DoS vs DDoS: 4 Differences and How To Prevent the Attacks

Do you understand the difference between DoS vs DDoS or why it even matters?

The details of Internet security matter. Often, the difference between a malicious website breach and an attempted hack that was averted is a small, overlooked detail. That’s why it’s important to understand the differences between a DoS vs DDoS attack.

What exactly is a DoS attack? And how does it differ from a DDoS attack?

DoS attacks are denial of service attacks. This type of cyberattack uses a remote computer to flood a chosen server with UDP (User Datagram Protocol) and TCP (Transmission Control Protocol) packets.

DDoS attacks happen when more than one system targets a single server with a DoS attack. When this happens, the network that’s been targeted gets slammed with UDP and TCP packets from many different locations.

As you can see, this means that all DDoS attacks are DoS attacks. However, not all DoS attacks are DDoS attacks.

Denial of Service Attacks Can Ruin a Business

DoS (Denial of Service) and DDoS (Distributed Denial of Service) attacks are at the forefront of cybersecurity threats that all modern businesses and organizations face. In fact, there are few other types of security threats that cost more to resolve than when a successful DoS attack happens.

Recent studies regarding cybersecurity show that the price tag for digging out of a successful DDoS attack will average anywhere between $20,000 – 40,000 per hour.

Yes, per hour.

This makes it difficult for even the largest organizations to overcome such attacks.

When a DoS attack succeeds, it not only puts your site out of commission for substantial periods of time but can also cause major system malfunctions. And every single minute you’re out of commission means lost revenue and costly recovery processes.

In this guide, we’ll walk you fully through the differences between DoS vs DDoS attacks. Then, we’ll show you exactly what you need to do to prevent them from happening to you as a WordPress site owner.

What’s a DoS Attack?

As stated in the intro, DoS attacks are denial of service attacks. This type of cyberattack uses a remote computer to flood a chosen server with UDP and TCP packets.

When this attack happens, all service gets shut down. This is because the packets that are flooding through over the network are overloading the capabilities of the server. Because of this, the server becomes unavailable to other users and devices throughout the network that’s under attack.

DoS attacks can be used in several different ways, including:

Buffer Overflow Attacks

This is the most common DoS attack. Under a buffer overflow attack, that cyber attacker overloads the address of a network with “traffic,” which puts the network out of use.

Ping of Death or ICMP Flood

This type of attack takes misconfigured or unconfigured network devices. It uses them to send out spoof packets that ping every single computer on the network that’s been targeted.

This is why it’s often referred to as the Ping of Death (POD) attack.

SYN Flood

These attacks send off network connection requests to a server, then don’t complete the process. The network then becomes overly inundated with a bombardment of connection requests, which disallows a real user to connect to the network.

Teardrop Attack

When a teardrop DoS attack happens, the attack will send IP data packet fragments directly to a network. Then, the network tries to recompile the data packet fragments into original packets.

While running this process, the system becomes exhausted and crashes. This is because the fields in the data packet were intended to confuse the server by being impossible to put back together.

Unfortunately, DoS attacks can be coordinated pretty easily. Because of this, they’ve become one of the top threats that businesses have to face. They’re simple, yet highly effective attacks that can absolutely devastate people and organizations that are targeted.

In fact, one DoS attack can put a business out of commission for days or weeks.

And that means a lot of lost revenue.

What’s a DDoS Attack?

Most often, a modern DoS attack will come in the form of a DDoS attack.

During DDoS attacks, more than one system targets a single server, or system, simultaneously with fake traffic. 

This process makes it easier for the attacker to put the targeted system offline because the attacker is using multiple machines. It can be very difficult for the attack victim to accurately pinpoint where the attack is coming from.

The first major difference between a DoS vs DDoS attack is that a DDoS attack makes things much more difficult to recover from.

The vast majority of the time, the systems an attacker uses to execute a DDoS attack have been compromised. This allows an attacker to execute remote attacks by using these slave computers (also referred to as bots).

The bots form their own network of connected devices, referred to as a botnet. The botnet is managed by an attacker with a command and control server. This server gives the cyber attacker the ability to coordinate their attacks on a victim.

Botnets may consist of only a few bots or may contain hundreds of individual bots.

