Electronic transaction security system and method

1. A method for providing access to a first account maintained by an institution, wherein the first account has a predetermined expiration and is associated by the institution with an account number, an identifier that is unique to the first account among accounts that the institution maintains that are accessible at a computer by users remote from the computer via a wide area network, and authentication data that the institution requires to be submitted to the institution as a condition to grant access to the first account, the method comprising the steps of:

generating by a mobile device a login credential, that is different from the account number according to a predetermined algorithm so that the login credential has a same number of digits as the account number and includes a first set of digits corresponding to the identifier, a second set of digits corresponding to the authentication data, and a third set of digits corresponding to data identifying a time that is earlier than the expiration of the first account;

transmitting the login credential from the mobile device to the computer via the wide area network; and

in response to confirmation by the institution that the login credential received by the institution from the transmitting step corresponds to the first account, interacting with the first account from the mobile device via the wide area network and the computer.

2. The method as in claim 1 , wherein the time data corresponds to an expiration date of the login credential.

3. The method as in claim 1 , wherein the time data corresponds to a time at which the login credential is generated.

4. The method as in claim 1 , wherein the computer is a server.

5. The method as in claim 1 , wherein the authentication data is a private identification number defined by the institution.

6. The method as in claim 1 , wherein the authentication data is a private identification number defined by the user.