Distributed Denial of Service(DDoS)
An attack that takes a service offline by sending massive amounts of traffic from multiple sources.
What is DDoS Attack?
In one sentence: When thousands of computers attack a site simultaneously and send so much traffic that the site goes down!
Imagine you have a shop. One person comes to buy, no problem. Hundred people come, still okay. But if suddenly 10 thousand people come simultaneously, the shop locks, nobody can get in, you don't sell! DDoS is this — thousands of requests simultaneously, server can't handle, site goes down.
How does it work?
Hacker has a Botnet (thousands of infected computers). Tells them all "send to this site simultaneously!". All send requests simultaneously. Server can't respond, goes down.
Types of DDoS:
Volumetric: High volume traffic. Like UDP Flood.
Protocol: Targets lower layers. Like SYN Flood.
Application Layer: Layer 7 (HTTP). Sends heavy requests. Like HTTP Flood.
Why is it important for security?
Because DDoS can paralyze business. Every minute site is down, financial loss, reputational loss. Some companies pay ransom for attack to stop!