During the scene where Sandra Bullock is searching for the I.P. address (I think it is when she is in the Cathedral building and setting the fire alarm,) notice that the I.P. address begins with a number higher than 255. I think it was 355 or something like that. This isn't possible, because each part of an I.P. address can't go past on 255, because each part is an 8-bit value (the whole thing is a 32-bit value.)