For IT professionals, managed service providers (MSPs), and business leaders, understanding the mechanics and mitigation strategies of DDoS attacks is essential for maintaining uptime and protecting sensitive data.
This guide will walk you through the essentials of DDoS attacks, detailing how they work, their various types, how they’re mitigated, and why staying informed is critical.
What Is a DDoS Attack?
At its core, a distributed denial-of-service (DDoS) attack is a cyberattack designed to disrupt the availability of a target service, website, or network. Attackers achieve this by overwhelming target systems with a flood of malicious traffic or connection requests.
Unlike a traditional denial-of-service (DoS) attack, which originates from a single source, DDoS attacks leverage a network of compromised devices, often referred to as a botnet. These devices—anything from computers to IoT devices like smart thermostats—are infected with malware and remotely controlled by attackers to launch large-scale traffic surges.
The result? Legitimate users are blocked from accessing the targeted services, leading to significant downtime and often causing financial losses or operational disruptions.
How Does a DDoS Attack Work?
A DDoS attack typically starts with the creation of a botnet—a network of compromised devices infected with malware. Once the botnet is assembled, the attacker sends commands to these devices, instructing them to bombard a specific target with traffic.
This incoming flood of requests overwhelms the target server or network, surpassing its available resources, such as bandwidth, memory, or compute power. Normal users trying to access the website, app, or service are unable to do so, as the system becomes overloaded and unresponsive.
One of the key challenges in identifying such an attack lies in its deceptive nature—attack traffic can look like legitimate user traffic, making it difficult for systems to differentiate between the two.
Types of DDoS Attacks
There are several types of DDoS attacks, each targeting specific aspects of network or system performance. They can generally be divided into three major categories based on their focus.
Application Layer Attacks (Layer 7)
Application-layer attacks target the layer that handles user interactions with online services. These attacks aim to exhaust system resources by overwhelming web servers or applications with HTTP or HTTPS requests.
For example, an HTTP flood attack involves sending repeated requests to a website, similar to refreshing a page nonstop. Although each individual request looks legitimate, the combined volume overwhelms the server, leading to downtime.
Protocol Attacks (State-Exhaustion Attacks)
These attacks exploit vulnerabilities in network protocols, specifically layers 3 (network) and 4 (transport) of the OSI model. An example is the SYN flood, where attackers bombard a server with TCP connection requests without completing the handshake, causing the server to allocate resources unnecessarily. Over time, these incomplete connections overwhelm the server’s capacity, disrupting operations.
Volumetric Attacks
Volumetric attacks aim to congest the available bandwidth of the target by sending massive amounts of traffic. Common examples include DNS amplification, where attackers amplify small DNS queries into large responses directed at the target, consuming all bandwidth and making services inaccessible.
DDoS Attack Mitigation Strategies
Mitigating a DDoS attack requires a multi-layered approach that includes detection, defense, and recovery strategies. Key tactics include traffic differentiation to separate malicious traffic from legitimate users, as well as using tools to analyze patterns such as IP addresses and user behavior. Solutions like Adlumin MDR enhance this approach with 24/7 monitoring, AI-powered analytics, and real-time threat isolation. During a DDoS attack, it isolates malicious traffic in real time, protecting your operations while neutralizing the threat. It also provides detailed insights to ensure compliance and keep your network secure.
Another common technique is rate limiting, where the number of requests a server will accept within a set timeframe is capped. This prevents attackers from overwhelming the system, although it is typically used in conjunction with other strategies. Blackhole routing, or null routing, is a more extreme measure that redirects all incoming traffic—including legitimate requests—into a « black hole » to stop the attack, though it also blocks genuine users.
Web application firewalls (WAFs) add another layer of protection by analyzing incoming HTTP requests and filtering out malicious traffic before it can reach the server. For larger-scale attacks, anycast network distribution proves effective by spreading incoming traffic across multiple servers in a wide network, reducing the strain on any single server. Finally, ongoing risk assessments are crucial for proactively identifying vulnerabilities and preparing organizations for potential attacks. These audits enable teams to prioritize defense mechanisms for the most critical areas, ensuring a more robust and resilient system against DDoS threats.
Why IT Teams and MSPs Should Pay Attention
For IT professionals and MSPs, understanding DDoS attacks isn’t optional—it’s critical for ensuring uptime and protecting clients’ operations. These professionals are typically responsible for managing and securing key platforms that drive essential business functions. A DDoS attack can disrupt customer logins, online purchases, cloud services, and more, undermining trust in your IT capabilities.
By understanding DDoS types, recognizing the signs, and developing tailored mitigation strategies, you’ll ensure services remain available and clients retain confidence in your ability to safeguard their business operations.
Don’t Be Caught Unprepared
DDoS attacks may be growing in size and sophistication, but with the right knowledge and tools, they’re not insurmountable. For IT teams, MSPs, and business owners, staying ahead of these threats ensures continuity, reliability, and peace of mind.
Whether you’re performing routine risk assessments or implementing advanced firewalls, it’s crucial to adopt proactive measures to recognize and respond to these challenges promptly. After all, when it comes to cybersecurity, it’s always better to build the dam before the flood arrives.
