Suppose you have a virtual shopping outlet. While everything appears to be in place in terms of orders and clients, suddenly there is a disruption in the online store’s functionality due to poor connectivity. In a matter of minutes, customers are unable to log on to your website. One of the concerns can be related to a server failure or a sudden burst of traffic from legitimate customers. However, this disruption might well be a DDoS (Distributed Denial-of-Service) attack.
When it comes to web assaults to paralyze any particular website, the term DDoS attack is used to define an attempt to disrupt a service by means of overwhelming the intended site, server, application, or network. The difference between DDoS and regular DoS attacks is that the former involves many networks that attempt to disrupt the service of the attacked entity.
The use of DDoS can cause trouble for businesses of all sizes. Anyone working in Cybersecurity should be aware of this fact.
What is a DDoS Attack?
So what are DDoS attacks? The term “Distributed Denial-of-Service Attack” refers to a type of cyber attack aimed at stalling access to a specific server, service, network, or program thanks to an abundance of requests on the part of malicious users.
The term “distributed” is the key aspect here.
Rather than attacking from only one machine, such an attack can be initiated from numerous virtual devices, which can be wrongfully controlled. Such devices consist of computers, servers, routers, and other IoT devices. A large number of wrongfully controlled devices used for interference is called a botnet.
The aim of the attack is not to gather information but to make the service inaccessible.
Still, at times, such attacks can be a part of a larger plan along with other attacks, allowing criminals to carry out their plans undetected.
What Is the Process Behind a DDoS Attack?
DDoS attack is basically completed in three major stages.
Building or getting hold of Botnets
Intruders can take advantage of devices connected to the internet and use them to perform the attack. Thus, a massive network of those devices, known as a botnet, can be created.
The owners of hacked devices may not be aware that their devices are already under the control of the intruder.
IoT devices often play a crucial role in this process because they usually have poor defenses or outdated software. The attacker may also use an existing botnet.
Conducting the Attack
The next step is to direct the traffic towards the target. After getting hold of several devices, the attacker starts sending requests and packets to the target. The target could be a website, API, application, server, network device, etc.
What is the Difference Between DoS and DDoS?
Though DoS and DDoS are related, they refer to different attack structures. But what is DoS attack? A DoS attack usually utilizes a single source or connection to disrupt a service. A DDoS attack employs many sources of attack traffic, often distributed across many compromised devices.
The distributed nature of DDoS attacks can make it hard to filter since traffic comes from different locations and devices instead of a single obvious source.
DoS | DDoS |
Generally emerges from one source | Uses many distributed sources |
Smaller attack infrastructure may be enough | Often depends on several traffic sources |
Source can be comparatively easier to find | Traffic can emerge from multiple locations |
Can overwhelm a target | Can create large or distributed traffic volumes |
The exact methods could vary and not every DDoS attack relies on a conventional botnet.
Common Types of DDoS Attacks
DDoS attacks have the potential to be launched against various levels and aspects of an online service. Volumetric DDoS attacks refer to those attacks whose aim is to utilize all available bandwidth associated with the target. In a volumetric DDoS attack, the attacker produces huge amounts of traffic in order to create some kind of congestion in the network. When the traffic amount exceeds the capacity of the network, normal users will be unable to access the online service.
Protocol DDoS attacks refer to DDoS attacks based on exploiting vulnerabilities of particular protocols and intermediaries involved in the process. Protocol DDoS attacks draw resources from various devices, including but not limited to firewalls, load balancers, and other network devices.
Cyber assaults on the application layer concentrate on attacking applications rather than seeking to use high network bandwidth.
For instance, the attackers might issue numerous requests that would require lots of computer processing power from a site or server.
As such, it is not necessary for a given attack to have exceptionally high bandwidth to create havoc. The few requests that consume lots of resources can be sufficient.
Cloudflare has a separate classification for application-layer attacks because such attacks target the place where applications generate and deliver responses to clients.
What Are the Indicators of a DDoS Attack?
Just because a website is slow does not mean that it is a victim of DDoS.
Heavy legitimate traffic, software bugs, hardware issues, connectivity trouble, and other problems can also present similar indicators.
That said, there are legitimate signs that perhaps can lead to a deeper investigation. Such indicators might be the appearance of unexpected spikes in traffic. Organizations might notice abnormal traffic patterns directed at some addresses or an unusual amount of traffic coming from unexpected geographical locations. Other symptoms are increased loading times, increased utilization of resources, a high number of failed connections, and inability to access some services.
According to MDN, slow network performance and inaccessible websites can characterize a denial-of-service attack as well.
In any case, it is always advisable to analyze traffic patterns rather than to assume that every downtime is a DDoS attack.
