Picture this, you just launched your newest product or feature on your website. The buzz surrounding your launch event is taking off. Incoming traffic is surging and orders are pouring in. Then suddenly, the website becomes unresponsive, and downright unusable. Your IT team narrows down the cause to a massive surge of incoming traffic from all over the world. There seems to be no common thread linking the traffic other than it targeting your application. Ten minutes goes by, twenty, thirty, an hour, your site has effectively disappeared from the internet. This is a DDoS attack, and it has ruined your new launch event.
What can you do to avoid being crippled by this malicious traffic in the future? Don’t panic, we got you covered!
- What Is A DDoS Attack?
- How Do DDoS Attacks Work?
- 7 Ways To Mitigate Incoming DDoS Attacks
Before we can mitigate, or otherwise counteract incoming DDoS attacks we should first understand what they are and how they work.
What Is A DDoS Attack?
A distributed denial-of-service (DDoS) attack is a cyber-attack that overwhelms a target with a flood of traffic from multiple sources. This causes the target to become unavailable to legitimate users, or even completely crashes the website/application.
DDoS attacks can be launched against any type of online target, including websites, web applications, and even entire networks. They are often used by criminals to extort money from victims, or to disrupt the operations of businesses or government agencies.
How Do DDoS Attacks Work?
There are two general types of DDoS attacks: volumetric and application-layer attacks. They vary in their approach but ultimately serve the same end-goal, disruption, i.e. denial-of-service.
What Is A Volumetric DDoS Attack?
Volumetric attacks flood the target with a large amount of traffic. This can be done by sending a large number of HTTP or other service requests, or by using a botnet to send UDP or ICMP packets.
What Is An Application-layer DDoS Attacks?
The Application-layer attack can be done by sending malicious requests that exploit vulnerabilities in the website/application, or by flooding the application with requests that it does not normally handle.
7 Ways To Mitigate Incoming DDoS Attacks
Now that we know what we are dealing with, it’s time for the tricky part. Lets get into a number of methods to mitigate DDoS attacks. Some of the most common methods include:
#1. DDoS-protected Hosting Provider
Many hosting providers offer DDoS protection as a service. This can help to protect your website or application from even the most sophisticated DDoS attacks. These solutions usually require little to none preparation on your part as the hosting provider can detect and switch-on mitigation strategies automatically.
#2. Hardware Firewalls
A firewall can help to block malicious traffic from reaching your servers. However, we need more than just your typical software based firewall running on your servers. Software firewalls can only do so much and are easily overwhelmed by small or mid-tier DDoS attacks. The solution to this problem is deploying an edge-network hardware-based firewall device. These specialized network devices sit in front of your server(s) and can effectively curtail large volumes of incoming traffic. Preventing it from ever reaching and crippling the application servers.
#3. Load Balancers
A load balancer is another special edge-network device that distributes traffic across multiple backend servers. On its own, a load balancer is not a DDoS mitigation tool. However, since its entire purpose is to efficiently divide traffic up between multiple application servers, this inherently helps to prevent a single server from being overwhelmed.
#4. Botnet Mitigation Service
Botnet attacks are a type of DDoS attack that uses a network of infected computers, called a botnet, to flood a target with traffic. Botnet mitigation services are cloud-based services that protects websites/applications from botnet attacks. Some examples are: Cloudflare, Imperva, or Sucuri.
#5. Keep Software Updated
Since Application-layer DDoS attacks rely on bug exploitation in common software, it is pivotal to keep any software backing your application updated as frequently as possible. This lowers the overall surface area on your site that is susceptible to these styles of attacks. You can think of this like finding and plugging holes in a boat.
#6. Content Delivery Network (CDN)
Like a load balancer a CDN is not a DDoS mitigation tool. However, a CDN reduces the impact of any ongoing DDoS attack as it redistributes incoming traffic to localized servers in the originating geographical region. Spreading out requests significantly reduces the footprint of your site, making it more resilient to large surges in traffic.
#7. Change DNS of Affected Domains
Another approach for effective DDoS mitigation is changing the DNS records for domains that are not critical to the uptime of your application. Since the first stages of any network request is to perform a DNS lookup, changing or removing the IP address associated with effected domains eliminates the traffic from hitting said domain. If you are hosting multiple domains on a single server, this becomes an effective solution for maintaining uptime on those domains that are not direct targets of incoming DDoS traffic.
DDoS attacks are a serious threat to your online businesses and/or organizations. However, there are a number of strategies available which reduce your susceptibility to these terrors of the online world.
Jason Potter is a Senior Linux Systems Administrator & Technical Writer with more than 20 years experience providing technical support to customers and has a passion for writing competent and thorough technical documentation at all skill levels.