C&C series, at least the older pre-Generals ones, work the same way - hashing the full state in each frame and sending it over. When a desync is detected, it du

C&C series, at least the older pre-Generals ones, work the same way - hashing the full state in each frame and sending it over. When a desync is detected, it dumps checksums of the last 256 frames along with current frame's checksums of each object into a log file, these can be compared. The logs also contain brief printouts of most objects on the map, and we actually found an uninitialized field and a few more serious bugs thanks to these printouts. The cheaters also found a small loophole in the hashing, because only specific fields are hashed and not entire objects, one important field was missed that gave cheaters an unfair advantage of seeing the current targets of their opponents' units. It is easy enough to fix when you know about it, fortunately.