What Are the Implications of a DDoS Attack?
The most immediate effect is disruption of services.
For an e-commerce business, this could mean the inability of users to go through catalogues or to make purchases. For a SaaS business, users may be cut off from important software solutions. For a banking institution, service disruption may affect clients and internal operations.
The consequences can be greater than just downtime.
Companies may suffer from lost profits, client irritation, operational problems, higher infrastructure costs, and reputation damage.
The severity of the attack depends on the target, scale, time of the attack, security measures, and the company's ability to mitigate threats.
What Methods Can Companies Use to Prevent DDoS Attacks?
A business cannot rely on any single security technique to be protected from DDoS attacks. It is necessary to create several protective barriers to ensure different aspects of defense.
Use Traffic Monitoring
Ongoing traffic analysis gives organizations the chance to define their regular traffic behaviour. If something goes wrong, security managers can analyse what caused the problem. Monitoring enables companies to analyze traffic volume, rate of requests, locations of the users, application endpoints, rate of errors, and consumption of infrastructure resources.
Use Rate Limiting
This means limiting the number of requests a user, an IP address or any other source can send during some period of time that can eliminate the influence of some types of large incoming traffic.
Cloudflare emphasizes that this is one of the DDoS security methods. However, one has to understand that the limits have to be set carefully. Too strict limits might stop real customers from accessing the page.
Employ a Web App Firewall
The Web Application Firewall (WAF) tends to evaluate web traffic and apply rules designed to block suspicious requests.
WAFs are particularly effective regarding application-layer protection as they evaluate aspects of the HTTP requests instead of just the network traffic.
It is essential to revise the WAF rules from time to time because legitimate applications also change over time.
Understanding DDoS Protection Mechanism
DDoS protection is primarily about detecting malicious or abnormal traffic and blocking it from reaching the targeted application or system.
This protection could take place depending on how the DDoS solution is designed; some may take place at the network’s edge, while others could happen at the origin site.
Traffic could initially pass through a distributed security solution where suspicious traffic patterns are filtered out, while legitimate requests are forwarded to the origin server or infrastructure.
The other controls may entail rate limiting, the use of WAF rules, traffic filtering, load balancing, caching, and automated detection.
The goal is not just to block “large amounts of traffic”; there are many legitimate traffic events that produce traffic spikes, such as product launches, ticket sales, viral content, and major sales.
This is why effective mitigation differs from blocking unwanted traffic.
DDoS Shielding in Cloud Settings
The field of computing has led to a complete change in the approach of companies towards the DDoS resilience concept.
Cloud platforms afford scalable infrastructures and integrated security services. However, merely shifting an application to the cloud can not guarantee protection from DDoS attacks.
It is still necessary for companies to implement proper network architecture, filtering, application security, monitoring, access control and incident response activities.
The applications operating in the cloud have a number of dependencies such as third-party services, APIs, authentication systems and databases, and without protection of these components it is impossible to ensure complete protection of the application itself.
Effects of DDoS Attacks on Small Enterprises
Small enterprises might be more worried about DDoS attacks as they do not have sufficient information technology resources in comparison with larger companies. However, it does not mean that they need to develop a massive security infrastructure.
DDoS protection and security services can be found in hosting providers, such as managed DDoS protection services, various cloud-based security suppliers (including CDN), solutions for web application firewalls, monitoring programs, and adequate infrastructure architectures.
The best solution will depend on the size of the organization’s traffic, the architecture of its applications, the needs of the business, and the risk level.
Final Thoughts
DDoS attacks can be classified as attacks targeting availability aspects. When DDoS attacks occur, attackers attempt to deny genuine users access to a service by overloading the resources necessary for providing such service.
To fight such attacks, businesses must combine various cybersecurity technologies and approaches. More specifically, they must be able to recognize normal traffic, utilize multiple safety measures, implement reasonable traffic limitations, ensure application protection, deploy distributed infrastructure, and elaborate a response strategy in advance.
Most importantly, organizations must be proactive. If DDoS attacks successfully intimidate a targeted organization, it will not help.
Frequently Asked Questions
What is a DDoS attack?
DDoS attack is an attack on a website, application, server, or network that tries to influence it by sending malicious traffic or requests coming from many sources.
What is DDoS?
DDoS is an abbreviation for the term Distributed Denial-of-Service.
How does a DDoS attack happen?
The attackers send requests from several sources to the target.
What is a botnet in case of a DDoS attack?
A botnet is a group of compromised or controlled devices that are used to launch an attack.
What are the types of DDoS attacks?
The main types of attacks are the following: volumetric attacks, protocol attacks, and application-layer attacks.