Financial transmission system

A device for performing financial transactions in conjunction with a telephone over a communications link in a communications network with a computer at a remote location, using a financial card having an account code, the device comprising:

• control means for controlling operation of the device;
• reader means for determining the account code of the financial card;
• DTMF transmitter means, coupled to the control means for receiving the account code of the financial card from the control means and for transmitting the account code over the communications link of the communications network as DTMF signals;
• receiver means for receiving information sent by the remote computer via the communications link and for providing the information to the control means;
• a communications connector adapted to connect to the communications network and the telephone so that voice communications can be performed by the telephone over the communications link and so that the device can transmit and receive data to and from the computer at the remote location, respectively, over the communications link used by the telephone to perform voice communications;
• and
• a muting means connected to the control means, the control means selectively activating the muting means for muting the DTMF signals generated by the DTMF transmitter to reduce the sound level of the DTMF signals in an earphone of the telephone.

A device for performing financial transactions in conjunction with a telephone over a communications link in a communications network with a computer at a remote location, using a financial card having an account code, the device comprising:

• control means for controlling operation of the device;
• reader means for determining the account code of the financial card;
• means for transmitting the account code over the communications link of the communications network;
• receiver means for receiving information sent by the remote computer via the communications link and for providing the information to the control means;
• a communications connector adapted to connect to the communications network and the telephone so that voice communications can be performed by the telephone over the communications link and so that the device can transmit and receive data to and from the computer at the remote location, respectively, over the communications link used by the telephone to perform voice communications;
• and
• a power supply connected to the telephone line for supplying power to the device solely by the power received from the telephone line, the power supply further being connected to the reader means, the transmitting means, the receiver means, and the control means to supply power thereto.

A device for performing financial transactions in conjunction with a telephone over a communications link in a communications network with a computer at a remote location, using a financial card having an account code comprised of a detectable portion and a nondetectable secret portion, the device comprising:

• control means for controlling operation of the device;
• reader means for determining the detectable code portion of the financial card;
• an entering means for manually entering the secret code portion;
• security means for encoding at least the secret code portion of the account code to prevent interception and deciphering of the secret code portion;
• means for transmitting the detectable code portion and the encoded secret code portion over the communications link of the communications network;
• receiver means for receiving information sent by the computer via the communications link and for providing the information to the control means;
• a communications connector adapted to connect to the communications network and the telephone so that voice communications can be performed by the telephone over the communications link and so that the device can transmit and receive data to and from the computer at the remote location, respectively, over the communications link used by the telephone to perform voice communications;
• and
• a power supply connecting to the communications network to provide power to the device solely from the power of communications network.

In a financial network comprising a device at a user location for performing financial transactions in conjunction with a telephone over a communications network with a computer at an acquirer location (acquirer computer) and a computer at a device issuer location (device issuer computer), the device being adapted to transmit a secret account code, associated with a financial account of a financial card, over the communications network, a method for securely transmitting the secret account code over the communications network to allow a financial transaction to be conducted with the acquirer computer, the method comprising:

• programming a secret master key into the device;
• programming a nonsecret identity offset into the device;
• maintaining a lookup table associating the master key to the nonsecret identity offset at the device issuer location;
• generating a working key for encrypting data between the acquirer computer and the device;
• and
• using the identity offset, the master key and the lookup table to make the working key common between the acquirer and the device.

In a financial network comprising a device at a user location for performing financial transactions over a communications network with a computer at an acquirer location (acquirer computer) and a computer at a device issuer location (device issuer computer), the device being adapted to transmit a secret account code, associated with a financial account of a financial card, over the communications network, a method for securely transmitting the secret account code over the communications network to allow a financial transaction to be conducted with the acquirer computer, the method comprising:

• the device transmitting a device issuer
• identifier (ID) associated with the device for designating the issuer of the device, and an identity offset associated with a master key common to the device and device issuer computer to the acquirer computer in unencrypted form;
• the acquirer computer, in response to receiving the identity offset and the device issuer ID, generating a random working key;
• the acquirer computer transmitting the working key and the identity offset to the device issuer computer designated by the device issuer ID in encrypted form under a predetermined encryption key common to the acquirer computer and the device issuer computer;
• the device issuer computer unencrypting the encrypted identity offset and working key under the common encryption key;
• the device issuer computer determining the master key associated with the identify offset;
• the device issuer computer transmitting the working key in encrypted form under the master key to the acquirer computer;
• the acquirer computer transmitting the working key encrypted under the master key in unencrypted form to the device;
• the device unencrypting the working key encrypted under the master key by the device issuer computer with the master key which is common between the device and the device issuer computer, whereby the working key is common to the device and the acquirer computer;
• and
• the device, after receiving the secret account code of the financial card, transmitting the secret account code of the financial card in encrypted form under the working key to the acquirer computer.