[deanhills]

Have you ever wondered how OVH's anti-ddos mechanism works? I have seen some booter's owner trying to attack me with attacks going as hard as 6 GB/sec on OVH's server but still, the server didn't went down(it lagged a bit and maybe because some packets weren't filtered but it lagged soo less that no one would even doubt if that lagged). 

We're experiencing the same at Gigarocket Manal. We've been using OVH for a while for our VPSs. OVH does it with what they called anti-DdoS protection. Powerful scripts to protect their servers. They've got a write-up about exactly how it works at the link below:
https://www.ovh.com/world/anti-ddos/

In a nut-shell it is the following:

Our anti-DDoS solution is composed of several different internally-built hardware components and technologies. It is present in all OVH points of presence worldwide, so that it can absorb all attacks via the mitigation technique. We are able to mitigate attacks due to a three-step solution, which consists of analyzing traffic, then vacuuming it in order to mitigate it. At OVH, mitigation uses a combination of internal technologies that are collectively called a VAC.

The VAC is a combination of different technologies developed by OVH, and designed to mitigate DDoS attacks. With its unique composition, it can filter incoming traffic so that only legitimate data packets pass through and reach your servers, while illegitimate traffic is blocked. The VAC notably includes a pre-firewall, the Firewall Network and Shield and Armor components.