Abstract: A method for secure user access to the information system through any open communications network consists in encoding of system-allowed user's directives by the disposable command passwords. Then the user obtains the authority to run the commands in the information system once only by means of receipt or purchase of their respective disposable command passwords. The open communications network includes the Internet, telephone lines, wireless, etc. The method offers both hardware and software independence. User can carry out the electronic transactions and control their status in real-time from anywhere without any additional software installation. A system based on the method of disposable command encoding can be applied to electronic payment processing, online banking, money transfers. For disposable password distribution the system uses special password-carrying medium named netnote that the user purchases at a point of sale agent.