Name of ISP : Orange
Country of Residence : France
When does the problem occur : Always

Concerning this matter, there is a long history in France between some ISP such as Orange and Free with the "transit provider" (fournisseur de transit) named Cogent. So i m pretty sure that when we send data to the server and when the server sends us some data then if it goes through the Cogent network then we ll have latency spikes.

Yesterday i tried to complet the fight vs Titan with some other players from Europe (1 player from Finland, Spain, UK and me from France). And it was a HUGE pain in the a** to complet this fight because even if we were outside of some AOE attacks, the server acted as if we were still in it from time to time. And when your screen freezes for 0.2-0.5s during the fight or when the server doesn't see you being outside of an AOE it ends badly... It was a really frustrating fight because the difficulty wasn't coming from the boss itself but from the latency.

And as an European player i m really disapointed by Square-Enix as far as i ve read that European servers where located in Canada ! Do you guys know your geaography ? Canada is VERY far away from Europe. How could it be ok to have EU servers located in North America if you want to have a low latency ? Anyway, if such a matter still occurs for the high lvl content then i already know that me and people from my guild won't stay as far as it won't be possible to play and fight bosses without being killed by the latency.