In developed countries, at least, electronic and magnetic media of various kinds are very widely used in banking systems: nearly everybody has one or more credit or debit cards, for instance. Such media commonly include unique identifiers such as card and issue numbers, signatures and/or photographs. However, even when their use is subject to entry of a personal identity number (or"PIN") it is still possible for them to be used by unauthorised persons.

It is a first object of the present invention to provide a banking system with improved security against unauthorised use.

Partly because of the security limitations of conventional banking systems, the use of credit and debit cards requires every transaction to be communicated to an accounting subsystem managing the users'accounts.

Typically a user's account details are extracted from his card at a point-of- sale (POS) terminal and transmitted to the accounting subsystem, and the transaction is not completed until authorisation is sent back from the accounting subsystem. This contrasts with the speed and simplicity of a cash purchase and means that conventional card-based systems are much too unwieldy for the commonplace purchase of small items like newspapers, parking permits and so forth.

It is therefore a second object of the present invention to enable cards or similar portable devices to be used conveniently for such commonplace purchases.

Thus according to the invention there is provided a banking system comprising: (a) accounting means containing account control information, being information about accounts of the bank's users whereby transactions associated with those accounts are controlled ; (b) a plurality of portable register devices each ascribed to an authorised user and including (i) identification means such that each ascribed register device is inoperative unless and until its authorised user is identified by that register device and (ii) a register for storing a value representative of a cash amount; (c) communication means for passing account control information between the accounting means and the register devices; and (d) transaction means operable by an identified user of a said register device alternatively to effect (i) a transaction of a first kind in which said value is increased to the debit of the user's account or said value is decreased to the credit of the user's account and (ii) a transaction of a second kind in which a said value or part thereof is transferred to another register device of the system;

in which system transactions of the first kind are controlled by said account control information and transactions of the second kind are not so controlled.

Those skilled in the art will appreciate that the identification means of the invention provides improved security in comparison with conventional banking systems. And this improved security allows the system to support certain transactions without centralised control, thereby enabling users to make payments, eg of small sums for commonplace purchases, as quickly and as easily as with cash. In effect, the invention combines the benefits of conventional card purchases (which are secure, offer credit, and save the user from carrying large sums of money) with those of cash purchases (which are quick, immediately monitored, and not burdened with an administrative overhead).

The convenience of transactions of the second kind is an important benefit of the invention. International patent application WO 97/45814 A1 (Vazvan) describes a system in which electronic payments can be made directly from one terminal of the system to another, rather than via a network, but which specifically requires for each such payment that the payer's terminal receive the payee's account control information (namely account number and contact codes) before the payment is effected. Those skilled in the art will note that such payments, being subject to account control, are quite different from the cash-equivalent transactions of the second kind provided by the present invention, and lack the benefits of

cash-type payments. In Vazvan's system, every transaction is controlled (with an administrative overhead in record-keeping etc, a need for communications capacity, and consequent delay) whereas the present invention avoids all this for transactions of the second kind, which are cash- equivalent.

The register devices of the present invention may comprise electronic and/or magnetic cards. Alternatively the register devices may comprise mobile telephones, in which case the communication means preferably comprises a cellular radio network.

Preferably the transaction means is operable at a said register device, which may include a keypad whereby the transaction means is operable.

The transaction means may be operable to effect a transaction of the second kind with a device not being a portable register device of the system - eg a POS terminal. Also a register device of the system may include means whereby it may be connected to another device-of the system or otherwise-for transactions of the second kind.

Preferably the identification means includes reference means for holding a representation of an authorised user's fingerprint or other biometric characteristic, input means for inputting a biometric characteristic of a would-be user, and comparator means for comparing the input characteristic with the reference representation to check that the would-be user is the authorised user.

The register devices include exchange means operable to alter the currency of said cash amount.

Especially for use by visually impaired users, a said register device may include means audibly to indicate operation of the identification means, the communication means and the transaction means.

And in case banks wish to charge for use of the system, the system may include charging means operative to charge an authorised user in relation to usage of his ascribed register device.

Other aspects of the invention will be apparent from the following description, which is made by way of example only with reference to the accompanying schematic drawing in which- Figure 1 is a block diagram of a banking system according to the invention; Figure 2 is a block diagram of a register device of the banking system of Figure 1 ; and Figure 3 is a block diagram of two register devices involved in a banking transaction.

Referring first to Figure 1 this shows a banking system comprising an accounting subsystem 10 and three portable register devices 12 (out of a large number thereof). Each register device 12 includes a transceiver 14 arranged to be in communication with a transceiver 16 of the accounting subsystem 10 for exchange of information about banking transactions. The

transceiver 16 is operatively connected by a network 18 to a plurality of stores 20 holding users'account details.

