ARCHITECTURE OF SIMPLIFIED HARDWARE REQUIREMENTS FOR BANK CARD PAYMENT TRANSACTIONS IN A LARGE GROUP OF CLIENTS, TRANS- ACTION TERMINAL UNIT, EXTENDED FUNCTION SIM CARD, AND METHODS FOR INDIVIDUALISATION AND PERFORMING TRANSACTIONS The present invention relates to an architecture of simplified hardware require- ments for bank card payment transactions in a large group of clients, in which clients and service providers exist, the clients keep a bank account at one or more issuing banks which are authorized to issue bank cards, and have a mobile bank card pro- vided with a customary bank card identification information, a GSM mobile phone, and a valid SIM card for enabling access of the GSM services, the service providers keep a bank account at one or more acquiring banks, and have a unit with a function of a transaction terminal, and a device adapted for receiving system messages.

The invention further relates to a transaction terminal unit adapted for data veri- fication of a bank card and/or management of an authorization message received through a communication channel, the transaction terminal is installed in an archi- tecture of simplified hardware requirements for financial transactions in a large group of clients, in which clients and service providers exist, the clients keep a bank ac- count at one or more issuing banks which are authorized to issue bank cards, and have a mobile bank card provided with a customary bank card identification informa- tion (or some other mobile payment instrument to be described later), a GSM mobile phone, and a valid SIM card for enabling access of the GSM services, the service providers keep a bank account at one or more acquiring banks, and have a unit with a function of a transaction terminal, and a device adapted for receiving system mes- sages.

The invention further relates to an extended function SIM card for a GSM mo- bile phone of a subscriber, which in addition to a memory required for functions to make GSM services available, comprises a separate second memory for storing ad- ditional data, and a control unit (CPU) adapted for at least performing logical opera- tions.

The invention further relates to a method for individualization or as we further call personalization of an extended function SIM card used in a GSM mobile phone of a subscriber, wherein the SIM card in addition to a memory required for functions to make GSM services available, comprises a separate second memory for storing ad- ditional data, and a control unit (CPU) adapted for at least performing logical opera- tions. The second memory has a preformatted file structure.

The invention further relates to a method for performing transactions by making use of the aforementioned architecture.

Techniques for performing payment transactions through mobile phone systems are known in the prior art. However, these proposals either provide a low level secu- rity with respect to verification of whether the action has been initiated by an author- ized person, or significant technical changes of the system components are neces- sitated, e. g.: radical changes of the mobile phones or the accounting/auditing system of a bank.

The aim of the present invention is to provide an architecture and system which enables convenient and secure bank card payment through an existing mobile phone network when an electronic bill is presented. With the architecture and system ac- cording to the present invention safe payment is enabled in situations where use of a bank card is inconvenient or risky or is not possible at all, for example in case of paying the bills received from a utility company or paying the charge for mobile phone calls ; buying at petrol stations, in restaurants, in other shops or through the Internet.

The essence of the invention can be summed up as follows : - the architecture according to the invention provides a transaction collecting channel included in the existing servicing environment of bank card payments; - the PKI based architecture according to the invention provides safe pay- ment, where a SIM card represents the safety element on the client-side ; - the architecture according to the invention comprises a virtual POS means for accomplishment of a POS-like bank card payment in a GSM and WEB environ- ment; in the system according to the invention the conventional SIM card is re- placed by a multi-application intelligent card having SIM functions at the same time.

The architecture according to the invention supports electronic bill presentation and subsequent payment, except when a client (the card holder) initiates a transac- tion from the menu of his mobile phone in order to provide ballance for his prepaid GSM card. A common advantage of these accomplishments is that the card holder does not need to key in the data of the transaction for initiating a payment transac- tion, which may be a source of error, therefore it is more comfortable for the client.

Communication between participants is performed by means of SMSs. As a re- sult of the applied cryptography each of the messages has a size of 1 SMS-block.

The number of SMS-blocks used during a complete payment transaction depends on the particular business requirements of the transaction type; this number changes between 2 and 5.

The essence of this kind of service is that the customary, presently known bank card payment system is translated to an environment where transmission is per- formed through the GSM network, security is guaranteed by asymmetric cryptogra- phy, client identification is accomplished by means of a SIM card, and the pay termi- nal is represented by a virtual POS terminal in a mobile payment center.

