DoS and DDoS Network Attacks

A denial-of-service (DoS) attack consists of deliberately flooding a system with fake traffic, preventing legitimate users from accessing its services. Its most dangerous variant, a distributed denial-of-service (DDoS) attack, amplifies the damage by inundating systems from multiple network-connected devices (botnets). To sum up:

• Denial-of-service (DoS) attack: Overwhelms a system with fake traffic from a single source.
• Distributed denial-of-service (DDoS) attack: Amplifies the attack’s impact through botnets: networks of infected devices (including IoT devices, routers, and cameras) that send millions of simultaneous requests.

These attacks have evolved by leveraging networks of compromised devices (including IoT devices such as IP cameras or home routers), which send millions of simultaneous requests to overwhelm target resources.

The main goal of a DoS or DDoS attack is service disruption:

• Loss of access to a company’s website or email system.
• Total failure of online systems or services.
• Network saturation that prevents daily operations.

Although they are usually the result of a malicious action, these attacks can also occur due to configuration or technical errors. Nevertheless, intended attacks can result in multimillion-dollar losses, affect a company's reputation, and open the door to other threats (such as ransomware or data exfiltration).

In some cases, attackers try to extort companies, demanding payments to stop the attack. In other cases, they use network attacks as a distraction to carry out other more complex cyberattacks in the background.

DDoS attacks are usually carried out through botnets: networks of infected devices that operate in a coordinated manner. Each zombie device  sends massive requests to the victim’s server until its bandwidth or processing capacity collapses.

A famous example was the 2016 attack against Dyn, a DNS provider, which temporarily brought down services such as Twitter, Netflix, Amazon, or The New York Times.

Currently, attackers also use poorly secured IoT devices to maximize the scope of their attacks. Common techniques include:

• UDP flood: Flooding of a host with UDP packets.
• SYN flood: TCP resource exhaustion.
• HTTP flood: Massive simulated legitimate network traffic.
• Volumetric attacks: They saturate network bandwidth by sending massive amounts of data (e.g., DNS amplification).
• Protocol attacks: They exploit weaknesses in protocols such as TCP, UDP, or ICMP to consume server resources.
• Application-layer attacks: They target web applications with seemingly legitimate traffic (this makes them more difficult to detect).

These attacks prevent the targeted server from accepting new requests, directly affecting business operations.

Big Data analytics has become a key tool for defense against DDoS attacks. Instead of manually inspecting traffic, modern systems analyze patterns of millions of data points in real time to detect behavioral anomalies on the network.

The benefits of Big Data in cybersecurity include:

• Real-time monitoring of millions of IP addresses.
• Automated analysis of anomalous traffic by geolocation, ports, and protocols.
• Machine learning algorithms that identify suspicious IP addresses and block emerging attack patterns.

Modern systems also enable you to apply geo-blocking when anomalous patterns are detected in certain regions, or create custom rules based on historical traffic behavior.

As DDoS attacks become more complex and persistent than ever, defensive strategies have evolved into smarter, more automated solutions. Reactive measures are no longer enough. Proactive prevention and real-time adaptability are essential to ensure service continuity.

• Use of DDoS scrubbing centers that filter malicious traffic in the cloud before it reaches the target system. These centers detect, analyze, and eliminate unwanted traffic through advanced deep inspection techniques, enabling only legitimate connections to reach their destination.
   
• Hybrid (on-premise and cloud) solutions that combine local protection devices with automatic redirection of suspicious traffic to scrubbing centers in the cloud. This approach reduces response latency and helps absorb and mitigate large-scale attacks.
   
• Incorporation of SDN (Software Defined Networking) and ML (Machine Learning) for early detection and automated mitigation. These technologies enable you to create a dynamic, real-time response, adjusting network behavior based on observed and learned traffic patterns.

These advanced solutions represent a new standard in DDoS attack protection, where intelligence and automation work together to contain attacks before they cause real damage to the business.

In addition to malicious traffic, the manipulation of routing protocols such as Border Gateway Protocol (BGP) has opened new avenues to enhance DDoS attacks and compromise the availability of services on the Internet. Incorrect routing can be as effective as a traditional volumetric attack, but much more difficult to detect.

BGP hijacking can redirect massive traffic or block critical routes, thus amplifying a DDoS attack. By announcing incorrect routing information from compromised autonomous systems, attackers can redirect traffic to their own servers or create disruptions in key services.

The number of global BGP incidents has decreased (only 3 global BGP route leaks and not a single BGP hijack), largely thanks to the deployment of RPKI (Resource Public Key Infrastructure). This technology validates the legitimacy of route announcements, helping to prevent accidental or malicious hijacks.

Even so, targeted kidnappings remain active, especially in financial contexts. A recent example is the KlaySwap incident, where a BGP attack was used to redirect traffic and steal cryptocurrency assets. This demonstrates how this technique could be used surgically with lucrative aims.

Although statistics are improving, BGP hijacking remains a latent threat. Especially when it is combined with DDoS attacks to bypass traditional security measures. Today, protecting global routing is an integral part of a robust cybersecurity strategy.

Key recommendations:

• Implement firewalls and WAFs (Web Application Firewalls) to filter malicious traffic.
• Purchase specialized DDoS attack mitigation services (such as Cloudflare, Akamai, or advanced cloud services).
• Segment internal networks to stop domino effects.
• Monitor traffic in real time with AI-powered tools.
• Implement redundancy measures so that if a service fails it does not affect the entire system.

We also recommend you purchase DDoS scrubbing services, which filter malicious traffic in real time before it reaches the destination server, enabling only legitimate connections to pass through the network.

DoS and DDoS attacks are more sophisticated, frequent, and harmful than ever. They affect businesses of all sizes, and their impact is not only economic but also reputational and operational. Investing in proactive cybersecurity is key to ensuring business continuity.