Abstract: A value transfer system of at least one VCD (Value Carrying Device) (1) and at least one VAD (Value Accepting Device) (2), the VAD (2) having a memory (53) for storing at least an aggregate value (28) of previous accepted values and a device for transferring a claiming message (13), the VCD (1) having a memory (52) for storing at least a balance value (7) and a device for transferring a proving message (14), wherein the VAD (2) includes into the claiming message (13) a transaction value (20), a previous aggregate value (21) and a corresponding previously computed proving cryptogram (22), the VCD (1) computes and includes into the electronic message (14) a transaction proving cryptogram (35), computed on the basis of the previous aggregate value (21), the corresponding previously computed proving cryptogram (22) and the transaction value (20), and the VCD (1) computes the at least one transaction proving cryptogram (35) only if it has established the correctness of the received previous aggregate value (21) by

Abstract: In a card charging system, especially for public transport services, there is included: (a) a card read/write unit for receiving one or more prepaid or credit cards; (b) a transaction recording-payment facility; and (c) a security module located between the card read/write unit and the transaction recording-payment facility, the recording-payment facility operable to receive signals from the security module to enable a purchase to be made in return for an amount of credit debited from said one or more cards, wherein a contactless concessionary card reading subsystem is connected to the security module, in addition to the card read/write unit for prepaid or credit cards. The system provides the benefit that it is capable of accommodating concessionary card reading subsystems and determining appropriate debiting associated therewith in addition to improved transaction recording and enhanced security.

Abstract: In a card charging system, especially for public transport services, a host ticket facility is operable by both credit cards usable at a card read/write device and concessionary payment cards usable at a contactless card reader, and a security and transaction device located between the card readers and the host facility stores in separate storage devices full fares and concessionary fares which the host facility is able to calculate. A card charging system, especially but not exclusively for payment of public transport fares is described, having one or more card readers and a security and transaction device connected between the card reader(s) and a host facility and for transmitting information back to a clearing centre, wherein the security and transaction device includes a number of non-volatile storage devices for error counting and transmitting related performance data back to the clearing centre.

Abstract: In a card charging system, especially for public transport services, a host ticket facility is operable by both credit cards usable at a card read/write device and concessionary payment cards usable at a contactless card reader, and a security and transaction device located between the card readers and the host facility stores in separate storage devices full fares and concessionary fares which the host facility is able to calculate. A card charging system, especially but not exclusively for payment of public transport fares is described, having one or more card readers and a security and transaction device connected between the card reader(s) and a host facility and for transmitting information back to a clearing center, wherein the security and transaction device includes a number of non-volatile storage devices for error counting and transmitting related performance data back to the clearing center.

Abstract: A security device for use in a card charging system where a service or product providing facility issues services or products by the use of credit from a card. The security device comprises signal transmission means for delivering signals to a purchasing facility to enable a user to acquire a service or product dependent on the credit debited from a card, a record keeping subsystem to certify the credit debited from the card and to identify which account is to receive the debited credit and signal processing and output means for generating signals indicating a successful transaction. The signals may be encoded by use of encryption techniques. A separable security subsystem is provided to ensure a record of transactions is available if power fails on the main security device.