In different business environments and situations different services are feasible.

Here are a few examples of these services: - Top-up of a prepaid GSM card. A GSM client is able to fill up his own pre- paid card by initiating a transaction from the menu of his mobile phone so that his bank account is immediately debited with a determined sum.

- Settlement of a GSM (subscriber's) bill. The GSM client when receiving his bill presentation from his GSM provider settles his bill monthly by making use of his mobile bank card.

- Paying utility bills. Upon receiving an electronic bill sent from a utility com- pany at regular times, the client is able to settle the bill without paying in cash.

- Web-shop. Secure buying through the Web is enabled, where control of the logistic functions is performed at the Web interface, payment is performed through a GSM device identified in the system, to an also identified object, that is, to a unit with a function of a transaction terminal, and keeping a bank account at one or more ac- quiring banks.

- Buying from a catalogue. This may be done in like manner as buying through the Web. A secure way of paying without cash for articles chosen and or- dered from catalogues, giant posters, etc.

- Mobile paying in shops and restaurants. Similarly, it is a secure way to settle an account in these places.

In the system according to the invention the SIM card is provided with the fol- lowing operational elements: - GSM application ; - GSM service identification data; - application according to the invention; - individual SIM card identification (SIM ID or CSN); - cryptographic public key and private key.

The participants of the mobile bank card service are the clients of a bank (card holder) and the issuing bank. The client applies for a mobile bank card at registration.

This can be done either personally at a bank, or, if the bank supports distant opening of an account and application for a bank card, then, for example when applying for a new SIM card, the client may receive the documents necessary for opening of an ac- count and for handling in an application for the bank card at the customer service point of the GSM provider. The client fills in the registration form for a mobile bank card, then this form is forwarded to the bank in a secure manner well known and ap- plied in the art. Then the bank generates an entirely virtual mobile"partner-card", which is connected with the existing bank account of the client. Bank card and SIM card identification data connected to the mobile partner-card are transferred to a bank card data collecting means operated by the system in the bank. The bank card data collecting means generates the cryptogram for the mobile partner-card and sub- sequently to proper cryptographic steps, together with the SIM identification data, preferably through a bidirectional cryptographic interface transmits it to the payment center. The mobile payment center enters the mobile partner-card cryptogram onto the SIM card of the client. Upon completion of registration the device of the client is adapted to payment.

The system according to the invention comprises a number of subsystems which are separate from each other in terms of management and operation. These are the next: - SIM card preparation - Issuing payment instrument and management - Transaction and message processing - Cryptography - Telephone-side software Archiving - GRM subsystem A precondition of issuing payment instrument is that the user should have a SIM card containing the application according to the invention. Therefore, the client may go for example to the nearest point of sale of the GSM provider and hand in an appli- cation for the service. Then the client receives a (not yet activated, but registered in the system) SIM card having a preformatted file structure and containing the GSM application. Transactions may be performed by using various kinds of payment in- struments, e. g.: bank card, bank account, etc. To initiate a transaction with a par- ticular payment instrument, the payment instrument should be registered beforehand at the issuing institution, for example at the issuing bank, as a result of which the particular payment instrument is listed on the SIM card of the mobile phone.

When applying for a bank card or bank account based payment instrument, the client will see the issuing bank. If the client does not yet have an account, then opens one, however, if he already has an account, then-in case of a bank card type pay- ment instrument-he may give an order for a mobile partner-card. When applying for a payment instrument, besides the usual data, the client must give information about his SIM card identifier (CSN) and the telephone number of his mobile phone.

In case of bank card based payment instrument the information system of the bank generates data for the client's mobile partner-card in a customary procedure, with the difference that creating an effective bank card is optional for the bank.

As a next step, the bank initiates transfer of data of the payment instrument to- wards the mobile payment center through an element of the system according to the invention, which element in this context constitutes a periphery of the same kind as the card-manufacturing machine.

A functional diagram of the system according to the invention will be described through an example by means of the attached drawing.

Figure 1 shows the operational processes and the functional lay-out of the ar- chitecture.