Each register device 12 includes reference means 22 holding a digital representation of an authorised user's fingerprint. A detector 24 is arranged to read and digitise a fingerprint of a user, and a comparator 26 compares the digitised input from the detector 24 with the digital representation of the authorised user's fingerprint held in the reference means 22. The transceiver 14 is connected to the comparator 26 so as to be operative only when the input from the detector 24 is the same as the representation in the reference means 22. In other words, a user can operate the transceiver 14 (and thereby access his account) only if he proves his identity by way of the detector 24.

Thus the banking system of Figure 1 improves the security of each store 20 by checking the actual presence of the authorised user each and every time an attempt is made to access the stores 20. And it will be understood that the individual register devices 12 may have different authorised users, eg one for each, so that even an authorised user of one register device 12 cannot access the corresponding store 20 by using another authorised user's register device.

Referring now to Figure 2, this shows a portable register device 30 (which is one of a large number for use by a bank's customers) including a transceiver 32 which is operable only when a comparator 34 determines that a user's fingerprint input and digitised by a detector 36 is the same as

a digital representation of an authorised user's fingerprint held in reference means 38. The transceiver 32 is operable to transmit data to and receive data from a central transceiver 40 of an accounting subsystem 42, and the central transceiver 40 is operatively connected to a plurality of stores 44 storing account balances and other records of the bank's users.

The register means 30 includes a keypad 46 whereby a user can input information for transmission to the accounting subsystem 42 by the transceiver 32 (subject to authorisation). Thus a customer can access his bank records. Further, he can arrange a release of funds from his account, as will now be described in more detail.

The register means 30 includes a register 48 which stores a value representative of a cash amount. The (authorised) customer can increase this amount by signaling the accounting subsystem 42 to draw on his account. Similarly the customer can add to his account by signaling the accounting subsystem 42 to draw down from the register 48. The register means 30 also includes exchange means 50 operable from the keypad 46 to change the currency of the amount held in the register 48.

Those skilled in the art will now appreciate that the register means 30 is as good as banknotes and coins in terms of value and portability, and more convenient in its capacity for currency change.

Figure 3 shows how the invention can cater for person-to-person financial transactions, even of small value. Suppose a first customer wishes to make some payment to a second customer. He connects his register

device 60 to the register device 62 of the second customer. The register devices 60 and 62 are essentially identical (and the same as the register device 30 of Figure 2) and each comprises a transceiver 64, reference means 66, a detector 68, a comparator 70, a raster 72 for a value representative of a cash amount, exchange means 74 and a keypad 76.

The register devices 60 and 62 also include male/female connectors (not shown) which enable the two register devices 60 and 62 to be connected together and establish a two-way connection 78 between their respective transceivers 64.

The first customer now puts his finger on the detector 66 of the first register device 60 and this is compared with the reference representation held therein. Assuming the first customer's fingerprint accords with the reference representation, the transceiver 64 of the first register device is enabled, and the first customer can then use the keypad 76 of the first register devices 60 to instruct transfer of the required payment to the second register device 62, up to the value held by the first register device 60. The result is an electronic transaction equivalent in all respects to the first customer's passing cash to the second customer.

It will be noted that transfers direct from the first register device 60 to the second register device 60 do not require any communication with an accounting subsystem or any other central banking facility. Thus such transfers are quick and easy, and the communication network is not overloaded.

Numerous additions, modifications and adaptations of the systems described may be made without departing from the essence of the invention. First, as will be well understood, information transmitted should be encrypted for security, and a wide variety of encryption technologies are available for this purpose. The register devices may be embodied as smart cards, or possibly as electronic calculators which may utilise Bluetooth or other infrared communications technology. Most conveniently, however, the register means may be included in a mobile telephone using, say, 3G/GPRS communications technology and thereby giving (authorised) mobile telephone users the ability to access their bank accounts remotely for credit and debit transactions and to transfer cash equivalents direct to other devices. Although not shown in the drawings, each register device may include means such as a dual tone multi-frequency (DTMF) generator to produce tones indicating each action performed on or by the register device-eg yes/no signals from the identification means, operation of a keypad, completion of transactions and so forth. To allow banks to charge users for use of the system, charging means may be provided to record the usage of register devices (number and/or level of transactions, of both the first and second kinds) and levy charges against users accounts in relation thereto. Finally, banks, post offices and other like institutions could issue a register device means reloaded with a cash value and programmed with foreign exchange rates, to function as a versatile travellers'cheque whereby a user may make cash equivalent purchases in a variety of countries Other possibilities will be apparent to those skilled in the art.