Abstract:
An offline code-based reload device and method for adding value to a reconfigurable memory storage means in a portable storage medium. Reload is effected using a reload device not directly connected by telephone or any other communication network to a value supplier. The system uses a “one time use number” (“OTN”) generated by a computer program containing an algorithm containing information on the value to be added and a transaction sequence number (“TSN”). Upon presentation of the portable storage medium to the reload device and entry of the OTN into a numeric keypad, the reload device decodes or disassembles the OTN to verify its authenticity, validate that it was created for the specific portable storage medium presented to the reload device and to verify through the TSN that the OTN has not been previously used to add value from the receiving reload device or any other reload device. The reload device further extracts the value from the OTN, adds the value to a selected purse on the portable storage medium and loads a new TSN to the portable storage medium.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application is a division of U.S. patent application Ser. No. 10/462,520 filed Jun. 16, 2003, which is incorporated herein by reference in its entirety. 

   FIELD OF THE INVENTION 
   This invention relates generally to a low cost means of adding value to portable media such as “smart cards” of microprocessor or encrypted memory types, key fobs, magnetic stripe cards or any other form factor that permits electronic read/write functions that can be used to replace coins in exact change payments of small amounts spent by a consumer. 
   BACKGROUND OF THE INVENTION 
   Traditionally, exact change micropayment transactions such as vending machines, pay-for-use laundry machines, pay telephones and public transit access were facilitated through the use of coins. A user would obtain a sufficient number of coins or tokens of the correct denomination to obtain the desired product or service. Bill changers were sometimes provided but are expensive to install and maintain, and are prone to burglary with the result that coins are not generally available to the public at the place where the exact change micropayment transaction is to take place. 
   In recent years alternatives to coins for micropayments have been developed to reduce the nuisance of carrying or searching for exact change. These alternative payment forms have typically been such media as disposable smart cards or magnetic swipe cards. These media typically have a preloaded value when purchased from a vendor. There are major disadvantages with these micropayment media. The first disadvantage with these micropayment reload devices is to the user. With prepaid/preloaded cards, the user must purchase cards in fixed cash increments creating the problem of having residual non-useable value left on the media, depending on the vend rate for the desired product or service. The media is disposable which adds cost to the issuer. There are also additional costs associated with distribution, most notably, payments to retail vendors for distributing such media and security issues with cards that have preloaded value. 
   Reloadable microchip media such as smart cards and key fobs, and encrypted magnetic media such as swipe cards have the potential of overcoming all of these problems with a number of additional benefits including the ability to load non-preset or fixed amounts, facilitating a low cost means of granting repayments of error amounts or lost amounts thereby saving the costs of mailing small refund cheques and placing additional applications such as loyalty programs on the media. 
   Historically the replacement of coins by reloadable smart cards and other electronic micropayment media has been prohibitively expensive due to the high cost of reload devices such as currency acceptors to media and credit/debit card acceptors to media. The high cost of such reload devices has limited their availability resulting in a lack of infrastructure to support the widespread adoption of reloadable micropayment media. 
   Currency acceptors are high cost, armoured, mechanical reload devices prone to breakage and counterfeit money and carry substantial risks of burglary and vandalism. They must be placed in high security locations and the funds accumulated in the boxes need to be collected, counted and presented to banks in a secure environment at considerable cost. 
   Debit/credit card reload devices while lower in cost than currency acceptors initially carry the ongoing costs of networking to telephone or other remote communications systems in order to validate the financial transactions. In addition, these are not usable by people who have neither credit nor debit account facilities or balances with financial institutions. 
   Realizing these disadvantages in the deployment of reloadable micropayment reload devices the present invention provides such loading services in a completely offline environment thus reducing the capital necessary to deploy reload devices in adequate numbers to convenience the user. In addition to the added convenience the user will also have the ability to load non-fixed amounts if so desired. Such a reload device has the added benefit of enabling the issuing organization to grant refunds to their media using customers, saving the additional costs of mailing refund cheques to users who have substantiated refund claims further adding convenience to customers. 