In figure 1 service provider 2 enters the system as an owner of a virtual POS terminal 5. Virtual POS terminal 5 physically forms a marked electronic part, a stor- age domain of a mobile payment center 4. Each of the virtual POS terminals 5 in use must have an individual identifier, which, during an exchange of messages with client 1, appears as the name of the service and the service provider 2. Since the identifier may not contain only numerical values, it is preferable to do its selection similarly to doing a domain name registration. As with customary POS terminals, in case of op- erating a virtual POS terminal 5, an account kept in a bank must exist for receiving transfers. For this reason, upon opening an account, which in the customary way takes place in a bank, virtual POS terminal 5 identifier must be selected.

As a first step in the process of issuing and registering the mobile payment in- strument, the future owner of the virtual POS terminal determines a name according to his wish, however, choosing a name is not a fundamental requirement. Service provider 2, for example a tradesman, may request the system to generate a virtual POS terminal identifier for him automatically. In either case, an attempt is made for selecting a"name"as identifier, since it may happen that the selected name has al- ready been reserved. If the administrator of the bank attending to service provider 2 is in direct contact with mobile payment center 4 (e. g.: through the Internet), a check may be performed immediately through an interface of the mobile payment center set apart for this purpose in order to determine whether the name is reserved or not. If it is not possible, then the tradesman obtains information about the status of the name he selected for the virtual POS terminal later, through the bank. When the attempt for selecting a name is successful, then this selected name is considered by the system as reserved for a period of time determined collectively by the bank and the trades- man, and requests for the same name originating from other sources are rejected.

Reservation ceases to exist when the determined period of time expires, or it be- comes definitive when request of the client for operating a virtual POS terminal is ap- proved by the bank.

For functioning of service provider 2 the following data are needed: - Virtual POS terminal identifier - One or more TID identifiers (virtual POS terminal identifiers) depending on the load - Bill number of service provider 2 for transactions of a transfer type - Data relating to communication channels through which transaction ac- knowledgements (E-Slip) are transmitted - Restrictions relating to payment instrument selectable by the users TID identifiers are needed for bank card based transaction authorization which may be executed for example through a known protocol BASE24. A TID identifier is issued by a bank card authorization center 11. It is possible for service provider 2 claiming for a virtual POS terminal 5 to make a request for more T ! Ds for the same virtual POS terminal 5. Load on a virtual POS terminal may be decreased by initiating parallel transfers using different TlDs, the maximal number of transfers depends on the number of channels granted by the bank card authorization center 11.

Through restrictions relating to payment instrument service provider 2 may clearly determine which type of payment instrument of which issuing institution (bank) he is ready to accept. Several categories relative to payment instrument may be de- termined, which upon presenting the bill makes selection of other restrictions (categories) per client possible.

In case of big service providers initiation of registration may be completed on paper. When telephone holders are considered as potential service providers 2 in the system according to the invention, then virtual POS terminal registration should be automatized, for this an Internet based interface may be used.

For forwarding the registrations of mobile bank cards and virtual POS terminals towards the mobile payment center, it is essential to install a work station as a part of the system according to the invention, which is connected to the system responsible for processing of banking demands (payment instrument, virtual POS terminal). This computer is physically connected to the computer network of the bank, however, ac- cess to the network for the work station is not needed. Preferably, the work station comprises a chip card reading unit, a key card and a communication unit which guar- antees communication of data with a central unit according to the invention.

Information system of the bank makes demands for payment instrument and virtual POS terminals according to the invention accessible in a shared directory of the work station. Exchange of data is executed through text files having a determined format (a file structure comprising own control codes). Demands for mobile cards and virtual POS terminals are placed into the same input directory. The time of generating a file and the number of records in the directory are determined by the number of ac- cumulated demands and the date of the earliest demand. Scheduling of data transfer through files is a duty of the bank.

Components (presenting individual registration types, e. g.: payment instrument, virtual POS terminal) running in mobile payment center 4 control the bank's input di- rectory from time to time and compare it to the file catalogue recorded in the system, and when new records are found, process of these files are initiated. As a first step of this process, the component decodes the file by making use of the private key of the mobile payment center, then the bank's public key of the mobile payment center, and after that, depending on the type of registration, the component transmits the file to the respective processing component.

