The Ubisoft Forums
have posts from customers who were unable to play games protected by Ubisoft's online DRM yesterday because the DRM servers were offline. Needless to say most of the posts express severe unhappiness at being unable to play and express anger over a DRM scheme that locks paying customers out of their own game. This Ubisoft tweet
explains: "Apologies to anyone who couldn’t play ACII or SH5 yesterday. Servers were attacked which limited service from 2:30pm to 9pm Paris time," and this one
follows up: "95% of players were not affected, but a small group of players attempting to open a game session did receive denial of service errors."