Hierarchy in an ATM System
- Checking of the pin entered is done.
- If the pin is wrong,user is asked to re-enter.
- Else he can view his balance or
- Withdraw the required amount of money.
- Control is then passed to Auto-teller machine.
- Hierarchy re-inforces the concept of modularity.
- It helps in delegation of the work of designers.
- It is easier to design a complex system.
Hierarchy in an ATM System
Processing
User Interface
Withdrawl
- Money is given along with the receipt
- Inserts the card
- Enters the pin
- Checking of the pin
- Processing the request
of customer
Example 2:
Processing Sub-system
Advantages of using Hierarchy: