DDoS attacks: What they are and what they can do

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When a Distributed Denial of Service (DDoS) attack occurs, it may do a great deal of damage before you can stop it.

DDoS occur more often than you might expect. According to research conducted by Verisign DDoS Protection Services, nearly 50 million DDoS attacks happen yearly. The number of attacks in Q2 2018 was up 35% compared to the previous quarter. The most common attack type that was mitigated by protective services were User Datagram Protocol (UDP) floods, at 56%. DDoS attacks are also increasing in size and severity — Verisign reported that annually, the average attack peak sizes increased 111%.


Attacks are unpredictable and range in speed and complexity, so it’s vital for more IT professionals to enter the field with cybersecurity knowledge. In fact, according to the U.S. Bureau of Labor Statistics, the demand for computer and IT professionals is anticipated to rise, specifically in cloud computing, collection and storage of big data, and information security.

Because DDoS attacks are so common, becoming an expert can be vital to the success of your career in IT. Let’s take a closer look at what defines a DDoS attack, what happens during an intrusion, and why hackers use them, as well as prevention tips and tricks.

What is a DDoS attack?

According to CSO, an IDG Communications contributing network, a DDoS attack occurs when one or more assailants make it impossible for a business to deliver a service by taking control of servers, devices, services, networks, applications, and more. A DDoS attack is a mission completed by more than one system, while a DOS attack comes from a single system distributing malicious data.

Targets of DDoS attacks tend to be ecommerce websites, online casinos, and businesses that provide online services.

What happens during an attack?

At the beginning of an intrusion, the attackers send data requests to a system in hopes of crashing the server. It overwhelms the bandwidth, CPU, and RAM capacity, which can result in taking entire websites, applications, and businesses off the internet.

Sometimes it can be difficult to tell when a server is under attack, however. Something as minor as a system going down can be the start of a malicious disruption. That said, there are different types of DDoS attacks. Symantec Corporation defines the three categories as such:

  • Volume-based attacks, which take place when one or more assailants send data to create massive traffic to a site to overwhelm the bandwidth of the network.
  • Protocol attacks, which impact the server’s most vulnerable resources.
  • Applications attacks, which focus on exploiting web applications. This is the most sophisticated type of DDoS attack.

Each type of attack is designed to slow down online resources. Generally, the ultimate goal of any attack is to prevent a website from functioning at all, and some assailants may request payment to stop the disruption.

DDoS prevention tips

Anticipating an attack can be your greatest defense mechanism, according to Chris Day, chief cybersecurity officer at data center services provider Cyxtera.

“A disaster recovery plan and tested procedures should also be in place in the event a business-impacting DDoS attack does occur, including good public messaging. Diversity of infrastructure both in type and geography can also help mitigate against DDoS as well as appropriate hybridization with public and private cloud,” Day told CSO.

Understanding how to be quick and flexible in the event of an attack is also critical. Changing tactics in real time for defense will make systems less vulnerable. Another tip for reducing the risk for potential invasions include watching for a secondary attack, as the first could’ve been a mere diversion to exploit even more sensitive information.

Investing in DDoS protection and mitigation services is one of the smartest moves to prevent an attack, John Nye, vice president of cybersecurity strategy at CynergisTek, shared with CSO.

“The No. 1 most useful thing that an enterprise can do — if their web presence is that critical to their business — is to enlist a third-party DDoS protection service,” Nye said. “I will not recommend any particular vendor in this case, as the best choice is circumstantial, and if an enterprise is considering using such a service they should thoroughly investigate the options.”

Lastly, staying vigilant is always key. With more businesses working heavily online, everyone is at risk. As long as you always consider yourself a target and put the right mitigation plan in place, you can reduce your risk of experiencing a DDoS attack.

Learn more about DDoS attack risks at the University of Alabama at Birmingham

Because it’s not feasible to take down botnets indefinitely, more up-and-coming information systems professionals should focus on building a career that’s dedicated to creating a more secure network space to reduce DDoS attacks. The innovative online Bachelor of Science in Information Systems program at the University of Alabama at Birmingham is designed to do just that, enabling you to build a strong foundation in information systems and business while also learning core security concepts to create safer systems.

IS 413 Information Security Management, for example, is a three-credit-hour course that delves deep into the core abstraction of key IS, teaching you the primary meaning and goals of systems protection. You’ll also learn how to manage uncertainty and risk, and understand what it takes to develop prime policies and procedure to secure information systems. By the end of the course, you’ll have the skills and knowledge to audit security breaches and recover software.

Are you ready to start building a future in business and information technology? Schedule an appointment with an enrollment advisor today to begin your journey at the University of Alabama at Birmingham.

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Verisign Distributed Denial of Service Trends Report

DDoS Attack Threats Kaspersky

CSO Online DDoS Explained

Internet Security Emerging Threats

Everything you need to know about DDoS Attacks

Verisign US Security

UAB BSIS Course descriptions

CSO Online Malware Cybercrime DDoS Protection Mitigation tips

BLS Computer and Information Technology