Generation of response files to be transmitted to the bank is a task for the com- ponent which is responsible for acknowledgement of registrations later ending with- out success.

If there is no registration for the SIM card, then the given SIM card is activated in the system, and the phone number obtained from the GSM phone number issuer 3 according to figure 1 is saved. In case of successfully registered SIM card, the for- warded phone number is compared to the phone number presently registered in the system, and when there is a disagreement, an error message is sent to the bank's acknowledgement buffer. Upon a successful SIM card activation the component performing registration of the payment instrument for the bank, generates a registra- tion message, and, addressed to the phone number belonging to the SIM card, transmits it to the message request server component. The component which per- forms processing of requests for bank cards keeps a record of the individual opera- tions, and the file, into which the individual registrations for payment instrument ar- rive, can be identified by make use of these records. This registration is mainly needed for archiving and data retrieval from archives. Responses to messages ar- riving from the user's phone in relation to registration of payment instrument are evaluated by the relative component of the message processor.

The process of registration means activation of a virtual POS terminal identifier in the system according to the invention and execution of subsequent verifications needed for managing of a bank's POS, as well as activation of keys belonging to TIDs, in each case. Information relating to success or failure in activation of a virtual POS terminal is contained in a response file. After all POS terminal records of the source file have been processed and simultaneously with this results of the record- ings are available, the response file is placed into a directory of the mobile payment center 4 containing bank acknowledgements.

The component which transmits acknowledgements running within mobile pay- ment center 4 is responsible for generating acknowledgement files for unsuccessful registrations relative to payment instrument and for copying them into the bank's out- put directory. Accidental false demands for payment instrument are temporarily stored in the bank acknowledgement buffer. A process performed from time to time ensures that an acknowledgement file is generated for these unsuccessful registra- tion attempts being in the buffer. Then, the aforementioned acknowledgement files relative to registration of a payment instrument as well as a virtual POS terminal are coded by making use of the private key of the mobile payment center 4, the public key of the bank, and transmitted to the bank by the component.

The transmitted files are taken into a directory of the mobile payment center 4 shared for response files. Acknowledgement transmitting component running in mo- bile payment center 4 decodes the newly arrived files and moves them to a directory shared for the bank's information system.

Transaction processing-logically and in terms of dependence on external re- sources-consists of several separate actions. Modules (components) performing the individual actions are applications which may run independently. The individual mod- ules communicate each other through asynchronous waiting queues, in this way they may operate independent of availability of other modules. Components (modules) operate on application servers in a component running environment, through which new component replications may be initiated or connection to an already running module replication is enabled through connectors. A system of frames co-ordinates the modules participating in transaction processing, keeps record of application serv- ers and module replications running on these servers.

Through the system of frames tracing of processes running on module replica- tions is enabled by making use of individual status tables featuring the individual modules. Through the message register information may be obtained about events of great importance taking place in the module replications. Module replications send the messages to the system of frames through a uniform message sender compo- nent. Each of the events has an individual message code and category designation within the whole system. Filters may be used for filtering individual message codes and categories. By making use of the waiting queues status tables, capacity and changes of the capacity are traceable.

The outlined operations make precise keeping track of all of the substantial process being performed in the system possible. Automatism and alerts based on them enable rapid response to unexpected events. Response may be effected on application level in a predictable case, and in an unexpected case it is effected by the administrators.

The SMS communication layer controls receiving or sending of packets ac- cording to the direction of message packets travelling in data channels. There are different data channels reserved for data moving in and out respectively. According to the direction of data-travel different components are used by the system.

Incoming data are filtered by a blacklist filter, and the messages arriving from source addresses which are found definitely disabled, are discarded at once. Mes- sages arriving from sources which are temporarily designated for blacklist, are put in a separate error register with the source marked; the content of the register may be analyzed later. A routine counts the erroneous packets arriving from the same source, and when the number of these packets exceeds a threshold value, the sending source is definitely entered on the blacklist.

The blacklist filtered (still coded) raw message packet together with the respec- tive data-e. g.: the individual message identifier-is sent to the incoming messages buffer. On the one hand, the primary function of the message buffer positioned be- hind the communication layer is to make the communication subsystem independent from being available to other components of the system, on the other hand, it makes parallel processing simpler.