   SUMMARY OF THE INVENTION 
   A method for a value supplier to transfer value to an electronic purse possessed by a holder without requiring direct electronic communication between said value supplier and said medium, said method comprising the steps of:
         (i) providing a portable storage medium to said holder having a Card Identification Code (“CIC”), a machine readable and reconfigurable Transaction Sequence Number (“TSN”) storage area and at least one said purse wherein each said purse is a machine readable and reconfigurable storage means and has a unique purse address;   (ii) recording said TSN against said CIC in a reconfigurable data storage and retrieval system;   (iii) receiving a request from said holder including said CIC, a desired value and payment instructions;   (iv) determining said TSN stored in said data storage and retrieval system against the CIC presented in step (iii);   (v) using an encryption algorithm to generate a unique One Time Number (“OTN”) based on said CIC, said TSN, said purse address and said desired value;   (vi) presenting said OTN to said user;   (vii) reconfiguring said TSN in said storage and retrieval system to vary said TSN by a predetermined increment;   (viii) providing a reload device having a reader for reading said TSN and CIC from said portable storage medium, CIC input means for receiving said CIC on said storage medium, OTN input means for receiving said OTN from said holder, a decrypter having a decryption algorithm corresponding to said encryption algorithm in step (v) for decrypting said OTN, a verifier for verifying that said CIC and TSN on said storage medium match said OTN input by said holder and a loader for loading value into said purse corresponding to said desired value;   (ix) receiving said storage medium in said reloader;   (x) determining said CIC and said TSN on said storage medium and receiving said desired value and said OTN;   (xi) decrypting said OTN using said decryption algorithm;   (xii) verifying whether said CIC and TSN components of said OTN conform to said CIC and said TSN on said storage medium;   (xiii) if said verifying in step (xii) determines conformance, loading said desired value into the purse identified by said purse address and incrementally adjusting said TSN on said storage medium by said predetermined increment in step (vii); and,   (xiv) if said verification in step (xii) fails to determine conformance, causing said reloader to display an error message.       

   The method may include the further steps of:
         (xv) configuring said reload device to monitor a predetermined number of retries of steps (ix) through (xii) for a given of said storage medium and, should said predetermined number of retries fail to yield a determination of said conformance, to enter a “disabled” indicator on said storage medium; and,   (xvi) further configuring said reload device to check for said disabled indicator and if detected, cease carrying on with the transaction steps and to display an error message to said holder.       

   The payment instructions received in step (iii) may include payment issuer information and may be confirmed with the issuer prior to continuing. Should payment be refused by the payment issuer the cardholder may be notified accordingly. 
   A reload device is provided for a portable value storage medium (“medium”). The reload device has a medium reader for reading a stored transaction sequence number (“TSN”) stored on the medium, a CIC input means for receiving a presented Card Identifier Code (“CIC”) and an OTN input means for receiving an One Time Number (“OTN”) containing encrypted TSN, CIC and value components and purse address. The reload device further has a decoder for decoding the OTN to determine the encrypted TSN, CIC and value components. The reload device also has a comparator communicating with the medium reader, CIC input means, OTN input means and decoder for comparing at least the encrypted TSN and CIC with the stored TSN and presented CIC. A loader communicates with the comparator for loading value onto the medium corresponding to the value. The comparator is configured to only load the value if the encrypted TSN and CIC components accord with the stored TSN and presented CIC. The reload device also has a TSN updater for updating the stored TSN to a next sequential TSN. 
   The reload device may have a security means associated with the reloader and the comparator. The security means may disable the medium upon detecting a predetermined number of unsuccessful OTN inputs against a particular CIC, causing an error message to be presented to a holder of the medium seeking to add value thereto. 
   A security means may, after the unsuccessful OTN inputs place a restriction on the card against further use. The medium reader may read any such restriction and notify the comparator to disable the storage medium without requiring any further unsuccessful attempts. 
