It's not a standard DDOS relying on brute force. Titanfall is attacked by someone with in-depth knowledge of how the whole distributed backend is organised and

It's not a standard DDOS relying on brute force. Titanfall is attacked by someone with in-depth knowledge of how the whole distributed backend is organised and they're abusing that to keep the infrastructure from working properly. In TF2 there seems to be a whole list of unofficially "banned" streamers, for example, and if one of them tries to play multiplayer some automated script will immediately disconnect all players in the match. That causes a lot of speculation, including suspicions it's run by an ex-employee who worked on those systems internally.