Subsequent to encryption, messages to be sent to users, together with data as- sisting in communication and registration respectively are transmitted to the outgoing data buffer. Components which are responsible for transmission of messages re- move the packets sent to the data channel handled by them one after the other from the outgoing data buffer, then the already prepared message is forwarded to the destination address by mobile payment center 4.

A task for an SMS communication module may be to make connection with the SMS center of the mobile payment center 4 and service provider 2 and to forward and receive transactions to and from the center respectively. The mobile payment center 4 substantially consists of a plurality of virtual POS terminals 5, which are lo- cated physically separate from client 1, service provider 2, GSM service provider and issuing/acquiring banks.

Messages arriving at mobile payment center 4 are decoded on the basis of keys determined by the SIM identifier. Messages restored in their original form are con- verted according to the contained type and the fields are passed on to the processor components. The message processor may request the messages running in several replications from the input buffer. Each of the messages describes one operation.

Types of messages arriving at the mobile payment center and processor components representing the message are as follows : - payment instrument registration acknowledgement - acknowledgement of activation and deactivation of application - order for payment, refusal complaint, acceptance (in case of bill presenta- tion) initiation of sending a bill presentation to another phone in the system.

The order of payment preparatory component, after a control of the form and possibly the content of the message fields, inserts data in transaction buffer 7 con- taining transactions. The transaction types whose structure is different from each other to some extent are handled together. Depending on the result of the transaction preparation an answer message is created, which is transmitted to the outgoing mes- sage buffer, addressed to the sender source. The answer message may be an error message (if the message failed during control of the content) or an interim acknow- ledgement (in case of delayed transaction).

In case of initiation of sending a bill presentation depending on the status of the target telephone in the system an error message is transmitted to the initiator, or a bill presentation is transmitted to the receiver. This bill presentation formally equals to bill presentations otherwise initiated on server side and has the same features.

The individual types of messages are different from each other as regards their function and structure. The structure of the types of messages is determined in the structure description table. The messages are marked by a type identifier, on the ba- sis of which processing on the receiver side is able to identify the structure (sequence, length and type) of the fields of the message from the structure descrip- tion table.

In case of a 1024 bit key RSA asymmetric encryption algorithm the cryptogram generated with the employed encryption method has a size of 128 bytes. The maxi- mal size of a packet through an SMS based communication channel is 140 bytes.

When processing a transaction, transaction buffer 7 stores transaction requests which arrived in the system and are prepared by the message processor. The buffer administrator requests transactions with the appropriate status from transaction buffer 7. Buffer administrator manages waiting queues, numbers the transaction re- quests, monitors the expiry of delayed transactions, re-schedules the transaction in case of an unsuccessful attempt and registers the number of tries. Each transaction request contains the date of expiration, which with certain types of transactions may be determined by the service provider, otherwise it equals with the date of registra- tion of the transaction. In case of an unsuccessful transaction processing the buffer administrator may be requested to replace the transaction request into the waiting queue by performing a count shift, so that the serial number of the request buffer will get a value which is the sum of the greatest serial number which has not yet been allocated plus the shift. Upon repeated replacement of a transaction request the buffer administrator automatically increases the number of the attempts made for processing of the registration. The buffer administrator informs the processor about the number of the unsuccessful attempts as a result of which the transaction request may be declared definitely erroneous.

The channel administrator scheduling the initiations of transactions always re- quests a transaction for a disengaged channel type. The buffer administrator must take into consideration what type of payment instrument may be used for transfer through the free channel type, and select a transaction request from transaction buffer 7 according to this consideration.

Further, in case of bank card based payment instrument it must be determined whether a free (momentarily not used in parallel transfers) TID exists among the ones allocated to the virtual POS terminal 5 involved in the transaction. In case of successful transaction selection, the buffer administrator must reserve the request, or in case of a bank card the TID in question.

Upon accomplishment of the transfer the processor requests the removal of the transaction from the transaction buffer 7, in this manner the reserved TID becomes free.

