Show how finite state machine model helps in designing a switching system and give a typical example.

Switching system fundamentally belongs to the class of finite state machines (FSM) that are asynchronous in character and follows a sequential logic for its operation. They can be modeled using a memory part and a combinational part as shown in figure. In FSM, the status of the output circuits not particularly depends on the inputs but also on the current state of the machine. Asynchronous sequential operation provides rise to several problems due to transient variations which may occur in the logic circuits and memory components. Clocked synchronous operation demonstrated in figure overcome such problems

FIG - FSM Model.