   An OTN generator is provided for generating a One Time Number (“OTN”) for subsequent offline use with any of the issuing organization&#39;s loaders for loading a predetermined value onto a storage medium having a Card Identifier Code (“CIC”) and a reconfigurable stored Transaction Sequence Number (“TSN”). The OTN generator has a database for storage and retrieval of information on account status, CIC&#39;s for issued cards and the current TSN associated with each CIC. The OTN generator further has a system processor communicating with the database and access means associated with the processor for oral or written communication between a holder of the medium and the OTN generator. The OTN generator further has input means associated with the access means for receiving the CIC, a desired amount and type of value to be processed and a purse address. Debit means may be associated with a system processor for debiting the source of funds by an amount corresponding to the desired amount of value. Verification means may be associated with a system processor for determining whether the source of funds identified by the holder of the medium is in good standing. An encrypter may be associated with the system processor for generating the OTN according to an encryption algorithm based on at least the CIC, the TSN, the desired value and purse address. The processor may be configured to provide an error message if the account is not in good standing. The processor may be configured to signal the encrypter to generate a valid OTN and to communicate the valid OTN to the holder. The holder is thus able to input the OTN into the reloader for decryption and for the reloader to write a value onto the medium. The processor may further be configured to update the database to adjust the TSN associated with the CIC by a predetermined increment after generating a valid OTN. 
   The access means of the OTN generator may communicate over at least one of a computer and a telephone network. The input means of the OTN generator may be a telephone handset or a computer keyboard. The OTN generator output may be electronic via speech generator or written to a display screen or a document generator. 

   
     DESCRIPTION OF DRAWINGS 
     Preferred embodiments of the present invention are described below with reference to the accompanying illustrations in which: 
       FIG. 1  is a pictorial representation of a storage medium according to the present invention; 
       FIG. 2  is a perspective view illustrating a reload device according to the present invention; 
       FIG. 3  is a device functional block diagram of the reload device; 
       FIG. 4  is a device level transaction flow chart for the reload device; 
       FIGS. 5 and 6  are a flow chart in two parts illustrating a device level transaction flow algorithm in accordance with the present invention; 
       FIG. 7  is a flow chart illustrating a manner according to the present invention that an OTN may be provided to a holder; 
       FIG. 8  is a flow chart illustrating an alternative embodiment of a way that an OTN may be provided to a holder; 
       FIG. 9  is a block diagram illustrating OTN encryption elements; 
       FIG. 10  is a schematic illustration of an OTN generator in accordance with the present invention; and, 
       FIG. 11  is a flow chart illustrating a possible sequence of steps for resychronizing a TSN according to the present invention. 
   

   DESCRIPTION OF PREFERRED EMBODIMENTS 
   A storage medium according to the present invention is generally indicated by reference  20  in  FIG. 1 . The storage medium  20  may be a magnetic stripe card although other configurations, such as a microchip contained in a card, a key fob or other physical carrier may be utilized. 
   The storage medium  20  has a card identification code  22  (“CIC  22 ”) unique to that storage medium  20 . 
   The CIC  22  would generally be user readable as the users would be required to recite it as part of the transaction described below. 
   The storage medium  20  has an area  24  which is machine readable and reconfigurable on which is stored a Transaction Sequence Number (“TSN”). The storage medium further has at least one area referred to as a “purse”  26  which is a reconfigurable storage means to which value may be added and from which value may be removed. The purse  26  may be part of the area  24  or an adjunct thereto. Each purse  26  would have a unique address associated with it. The address would have to be accessed to load each purse  26 . 
   In use, the storage medium  20  may be issued to a holder (reference  208  in  FIG. 10 ) by a value supplier. The holder  208  can then contact the value supplier and, as discussed in more detail below, arrange to have value added to the purse  26 . The value is added using a reload device  50  in  FIG. 2 . The reload device and the value supplier in effect communicate via an encrypted code (i.e. the One Time Number (“OTN”)) using the holder  208  as an intermediary rather than through direct electronic communication. 
   The storage medium  20 , once loaded, may be utilized to transfer at least a portion of the value to a storage medium reader such as a vending machine, a washing or drying machine, a telephone, a transit system or other users where preferably cashless small transactions are required. As different users may have different purse requirements, more than one purse  26 , each satisfying different user requirements, may be provided. For example a transit pass may be configured in terms of “passes” with one pass required per ride rather than having a monetary value which is debited by a medium reader. The expression “value” should therefore be broadly interpreted to include other than actual cash values loaded. 
     FIG. 2  is a pictorial representation illustrating a reload device  50  according to the present invention.  FIG. 3  is a device functional block diagram of the reload device  50 . 
   The reload device  50  includes a medium reader  52  for reading information stored on the storage medium  20 , in particular the TSN on the area  24  and preferably also the purse  26 . 
