Device-embedded transaction chip

A method of processing a payment transaction at a payment terminal, the method comprising:

• exchanging, by a payment interface of the payment terminal, transaction data with a payment device;
• receiving, at each of a plurality of user input components of the payment terminal, user input data in response to a user input;
• exchanging, by a data interface of the payment terminal, messages via a data communication protocol;
• receiving, at a transaction processing unit of the payment terminal, transaction data from the payment device;
• receiving, at the transaction processing unit, the messages via the data communication protocol;
• receiving, at the transaction processing unit via the data interface, a first command message of a plurality of command message types;
• identifying, by the transaction processing unit, first command message identifying information based on the first command message;
• acquiring, by the transaction processing unit via the payment interface, the transaction data when the first command message identifying information corresponds to a payment request;
• encrypting, by the transaction processing unit, the acquired data based on one or more of the plurality of cryptographic keys;
• identifying, by the transaction processing unit, first response message identifying information based on the first command message and the acquired encrypted data;
• transmitting, by the transaction processing unit via the data interface, a first response message of the response message types;
• receiving, at an application processing unit of the payment terminal and from at least one of the plurality of user input components, a first transaction input;
• generating, by the application processing unit, the first command message based on the first transaction input;
• transmitting, by the application processing unit via the data interface, the first command message to the transaction processing;
• receiving, at the application processing unit via the data interface, the first response message from the transaction processing unit;
• and
• transmitting, by the application processing unit via a IP communication interface, a first transaction processing message to a transaction server, wherein the first transaction processing message includes at least the encrypted acquired data from the first response message.

A plurality of non-transitory computer-readable storage mediums comprising transaction instructions and application instructions stored therein, wherein when the transaction instructions are executed by a transaction processing unit, cause the transaction processing unit to perform operations comprising:

• exchanging, via a payment interface, transaction data with a payment device;
• receiving, from each of a plurality of user input components, user input data in response to a user input;
• exchanging, via a data interface, messages via a data communication protocol;
• receiving transaction data from the payment device;
• receiving the messages via the data communication protocol;
• receiving, via the data interface, a first command message of a plurality of command message types;
• identifying first command message identifying information based on the first command message;
• acquiring the transaction data when the first command message identifying information corresponds to a payment request;
• encrypting the acquired data based on one or more of the plurality of cryptographic keys;
• identifying first response message identifying information based on the first command message and the acquired encrypted data;
• and
• transmitting a first response message of the response message types;
• and
• wherein when the application instructions are executed by an application processing unit, cause the application processing unit to perform operations comprising:
• receiving, from at least one of the plurality of user input components, a first transaction input;
• generating the first command message based on the first transaction input;
• transmitting, via the data interface, the first command message to the transaction processing;
• receiving, via the data interface, the first response message from the transaction processing unit;
• and
• transmitting, via a IP communication interface, a first transaction processing message to a transaction server, wherein the first transaction processing message includes at least the encrypted acquired data from the first response message.