An automated ticket machine sells rail tickets. Users select their destination and input a credit card and a personal identification number. The rail ticket is issued and their credit card account charged. When the user presses the start button, a menu display of potential destinations is activated, along with a message to the user to select a destination and the type of ticket required. Once a destination has been selected, the ticket price is displayed, and customers are asked to input their credit card. Its validity is checked, and the user is then asked to input his or her personal identifier $($PIN$).$ When the credit transaction has been validated, the ticket is issued.

Write a set of non$-$functional requirements for the ticket$-$issuing system, setting out its expected reliability and response time.