10 Best Practices to Prevent DDoS Attacks

Distributed Denial of Service (DDoS) attacks spiked in recent years, fueled by the growing reliance on digital infrastructure and the expanding attack surface created by hybrid work environments and always-online services.

According to a report from NETSCOUT, almost 9 million DDoS attacks were launched last year, targeting many of the remote and essential services people were using to make it through the lockdown. Healthcare, remote learning, e-commerce, and streaming services were all hit hard by DDoS attacks, which often interrupted business operations or caused some businesses to fall victim to extortion by the criminal behind the attack.

In many of these cases, attackers were able to mask malicious internet traffic among spikes of legitimate users, making detection significantly harder.

Despite the rise in DDoS attacks, you shouldn’t consider them inevitable. Read on for best practices on how to prevent DDoS attacks.

What is a Distributed Denial of Service (DDoS) Attack?

A distributed denial-of-service (DDoS) attack is an attempt to disrupt the traffic of a targeted server, service, or network by overwhelming it with a flood of Internet traffic. By sending too many requests for information to a server, site, or network, a DDoS can effectively shut down a server, leaving it vulnerable and disrupting an organization’s normal business operations.

These service attacks are particularly effective because they drain server resources, limiting availability for legitimate traffic and causing widespread performance degradation.

How Does a DDoS Attack Work?

A DDoS attack aims to infect a network, by infecting IoT devices with malware, creating botnets that can remotely carry out an attack. The bots in a botnet overload a network by sending malicious traffic to the network’s IP address, eventually resulting in a denial-of-service. DDoS mitigation efforts begin with identifying and blocking this malicious traffic before it overwhelms your systems.

The key challenge is distinguishing between legitimate users and malicious bots, particularly when both are producing high volumes of incoming traffic.

What are the Common Types of DDoS Attacks?

When looking across the scope of DDoS attacks, the most common types of attacks include:

• Volumetric DDoS attacks
• Protocol DDoS attacks
• Application DDoS attacks

Volumetric DDoS Attack

The most common type of volumetric attack is a UDP (User Datagram Protocol) flood, which is often used to send forged UDP packets with false addresses — like the IP address of the victim — to servers for UDP-based applications, generating a flood of reply traffic. These flood attacks can impact a single target or multiple services at once, exhausting network resources and preventing normal operations.

To enhance effective DDoS protection, organizations can use content delivery networks and rate-limiting strategies to absorb and filter out illegitimate requests before they cause disruption.

Rachel Kratch of Carnegie Mellon’s Software Engineering Institute likens it to calling every pizza place in town and ordering several pizzas to be delivered to someone you don’t like. Similarly, ICMP (Internet Control Message Protocol) floods sends false error requests to a target, tying it up so that it can’t respond to normal ones.

Protocol DDoS Attack

Protocol DDoS attacks target the protocols used in transferring data to crash a system. One of the most common is an SYN flood, which attacks the process of making a TCP/IP connection by sending a flood of SYN packets asking the victim to synchronize instead of acknowledging a connection, tying up the system while it waits for a connection that never happens. SYN floods are like telling a knock-knock joke that never ends: knock knock, who’s there, knock knock, who’s there, knock knock…

Protection services such as intrusion prevention systems (IPS) and next-generation firewalls can help detect anomalous patterns in protocol behavior, especially when the volume surpasses thresholds expected from legitimate users.

Application DDoS Attack

Similar to protocol attacks, application-level attacks target weaknesses in an application. These attacks focus primarily on direct web traffic and can be hard to catch because a machine may think it’s dealing with nothing more than a particularly high level of Internet traffic.

These are the most complex form of application-layer attacks because they mimic normal behavior, often executing valid requests designed to consume backend server resources.

Using a web application firewall is one of the most recommended mitigation techniques for this kind of threat, as it can inspect incoming requests and block attempts to exploit application vulnerabilities.

Why is DDoS Prevention Important?

It is essential to implement measures to prevent your network from becoming overloaded or unusable for periods of time, especially when you need it most. A robust approach should involve reducing your attack surface, implementing detection systems, and preparing your organization with best practices to prevent DDoS events.

While implementing a strong mitigation strategy against DDoS attacks can be time-consuming, having that strategy in place can give you greater peace of mind. More importantly, mitigation and catching early warning signs can improve your organization’s cybersecurity posture.

10 Best Practices to Prevent DDoS Attacks

While DDoS attacks come in many shapes and sizes, there are measures you can take to protect your organizations. There is no one-size-fits-all solution to preventing DDoS attacks, but using the following tips in conjunction can lessen the potential for one:

1. Know your network’s traffic
2. Create a Denial of Service Response Plan
3. Make your network resilient
4. Practice good cyber hygiene
5. Scale up your bandwidth
6. Take advantage of anti-DDoS hardware and software
7. Move to the cloud
8. Know the symptoms of a DDoS attack
9. Outsource your DDoS protection for unusual activity
10. Continuously monitor for unusual activity

Let’s take a closer look at the best practices your organization can take to prevent DDoS attacks.

1. Know your network’s traffic

Every organization’s infrastructure has typical Internet traffic patterns — know yours. You’ll have a baseline when you understand your organization’s normal traffic pattern. That way, when unusual activity occurs, you can identify the symptoms of a DDoS attack.

Understanding normal activity will also help differentiate between legitimate usage and early signs of bot traffic or malicious requests aimed at disrupting service.

2. Create a Denial of Service Response Plan

Do you know what will happen when and if a DDoS attack happens? How will your organization respond? By defining a plan in advance, you’ll be able to respond quickly and efficiently when your network is targeted.

