HTTP Amplification is a term often used in the context of cyber attacks and internet security. It refers to a type of Distributed Denial of Service (DDoS) attack where the attacker uses HTTP requests to redirect excessive traffic to a server or website.

Essentially, the attacker exploits a variety of HTTP requests to overwhelm the server, making it inaccessible to legitimate users. This is often done by exploiting vulnerabilities in web server configurations or utilizing botnets to send a large number of requests.

The term "Amplification" refers to how the attacker "amplifies" the traffic by sending small requests, which are then responded to by the server in much larger replies. This can cause the server to expend a significant amount of resources processing these requests, rendering it unreachable for legitimate users.

To protect against HTTP Amplification attacks, web servers can be configured to limit requests or implement filters to identify and block suspicious requests. Additionally, Content Delivery Networks (CDNs) and DDoS protection services can be employed to monitor traffic and mitigate attacks before they reach the server.