Categories of DoS and DDoS Attacks

There are several different categories that individual DoS attacks can fall under.

Volumetric Attacks

A volumetric attack is classified as an attack wherein the targeted network’s resources are purposefully and overwhelmingly consumed by the cyber attacker.

After the bandwidth is consumed by bots, it’s no longer available to genuine users and devices trying to access the network.

These types of attacks happen when a cyber attacker floods the network devices with what’s referred to as ICMP (Internet Control Message Protocol) echo requests. These continue to happen under all of the available bandwidth is consumed.

Fragmentation Attacks

This category of DoS attack consists of any type of attack that forces the compromised network to reassemble network packets that have been maliciously manipulated.

When a fragmentation attack happens, the cyber attacker will send data packets to the network that are manipulated to be impossible for the server to reassemble.

They do this by including more packet header information within each packet than is allowed. The result is headers which are too big to be reassembled in bulk.

TCP-State Exhaustion Attacks

During this type of DoS attack, the hacker will target a firewall or web server, trying to limit how many connections it is able to make.

The purpose of this type of attack is to push a device to its limits with the number of current connections.

Application Layer Attacks

Sometimes referred to as Layer 7 attacks, these attacks target servers or applications and try to use up their resources. It does this by creating as many transactions and processes as possible.

Application layer attacks are very difficult to detect and address and they don’t need a lot of bots to be successful.

Most Common DDoS Attacks

As mentioned earlier, a DDoS attack is more complicated than a DoS attack. This is because DDoS attacks use multiple devices that increase that attack severity. In other words, when you’re attacked by a single computer, it’s almost child’s play compared to being attacked by an entire botnet of hundreds of devices.

DDoS attacks come in a number of different forms, which include:

Ping of Death (POD)

During POD attacks, an attacker will send several pings to an individual computer. The attack contains manipulated packets sent to the network, which contain IP packets larger than the maximum length of a packet.

The illegitimate packets are delivered as fragments. When the victim’s network tries to put the packets back together, the network resources get used up and become unavailable to packets that are legitimate.

The impact is a network that grinds to a halt and is taken completely down.

UDP Flood

This DDoS attack floods the network of the victim with UDP (User Datagram Protocol) packets. It works by flooding the ports of a remote host so that it continually searches for an application that is listening at the port.

After the host discovers that there isn’t an application, it replies back with a packet informing that the destination couldn’t be reached. This process overwhelms the resources of a network, which means that other devices won’t be able to connect.

Ping Flood

These are similar to UDP flood attacks because they use ICMP echo requests or ping packets in order to take a network offline.

An attacker will send these packets very rapidly, without awaiting a reply. This is a direct attempt of using brute force to make a network unreachable. A ping flood attack is particularly harmful because the available bandwidth of the attacked server is consumed by itself while trying to reply with its own ICMP echo reply packets.

This results in a drastic loss of speed across an entire network.

SYN Flood

An SYN flood attack is another attack type where a cyber attacker will use the sequence of the TCP connection to cause the victim’s network to become unavailable.

An attacker will send SYN requests to the network of their victim, which will then respond with what’s known as an SYN-ACK response. Under normal circumstances, the sender would respond and their own ACK response. However, in an SYN flood attack, the attacker doesn’t respond at all.

Every individual request that doesn’t get answered takes up the network resources of the victim until no devices are able to connect.

Slowloris

Slowloris is DDoS attack software developed by Robert Hansen (RSnake) that takes down web servers.

This type of attack happens when a cyber attacker sends over partial HTTP requests without the intent of completing the requests. For the attack to continue going, the software then sends HTTP headers for every request. This keeps the resources of the targeted computer tied up.

This will continue until the targeted server isn’t able to make additional connections. It’s a popular form of attack because an attacker doesn’t need any bandwidth to pull it off.

HTTP Flood

HTTP flood attacks use HTTP GET or POST requests with the intent of launching an attack on a single application or web server. It’s a type of Layer 7 attack but doesn’t utilize spoofed or malformed packets.

An HTTP flood attack doesn’t require a lot of bandwidth, which makes them popular among cyber attackers.

Zero-Day Attacks

This is a type of attack that exploits vulnerabilities that haven’t been discovered yet. It’s really a blanket term for any type of attack that could be faced at a future date.

