DDoS attacks are a type of Denial of Service attacks which is usually caused by many different compromised systems that flood a websites bandwidth or resources. This is often known as a botnet, and can be controlled by malicious hackers to take down big servers or web services. Many large companies often use services such as CloudFlare, which helps prevent against DDoS attacks by filtering all the traffic and only forwarding legitimate users to the site. Many of these services often face extended periods of downtime. This eventually leads to loss of revenue and more business for their competitor.
The tools used to perform these attacks are widely availible on the internet. Only one person running these attacks would only work on smaller websites and individuals, but you would need a lot more computers to take a website like Google down. Some tools are LOIC, HOIC, hping and Slowloris.
GUI for LOIC, an application that sends massive amounts of HTTP/TCP/UDP traffic to a website.
Many hacker groups, such as “Anonymous” use these tools in order to show their impact on the world and take down content and sites they don’t like. Many government sites are subjected to these types of attacks often as well. Companies are often given bad reputations for these outages and it paints a negative image in consumer minds.
As this map shows, on any given day there are attacks on many websites that occur all throughout the world. Services that prevent these attacks often have huge data centers, capable of staying online under huge loads, such as 400 gbps. Big sites without this sort of protection are very vulnerable and they should look into it.
Overall, DDoS attacks are very easy to do on a small scale, but with botnets and more computing power, the attacks can get very strong and do a lot of damage. These attacks may also be used to cover up smaller, more complicated data breaches.