Q$3.$ We use the following modes for financial transactions now$-$a$-$days.

ATM

Web$-$based interface

POS machine

Mobile Applications $($Like BHIM, Google Pay, etc.$)$

To do a transaction through any mode mentioned above, a user must provide sensitive information such as PIN Code, Card number, expiry date, CVV$,$ etc. The disclosure of this information to other than the intended user can cause financial loss. Therefore, design a lightweight solution$/$protocol to enable secure transactions through the modes mentioned above. The protocol must do mutual authentication of communication parties and provide confidentiality and integrity of sensitive information.

$2+2+2$