Payment system

A method for making a payment, the method comprising:

• creating a trust card in a server system, and
• transmitting data of said trust card to a terminal, to be used for performing a payment transaction,
• forming a secret for a payment application in the server system, and
• making said secret of the payment application available for use by the terminal for activating said trust card for performing the payment transaction, wherein the secret of the payment application has a validity term, during which it can be used in an authorized manner for activating the trust card.

A device comprising at least one processor, a memory and a computer program code in said memory, the computer program code being configured, when run in said at least one processor, to cause the device:

• to receive a secret of a payment application from an operator's server system to the terminal,
• to activate a trust card in said user's terminal by utilizing said secret of the payment application,
• to receive payment data from a point-of-sale terminal to a user's terminal,
• to transmit said payment data to the server system to be verified,
• to receive a second secret, formed by the server if said verification produces an acceptable result, said second secret being configured to be used for verifying the payment transaction, and
• to transmit data of the trust card and said second secret from said user's terminal to said point-of-sale terminal for performing said payment transaction.

A server system comprising at least one processor, a memory and a computer program code in said memory, the computer program code being configured, when run in said at least one processor, to make the system:

• create a trust card in the server system, and
• transmit data of said trust card to a terminal, to be used for performing a payment transaction,
• form a secret for the payment application in the server system, and
• make said secret of the payment application available for use by the terminal for activating said trust card for performing the payment transaction wherein the secret of the payment application has a validity term, during which it can be used in an authorized manner for activating the trust card.