   The reload device  50  further has a CIC input means such as the keypad  54  for receiving the CIC  22 . While a keypad  54  is illustrated, alternative means may be utilized. For example the CIC may be both printed on the card and stored on the card in machine readable form in which case the medium reader  52  may also be configured to act as the CIC input means. 
   The reload device  50  has an OTN input means for receiving the OTN. The OTN input means may be the keypad  54 . The OTN is an encrypted code based on the TSN, the CIC and value components. The OTN may also contain a purse identifier component such as a purse address. The OTN is in effect the message carried by the holder of the storage medium from the value supplier to the reload device  50  which enables verification of the storage medium  20  and loading of value into the purse  26 . 
   As the OTN is an encrypted message to the reload device  50 , the reload device  50  includes a decoder  55  which may be a reload processor  56  communicating with a first security module  58  which runs a decryption algorithm. The decoder  55  receives the OTN and determines the TSN, CIC and value components. 
   The reload device  50  also has a comparator for comparing the CIC and TSN input or read from the storage means  20  with the TSN and CIC determined by the decoder  55 . This may for example be accomplished by suitably configuring the reload processor  56  and having it communicate with the keypad  54 , medium reader  52  and first security module  58 . “Suitably configuring” refers to providing appropriate hardware and software either as part of or in communication with the reload processor  56 . 
   The comparator determines whether the information contained in the OTN accords with the TSN and CIC on the storage medium  20 . If it does, then the comparator instructs, such as through the reload processor  56 , a loader  60  to add the value to the appropriate purse  26 . If it doesn&#39;t then the comparator may simply refuse to instruct the loader  60  but more preferably will arrange for an error message to be presented to the holder of the storage means  20 . This may be accomplished by communicating the non-accord condition to the reload processor  56  which in turn instructs a display  64  also in communication therewith to display the error message. 
   The reload device  50  is also provided with a TSN updater for updating the TSN after each successful transaction. This may form part of the loader  60 . The TSN is updated for example by a predetermined increment or to a next predetermined sequential value after each successful transaction. This prevents the storage medium  20  from being loaded again using the same OTN. The reason it can&#39;t be loaded again is that the updated TSN will not accord with the encrypted TSN resulting in a non-accord determination by the comparator. 
   The reload device  50  may incorporate further security features for example a second security module  62  may communicate with the reload processor  56  to provide access codes enabling the reload processor  56  to communicate with the medium reader  52 , keypad  54  and possibly also the first security module  58 . 
   Additionally, the reload  50  processor  56  may be configured to monitor subsequent unsuccessful attempts to load value such as may be the case if someone is attempting to guess an OTN. The area  24  or any other area of the storage medium  20  which is machine readable may then be loaded with a “security lock-out” notation which can be detected by the medium reader  52  and communicated to the reload processor  56 . The reload processor may be further configured to disable the storage medium  20  and cause the display  64  to present a suitable error message. The restriction on reloading may be time limited. 
   Alternatively, once a security lock-out notation is placed on the storage medium  20 , the system can be configured to require entry of a one time “release” code to be provided by the value supplier in order to remove the security lock. 
   On occasion it may be necessary to resynchronize the TSN on the storage medium  20 . This might for example occur as a result of a system malfunction. Accordingly the reload processor  56 , decoder  55  and loader  60  may be configured to allow the keypad to present a coded TSN to the reload processor  56  for decoding by the decoder  55  and loading onto the storage medium  20  in lieu of any previously loaded TSN. 
     FIG. 4  is a device level transaction flowchart  100  for the reload device  50  illustrating user interaction with the device. Box  102  corresponds to the user inserting the storage medium  20  into the medium reader  52  and the medium reader  52  reading the storage medium  20 . Box  104  depicts the display  64  showing the balance on the card. Alternatively the display  64  could prompt for the OTN and also the CIC if the CIC isn&#39;t read by the medium reader  52 . Box  106  represents the user entering the OTN on the keypad  54 . 
   The reload device  50  next performs a validation algorithm at box  108  which is performed by the comparator. Should the validation result in failure as depicted by box  110 , an error message is displayed as depicted by box  112 . Should the validation prove successful, the display  64  may be instructed to display an approved load value as depicted by box  114 . 
