TCP/IP Protocol Suite 4th Edition by Behrouz Forouzan

Exercise 3

Show the FSM for an imaginary machine with three states: state A (starting state), state B, and state C; and four events: events 1, 2, 3, and 4. The following specify the behavior of the machine:
a. When in state A, two events may occur: event 1 and event 2. If event 1 occurs, the machine performs action 1 and moves to state B. If event 2 occurs, the machine moves to state C (no action).
b. When in state B, two events may occur: event 3 and event 4. If event 3 occurs, the machine performs action 2, but remains in state B. If event 4 occurs, the machine just moves to state C.
c. When in state C, the machine remains in this state forever.