The company TelcoServ sells the product Walk & Talk, a prepaid monthly plan including voice calls for 20ยข/minute. Customers can choose to buy an add-on of 60 minutes for 1$ during one month. To meet this service, TelcoServ uses the allowance logic in their plan.
The allowance logic contains:
An allowance component (Event-Based Trigger component) to decrement the counter Free_minutes (the Event-Based Trigger is activated when receiving an event related to the allowance and sent by an Allowance Event Sender Operator component)
The persistent counter Free_minutes set to the initial value of 60
In the allowance tree:
The first branch checks if there is enough remaining free minutes
The second branch allows the whole duration
The third branch allows part of the duration
For more information on logic components, click Components on the Help menu of the main window.