Question

Design and describe an application-level protocol to be used between an automatic teller machine (ATM) and bank centralized computer. Your protocol should allow a user’s card and password to be verified, the account balance (which is maintained at the centralized computer) to be queried, and account withdrawal to be made (that is, money disbursed to the user). Your protocol entities should be able handle the all-too-common case in which there is no enough money in the account to cover the withdrawal. Specify your protocol by listing the messages exchanged and the action taken by the ATM or the bank’s centralized computer on transmission and receipt of messages. Sketch the operation of your protocol for the case of a simple withdrawal with no errors, using a diagram similar to that in Figure 1.2 of the textbook.

Answer 1