Execution of a transaction request through the authorization center (s) of the bank constitutes the bottleneck in the whole transaction processing. A transaction with the authorization center may be effectuated through number of communication channels at the same time. Communication channels can be classified according to the applied communication protocol and the admitted payment instrument (bank card, bill number, etc.). In order to perform an optimal transaction processing, with considering the bottleneck in the communication through the authorization centers, scheduling of the processing is determined by the available data channels. Schedul- ing of the processes is performed by the channel administrator. As a result of the disengagement of a certain type of channel a request is transmitted to the buffer ad- ministrator for a subsequent transaction in compliance with that type of channel. If no transaction applicable to processing is received from the buffer administrator, then a transaction is requested for the next channel in the list of free channels. If the end of the list is reached, selection of the channels is recommenced, in this way it is en- sured that each channel type is provided with transactions approximately with the same frequency.

After a successful transaction request the transaction together with the data re- ceived from the buffer administrator are transmitted to the transaction processing component representing the given channel. After transmission of data, the channel administrator immediately receives control back, in this manner it may continue ex- amination of the free channels.

A transaction request is performed by the transaction processing component through a communication channel personalized by this component. The task of the transaction processing component is to analyze the result of the transfer, and is liable to instruct the buffer administrator to perform further steps depending on the result of the transfer, that is, to remove transaction request from the waiting queue if the op- eration was successful, to delay the request (serial number shift) in case of commu- nication error, and to declare the transaction request invalid in case of an unman- ageable error. As a result of a successful transaction the processing component generates so called E-Slips 9,10, which are transmitted to the outgoing message buffer addressed to the user and also to the operator of the virtual POS terminal. Af- ter generation of the E-Slip 9,10 the transaction processing component sends a noti- fication to the channel administrator indicating that the represented channels is free again. Processing of transaction requests run parallel (on different lines), in accor- dance with the number of communication channels in the system.

The component performing the transfer obtains transaction data, TID and the number of the communication channel as parameters.

In the system according to the invention each of the acquiring persons (tradesman) are provided with a virtual POS terminal identifier. This virtual POS ter- minal identifier is provided with at least one terminal identifier (TID), which is regis- tered in the system of the bank card authorization center 11. Depending on the load, a virtual POS terminal 5 may have a number of T ! Ds. Transactions arriving at service providers 2 are authorized through the TID. When registering a given virtual POS, similarly to a"normal"POS, transaction authentication keys of the TID are down- loaded through the bank connection (leased line, switched line modem).

Virtual POS terminal 5 obtains card data, the total amount of purchase and the TID of service provider 2 from the system according to the invention. Virtual POS terminal 5 examines card data and expiration. If one of them precludes purchase, then the transaction is rejected, otherwise a transaction is formed from the above data which is forwarded to the authorization center 11. If the authorization center ac- cepts the forwarded transaction, then sends a notification about acceptance to the system according to the invention, otherwise rejects the requested transaction.

Reminders sent to telephones will take the place of conventional postal-orders, printed money orders in the system for settlement of an electronic bill. Upon settle- ment of the electronic bill, the sum to be deducted from the account of client 1 is credited to the account of the reminder sender service provider 2 (for example a wa- ter/gas/power supplier).

Service provider 2 initiates a reminder towards the telephone number of client 1 having a subscription according to the invention. The reminder briefly contains the cause of demand, the due date of payment and the sum to be paid, and with these it is sent to mobile payment center 4. Based on preliminary agreement between service provider 2 and mobile payment center 4 service provider 2 may select the type of the payment instrument to be used by the client for settling the bill.

The cryptographic element used in the system ensures proper cryptographic protection for data flowing in the system.

Preferably, the selected algorithm is the known RSA algorithm with a key length of 1024 bits. RSA algorithm uses a public key and a private key for encryption. Mes- sages coded with a private key can be read only with a public key, and messages coded with a public key can be read only with a private key. In this case any person who knows the public key may send a message to the owner of the private key. The authenticity of the sender can not be guaranteed in this case. The dual key is needed to solve this problem of authentication. The sender party codes the message with his own private key, then codes the so coded message with the public key of the receiv- ing party. In this case the message can be unpacked only by the receiving party, by using his own private key first, then the public key of the sender. In this manner the problem of authenticity is solved.

The above described embodiments, particularities, programming and concre- tized computing methods merely serve as examples. Modifications and alternative embodiments can be made without departing from the scope of the present invention as defined in the appended claims.