Zero-day attacks are difficult to guard against because the victim doesn’t know exactly what they should be prepared for.

What are the Differences Between DoS vs DDoS?

Four key differences between DoS vs DDoS attacks:

1. DDoS attacks use multiple connections to knock their victim’s networks offline. DoS attacks use only one connection.
2. It’s more difficult to detect DDoS attacks vs DoS attacks because DDoS attacks stem from many different locations. The victim of the attack can’t locate its origin.
3. DDoS attacks come in much larger volume than DoS attacks. This is because the attacker is able to send massive amounts of traffic to the victim’s network with the many different connections the attacker uses.
4. DDoS attacks are always executed using botnets that the attacker controls. DoS attacks typically come from script use or DoS tools like Low Orbit Ion Cannon.

Why Would Someone Execute a DoS or DDoS Attack?

For either type of cyber attack, there are many different nefarious reasons that an attacker may want to put websites and businesses offline.

Most often, the reasons fall into one or more of these categories:

• Looking for a ransom payout in order to lift the attack
• Malicious competitors that try to take out the competition
• Political disagreements (often called “hacktivism”)
• Making trouble for sport
• Disgruntled current or former employees

No matter the reason, a DDoS attack can do major harm to your website and business if it ever succeeds. This is why, as a responsible WordPress site owner, you need to stay a step ahead of the game.

Preventing DoS and DDoS Attacks On WordPress

DDoS attacks are extremely common among WordPress site owners. And while they aren’t traditional “hacks” in the sense of a hacker taking over your site, they are very devastating brute force attacks that can knock your site completely down.

There are a few important security practices you can put in place on your WordPress site to help it avoid the attention of DDoS attackers.

1. Always Keep Your Site Updated

When you keep your WordPress core, themes, plugins, and other software up-to-date, it helps mitigate the risk of known vulnerabilities being used as weapons against you.

By keeping your site updated, you also reduce the risk of your site becoming a part of a botnet.

2. Use a Powerful Security Plugin

As discussed earlier, some of these attacks will exploit issues such as Slowloris. This and other flaws in security can be shored up by using a powerful WordPress security plugin like iThemes Security Pro.

More on that in a bit.

3. Review Site Logs to Help Identify Problems and Improve Security

WordPress audit logs, along with additional logs, will help you identify any malicious behavior on your site before it becomes a problem.

By using the logs, you’ll be able to identify problems that could be caused by unknown DDoS attacks, such as HTTP error codes. Logs will also give you the opportunity to drill down to the exact source of a cyber attack. There are several different logs that WordPress site owners can put to use to better secure and manage their sites.

4. Harden User Authentication

Even though this is listed as number four, this is just as important as the first three:

Implement strong password policies in WordPress.

This helps ensure that your site users always use strong passwords that are difficult to hack.

And beyond that, it’s absolutely imperative to use two-factor authentication by using a plugin.

This leads to our next point:

WordPress DDoS Protection Plugin

Now that you have a full understanding of the differences between DoS vs DDoS attacks, what’s your next step as a WordPress site owner?

The answer is the iThemes Security Pro plugin. It is the best plugin to secure and protect your WordPress site from DDoS attacks, and all other types of malicious hacks that may threaten your website.

With iThemes Security Pro, you’ll be able to force strong passwords, enable two-factor authentication, and employ local brute force protection while banning users that perpetuate malicious intent on your WordPress site.

If you want to avoid a devastating DDoS attack, the iThemes Security Pro plugin for WordPress is the way to go.

And while nothing is 100% foolproof, the BackupBuddy plugin will be your saving grace if your WordPress site is ever hacked and taken down. With BackupBuddy, you’ll be able to restore your site to perfect working order with only a few clicks.

And that could save a lot of time and energy if the worst should ever happen.

Website Security Is Incredibly Important

Website security definitely needs to be on the top of your priority list. Just take a look at these website security stats to see how urgent the need is to take any active steps to secure your site. Your site is currently at a certain level of risk even while you’re reading this guide.

And even if you’ve taken security steps in the past, it’s important to run updates regularly in order to keep your site protected from the thousands of new threats that are arising every day.

Start by downloading and installing iThemes Security Pro on your WordPress site. It’s your first and best line of defense against hackers that wish to do harm.

Get iThemes Security Pro