DoS vs DDoS Attacks
A Denial of Service or DoS attack is when someone crafts a request, tailored to programs on the target service, with the aim of bringing it down. This makes it similar to a real hack.
The request originates from a single machine.
A DDoS attack on the other hand is a large number of often identical requests, from hundreds of different machines with the aim of flooding a service so legitimate users cannot access it.
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