Technology has become a fundamental cornerstone of modern business, with organizations investing millions to secure their infrastructure against cyberthreats. Any attack on availability can ruin reputations and cause massive revenue losses in this interconnected world. Two of the most critical threats to availability are Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks. In this article, we will discuss the fundamental differences between these two attacks and the mitigation strategies that you can implement to protect your business against them.
What Are DoS and DDoS Attacks?
Denial of Service (DoS) Attacks
A DoS attack is a malicious attempt by a bad actor to disrupt the availability of its target, be it a server, network, or application. The attacker floods the victim with illegitimate requests, making it unable to service legitimate ones from valid users. Attackers typically use a system or a group of systems to send these malicious data packets. Some standard techniques involve sending a flood of data packets or transmitting malformed data packets that can cause a system to become choked to its total capacity. The infamous Ping of Death is one classic example of a DoS attack.
Distributed Denial of Service (DDoS) Attacks
A DDoS attack functions similarly to a DoS, but on a vastly larger scale. As defenses have improved, simple DoS attacks are no longer effective against many systems, leading to a rise in DDoS attacks. As the name implies, instead of relying on a single system, the attacker uses a vast array of devices (often called a botnet) to generate massive amounts of traffic. The sheer volume of this attack can overwhelm even the most fortified of networks. Devices distributed across the globe, such as IoT, laptops, and smartphones, are often compromised by attackers beforehand so they will be more susceptible to the attack. This makes DDoS threats highly difficult to defend against compared to traditional DoS attacks. These attacks have increased in volume over the years and are wielded by both cybercriminals and nation-states as a cyber weapon.
Understanding the Key Differences
DoS and DDoS attacks differ from each other in a several key ways:
-
Volume: As mentioned above, the major difference lies in the number of devices used to carry out the attack. While a DoS attack relies on a relatively smaller and limited number of devices, DDoS attacks utilize a botnet of many compromised devices spread across various locations, making it difficult to block and defend against.
-
Complexity: DoS attacks are trivial to execute with commonly available tools and scripts, whereas DDoS attacks require planning and coordination. Given the resources and effort required, the latter is mainly carried out by nation-states or cybercriminal groups.
-
Impact: DoS attacks can be considered a nuisance due to the limited amount of damage they cause, typically restricted to a single system or network. On the other hand, DDoS attacks can be devastating, causing large periods of outage for organizations and governments across the globe. They can restrict access to essential systems, important public services, and critical infrastructure. The long-term implications of DDoS attacks, such as reputational and financial damage, can be severe and take years to rebuild.
-
Mitigation: Given their limited scale, traditional security controls such as blocking IP addresses and rate limiting are generally effective against DoS attacks. DDoS attacks, on the other hand, require a layered strategy due to their multiple sources. Organizations may need to rely on specialized third-party services and controls like traffic analysis, anomaly detection, etc. to deal with the scale of these threats.
Detecting DoS and DDoS Attacks
The first step to protecting against either attack is understanding the common indicators. The earlier you notice something is wrong, the more the damage can be prevented. Some notable signs of these attacks are:
-
Slow Performance: One of the most common signs of DoS or DDoS attacks is a slowdown in system or network performance. Users may suddenly be unable to access systems or carry out normal operations. Websites may abruptly start slowing down, or services may stop responding. This typically occurs as the server or network is overwhelmed with the traffic generated by the attack.
-
Threat Intelligence Results: Threat intelligence services may alert organizations that house critical systems or infrastructure, warning them of incoming DDoS attack chatter. These agencies often monitor underground black markets and forums on the Dark Web, which can give clues about upcoming attacks.
-
Emails: DoS or DDoS attacks are often preceded by threatening emails informing organizations of incoming attacks unless a payment is made. While such emails may be fake or harmless, cybersecurity teams need an open channel to be informed about such messages. This can help them proactively increase the security posture before an attack begins.
-
Security Monitoring: Organizations that monitor network patterns may be able to detect signs of malicious traffic such as spikes that indicate a DoS or DDoS attack. Knowing what “normal” traffic looks like is essential, so any deviation from this baseline can be flagged as a potential attack. Sudden increases in requests from IP addresses or a particular region can be identified and blocked before a major attack occurs.
Implementing Effective Mitigation Strategies
As discussed earlier, it is essential to have a layered mitigation strategy to protect against DoS or DDoS attacks. Some of the most useful controls that can be implemented are:
IP Blacklisting
One of the most straightforward ways to prevent attacks is to block malicious IP addresses from sending traffic. Administrators can simply update firewall rules or security tools to deny access from specific IP addresses in case of an attack. However, while this may work against DoS attacks, it cannot mitigate DDoS attacks due to the sheer number of devices.
Rate Limiting
This technique limits the number of requests that may originate from a particular network within a specific time frame. This stops a specific source from overwhelming a network with massive amounts of data and ensures that no one source can flood the network. With DoS attacks, rate limiting a particular IP address may be sufficient, but preventing DDoS attacks may require rate limiting across different parts of the network to deal with the scale of the attack.
Load Balancing
Load balancing is an effective technique for distributing incoming network traffic across various servers. This can effectively handle high volumes of traffic, as it prevents a single server or network from being overwhelmed. Architecting networks for load balancing improves their resilience and adds other security layers against attacks that target availability, such as DoS and DDoS attacks. Using cloud-based services often helps load balance between different regions and data centers, ensuring no location is a single point of failure. The scalability and distributed nature of the cloud make it an ideal choice for implementing such strategies.
Specialized Anti-DDoS Services
One of the best ways to mitigate large-scale DDoS attacks is to rely on providers that have dedicated expertise in dealing with such attacks. These services rely on a global network to absorb the impact of DDoS attacks before they can reach a company’s network. This provides organizations with real-time threat detection and mitigation without re-architecting their networks. These services can often quickly collaborate with government agencies and Internet Service Providers (IPSs) in the event of an attack to help reroute traffic or gain access to additional bandwidth.
Security Hardening
Patching and ensuring systems are appropriately hardened is crucial against DoS or DDoS attacks. Vulnerabilities in these systems may be exploited to either compromise their availability or use them as part of a botnet to attack other networks. Staying up to date on patching will reduce the network’s attack surface and improves its overall security posture.
Incident Response Plans
It can be quite easy to become overwhelmed in the event of a DoS or DDoS attack. Having a formalized and tested plan for incident response is essential for knowing that to do during and after an attack. This enables organizations to identify the actions that must take place, such as initiating DDoS mitigation services, blocking traffic, engaging with Internet Service Providers (ISPs), etc. A well-made incident response plan ensures that businesses respond to attacks in a coordinated and organized manner.
AI and Machine Learning
AI-based traffic analysis is an emerging trend that can be quite effective in detecting abnormal network traffic. The amount of network traffic that is generated normally can be overwhelming for traditional security solutions, so leveraging AI can be an effective method to improve detection. The power of machine learning allows organizations to quickly baseline what constitutes normal behavior, making it easier to identify if an attack is taking place.
Conclusion
Mitigating DoS and DDoS attacks requires a layered approach to security. It is important to understand the key differences between these attacks and implement controls that effectively guard against them. While both attacks can harm organizations, their complexity, scale, and impact on networks differ greatly standard controls may mitigate DoS attacks, but DDoS attacks require specialized services due to their advanced nature. Once organizations understand these differences, it becomes easier to implement focused security strategies and protect against these dangerous cyberattacks.
Thank you for trusting us to help with your cybersecurity needs. Contact us any time – we’re always happy to help.
Adam