This can take some planning; the more complex your infrastructure, the more detailed your DDoS response plan will be. Regardless of your company’s size, however, your plan should include the following:

• A systems checklist
• A trained response team
• Well-defined notification and escalation procedures
• A list of internal and external contacts that should be informed about the attack
• A communication plan for all other stakeholders, including customers and vendors

Include mitigation paths that encompass both network-level and application-layer protection, including rate limiting, content delivery networks, and web application firewalls to handle varied attack vectors.

3. Make your network resilient

Your infrastructure should be as resilient as possible against DDoS attacks. That means more than firewalls because some DDoS attacks target firewalls. Traditional firewalls alone cannot provide effective protection against large-scale DDoS attacks, especially those that rely on sophisticated attack tools designed to mimic legitimate traffic patterns.

Make sure you’re not keeping all your eggs in the same basket. Put data centers on different networks, make sure that not all your data centers are in the same physical location, put servers in different data centers, and be sure that there aren’t places where traffic bottlenecks in your network.

Traffic filtering tools and additional layers of redundancy in DNS servers can further ensure service continuity, even when a target server is under stress.

4. Practice good cyber hygiene

It goes without saying that your users should be engaging in best security practices, including changing passwords, secure authentication practices, knowing to avoid phishing attacks, and so on. The less user error your organization demonstrates, the safer you’ll be, even if there’s an attack.

Employee awareness and well-managed human resources are essential in recognizing social engineering tactics used by threat actors to gain access prior to launching future attacks.

5. Scale up your bandwidth

If DDoS is creating a traffic jam in your network, one way to make that traffic jam less severe is to widen the highway. By adding more bandwidth, your organization will be able to absorb more to absorb a larger volume of traffic. This approach helps maintain normal operations during spikes in traffic and buys time for other mitigation services to activate.

This solution won’t stop all DDoS attacks, however. The size of volumetric DDoS attacks keeps increasing every year. 

6. Take advantage of anti-DDoS hardware and software

DDoS attacks have been around for a while, and some kinds of attacks are very common. Plenty of products are available to repel or mitigate DDoS attacks, including web application firewalls and DNS-level protection tools. Hardening IT infrastructure by adjusting settings, removing unused ports, and enabling timeouts for partly open connections is also important.

7. Move to the cloud

While this won’t eliminate DDoS attacks, moving to the cloud can mitigate attacks. The cloud has more bandwidth than on-premise resources, and cloud providers typically integrate content delivery network capabilities and built-in DDoS mitigation tools for their clients.

8. Know the symptoms of an attack

Your network slows down inexplicably. The website shuts down. All of a sudden, you’re getting a lot of spam. Other common signs or symptoms of a DDoS attack include:

• Slow performance
• High demand from a single page or endpoint
• Outages or crashes
• Poor connectivity
• Any other signs of unusual traffic originating from a single IP address

These symptoms often point to an abnormal strain on your infrastructure. A sudden increase in traffic, particularly from a small set of sources, could signal the beginning of a flood-based attack. In such cases, the system may struggle to handle the excessive traffic, disrupting normal operations and delaying access for legitimate users.

9. Outsource your DDoS protection

Some companies offer DDoS-as-a-Service and specialize in scaling resources to respond to an attack, others bolster defenses, and still, others mitigate the damage of an ongoing attack.

These mitigation services often operate within a well-defined time frame, enabling organizations to recover more quickly and efficiently from an attack event.

10. Continuously monitor for unusual activity

Once you know your typical activity and the signs of an attack, continuously monitor your network for odd traffic. Continuous monitoring allows for the detection of excessive traffic or malicious requests that may precede a larger campaign. This is essential for initiating proactive countermeasures.

However, in addition to baseline traffic monitoring, real-time analysis using mitigation techniques like rate limiting and geo-blocking can proactively reduce risk exposure. Some web application protection solutions integrate with threat intelligence platforms to detect signs of a coordinated attack.

By monitoring traffic in real-time, your organization will be able to spot a DDoS attack when it starts and take action to mitigate it.

How Can SecurityScorecard Help Prevent DDoS Attacks?

Bad actors will always seek out the most vulnerable part of an organization, system, or network. To help monitor your internet traffic, consider a solution that continuously assesses your exposure, giving you an outside-in view of your company’s security.

SecurityScorecard can play a crucial role in helping organizations identify weak points in their external digital footprint that could be exploited in DDoS campaigns. Tracking vulnerabilities across your ecosystem—including open ports, outdated services, and exposed DNS queries—enables faster response to abnormal traffic volumes before they escalate into full-scale attacks.

What sets SecurityScorecard apart is its ability to contextualize traffic anomalies. Not every spike in activity indicates malicious behavior; many businesses experience legitimate traffic spikes due to marketing campaigns, product launches, or seasonal demand. Our platform helps differentiate between expected behavior and unusual patterns suggesting DDoS activity, such as coordinated requests to non-critical endpoints or traffic surges from high-risk geographies.

This distinction becomes especially important when dealing with sudden traffic increases, which are a hallmark of volumetric and protocol-based attacks. By correlating external threat intelligence with observed behavior, SecurityScorecard enables IT teams to react more confidently and avoid over-blocking legitimate requests.

Our easy-to-read security ratings, based on an A–F scale, enable you to provide your leadership with the necessary documentation to prove governance over your vendor risk management program. These ratings also support a proactive approach to cybersecurity by highlighting risk trends and prioritizing remediation efforts that strengthen protection around critical assets.

By layering SecurityScorecard with additional security measures—such as rate limiting, threat intelligence feeds, and threat detection tools—companies can build a more resilient defense strategy. This combined approach improves visibility and responsiveness to malicious behavior while preserving access for legitimate users during times of elevated threat.

Ready to strengthen your defense strategy against DDoS attacks? Start by viewing your organization’s free SecurityScorecard rating and uncover the vulnerabilities attackers see first.

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