Distributing payment keys among multiple discrete devices in a point of sale system

A point of sale system comprising:

• a first discrete device with a first means for receiving payment information;
• a second discrete device with a second means for receiving payment information;
• a wire communicatively connecting the first discrete device to the second discrete device;
• a secure connection between the first discrete device and the second discrete device over the wire using a protocol;
• a second secure memory on the second discrete device that stores:
• (i) a public key certificate and a corresponding private key;
• and (ii) a copy of a payment key delivered from the first discrete device over the wire via the secure connection;
• and
• a first secure memory on the first discrete device that stores:
• (i) a public key from the public key certificate after the public key certificate is verified;
• and (ii) the payment key;
• wherein the first secure memory and the second secure memory store instructions to conduct a handshake for the protocol using the public key from the public key certificate and the corresponding private key.

A method comprising:

• storing a payment key on a first discrete device for a point of sale system;
• storing a public key certificate and a corresponding private key on a second discrete device for the point of sale system;
• communicatively connecting the first discrete device with the second discrete device using a wire;
• transmitting the public key certificate from the second discrete device to the first discrete device using the wire;
• verifying the public key certificate on the first discrete device;
• and
• finalizing a secure connection between the first discrete device and the second discrete device over the wire using a transport layer secure (TLS) protocol after the public key certificate is verified.