per second.

Protocol attacks

These attacks target network resources or intermediary equipment.

They exploit certain characteristics of Internet protocols.

Examples:

• SYN Flood
• Ping of Death
• Fragmentation Attack

They can quickly consume the resources of firewalls and servers.

Application attacks

Application attacks directly target web applications.

Their goal is to excessively solicit certain resource-intensive functions.

Examples:

• HTTP Flood
• Repeated requests to dynamic pages
• API Attacks

These attacks are often harder to detect because they resemble legitimate traffic.

Why are businesses targeted?

Interrupt an activity

A DDoS attack can prevent customers from accessing:

• An online store
• A customer portal
• A SaaS platform
• A professional web service

The interruption can lead to an immediate financial loss.

Damage to reputation

Users expect a service to be available at all times.

Repeated interruptions can harm:

• The brand image
• Customer trust
• The credibility of the company

Extortion

Some criminal groups use DDoS attacks to pressure an organization.

They can demand a sum of money in exchange for stopping the attacks.

Unfair competition

Although rarer, some attacks may be motivated by commercial conflicts or malicious acts aimed at disrupting a competing business.

What are the signs of a DDoS attack?

Several symptoms may indicate that a system is the victim of an attack:

• Website inaccessible
• Slow browsing speed
• Sudden traffic pics
• Abnormal bandwidth consumption
• Repeated server errors
• Frequent disconnections

A regular monitoring of performance often allows for the quick detection of these anomalies.

The consequences of a DDoS attack

Loss of income

For businesses making online sales, every minute of downtime can represent a direct loss of revenue.

Service interruption

Collaborators and clients may lose access to:

• Websites
• Business platforms
• Cloud applications
• Communication services

User experience degradation

Even when the service remains accessible, slowdowns can significantly degrade the visitor experience.

Technical costs

Managing an attack may require:

• Additional resources
• An emergency intervention
• Technical analyses
• Infrastructure optimizations

How to protect against DDoS attacks?

Use an advanced firewall

Modern firewalls allow for filtering out some of the malicious traffic before it reaches the servers.

They can:

• Block certain IP addresses
• Limit excessive requests
• Detecting suspicious behaviors

Implement DDoS protection

Specialized services analyze and filter incoming traffic.

They allow:

• To absorb traffic spikes
• To identify malicious requests
• To maintain the availability of services

These solutions are now essential for exposed infrastructures.

Use a CDN

Content Delivery Networks (CDNs) distribute traffic across multiple infrastructures.

They offer several advantages:

• Server load reduction
• Geographic distribution of traffic
• Additional protection against certain attacks

Monitor the infrastructure

Proactive monitoring allows for quick detection:

• Traffic peaks
• Unusual behaviors
• Attempts of abuse

Monitoring tools facilitate this detection.

Keep systems up to date

Regular updates reduce the risks associated with vulnerabilities that can be exploited in certain attacks.

The role of hosts in DDoS protection

Modern hosts often implement multiple layers of protection:

• Network firewall
• Traffic analysis
• Connection limitations
• Dedicated DDoS protection
• Constant surveillance

These mechanisms help block a large portion of attacks before they affect customers.

When choosing a host, it is recommended to check the protection measures offered.

DDoS and global cybersecurity

An anti-DDoS protection does not replace a comprehensive cybersecurity strategy.

An effective approach must also include:

• Regular backups
• Web Application Firewalls (WAF)
• Antivirus and anti-malware
• Access Management
• Multi-factor authentication
• Surveillance continues

Security always relies on multiple complementary layers.

Common misconceptions about DDoS attacks

“Only large companies are targeted”

Fake.

SMEs, associations, and small online shops can also be targeted.

Attackers often look for less protected targets.

“A DDoS attack allows for data theft”

Not directly.

The main objective is service interruption.

However, some attacks can be used as a distraction during other malicious actions.

“A powerful server is enough to protect oneself”

Fake.

Even a high-performing infrastructure can be overwhelmed without appropriate protection mechanisms.

Why prepare starting today?

The number and power of DDoS attacks continue to increase each year.

The rise of connected devices and botnets allows cybercriminals to have increasingly significant resources.

Companies must therefore anticipate this risk in order to ensure:

• The availability of their services
• The satisfaction of their customers
• The continuity of their activities

A preventive strategy is always more effective than a reaction in an emergency.

Conclusion

DDoS attacks are among the most common threats that internet-connected businesses face. Their goal is simple: to make a service inaccessible by overwhelming it with malicious traffic.

Although they generally do not aim for data theft, their consequences can be significant in terms of availability, revenue, and reputation.

Thanks to a combination of monitoring, DDoS protection, advanced firewalls, and tailored infrastructures, businesses can significantly reduce their exposure to these risks.

Investing in protection against DDoS attacks ensures the availability of services, protects brand image, and provides a reliable experience for users.