Ordering gives you ... ordering. And nothing more. Process 1 receives: 3:00 [1] "P1 is leader" 3:01 [2] "P2 is leader" Process 2 receives: 3:00 [1] "P1 is lea

Ordering gives you ... ordering. And nothing more. Process 1 receives: 3:00 [1] "P1 is leader" 3:01 [2] "P2 is leader" Process 2 receives: 3:00 [1] "P1 is leader" 4:00 [2] "P2 is leader" This is perfectly valid Atomic Broadcast. Order is maintained. However from 3:01 to 4:00PM you have 2 leaders (or 2 processes holding the lock). Don't use ABCast to do locking / leader election for your "user-space" application!