Design an application–level protocol. The protocol should serve the issues related to the transactions between an automatic teller machine (ATM) and a bank’s centralized computer. 

 

The important steps need to be considered in design of protocol are as follows:

 

• Verify user’s card and password linked to it.

 

• Query and show the account balance (at BCC).

 

• Money disbursed to the user.

 

• Handle all–too–common case; cover the withdrawal, if there is not enough money.