   The reload processor  56  may also be configured to determine whether the approved reload amount will exceed a predetermined maximum balance in the selected purse  26 . This is depicted by box  116 . Should this occur, the display  64  may be caused to present such a message as depicted by box  110  and further prompt the holder to remove the storage medium  20  from the reload device  50 , as depicted by box  112 . 
   Should the selected purse  26  be capable of accepting the approved load value the reload processor  56  may instruct the display  64  to display the current balance (box  120 ) and instruct the loader  60  to load the approved value into the selected purse  26  as depicted by box  122 . The reload processor  56  may then calculate and cause the display  64  to present first the new balance (box  124 ) and finally cause the display  64  to display a message, such as at box  126 , informing the holder that the transaction is complete and prompting the holder to remove the storage means  20  from the reload device  50 . 
     FIGS. 5 and 6  are a flow chart in two parts illustrating a device level transaction flow algorithm  150  in accordance with the present invention. 
   At reference  152  the storage medium  20  is presented to the medium reader  52 . At reference  154  the display  64  shows any remaining balance on the card. The reload device next, at reference  156 , determines if any security lock-out is active on the card. If a security lock-out is active, then, at reference  158  the reload device  50 , typically through its reload processor  56  determines if the security lock-out has expired. If it has expired, then at reference  160 , it is erased, If it hasn&#39;t expired, then at reference  162  the display  64  is operated to present an appropriate message. This assumes that a time sensitive security lock-out is being used, which may not be the case. The system may be configured to require that a one time code be obtained from the value supplier in order to remove the security lock-out. 
   If a security lock-out is either not present or has expired the reload device  50  accepts a user entered OTN at reference  164 . The reload processor  56  extracts the TSN from the OTN at reference  166 . The comparator at  168  compares the decrypted TSN with the TSN read off of the storage medium  20  by the medium reader  52 . A failed match causes the display  64  to present an appropriate message at reference  170 . Next at reference  172 , the reload processor  56  determines whether a predetermined sequential retry threshold has been achieved. If not the storage medium may be reinserted at  152 . If it has been achieved then a security lock-out, which may be time sensitive, is placed on the storage medium  20  at reference  174 , at least temporarily disabling the storage medium  20  from operating the reload device  50 . 
   It will be appreciated that presence of a security lock-out disables the storage means  20  from being used with any reload device  50 . This is because the security lock-out is carried by the storage means  20  rather than by the reload device  50 . 
   If no security lock-out is currently active and the decrypted TSN matches the stored TSN, full decryption begins at referenced  176 . At reference  178  the comparator checks for a match between the CIC on the storage medium  20  and the CIC decrypted from the OTN. A failed match causes a return to step  170 . A successful match at reference  180  may result in the reload processor  56  determining which purse  26  to load if more than one purse  26  is available. This can be part of the information encrypted in the OTN. Next, at reference  184 , the reload processor  56  determines whether adding the approved value will exceed a maximum balance. If yes, then the display is operated to present a suitable message at reference  186  which may also prompt the holder to remove the storage medium  20  from the reload device  56 . 
   Should the approved load value not exceed the maximum card balance, the value is added and the TSN sequentially adjusted. Either may follow the other. According to the  FIG. 6  embodiment the TSN is incremented at reference  188  and the value loaded to the purse  26  by the loader  60  at reference  190 . Appropriate accompanying messages may also be displayed. For example at reference  192  the current balance and amount being loaded may be displayed. Next at reference  194  the new balance may be displayed. Generally at reference  196  the holder is instructed to remove the card and the reload transaction is completed at reference  198 . 
     FIGS. 7 and 8  are flow charts illustrative of two ways that an OTN may be provided to the holder.  FIG. 9  illustrates the OTN encryption elements.  FIG. 10  is a schematic illustration of an OTN generator  200  in accordance with the present invention. 
   The OTN generator  200  has a database means  202  for storage and retrieval of information on account status associated with each storage medium  20  that has been issued and may include information on account status of the holder  208  as well as any other relevant account. The database  202  may further provide for storage and retrieval of CIC&#39;s for issued storage medium  20  and current TSN&#39;s associated with each CIC. 
   The OTN generator  200  has a system processor  204  which communicates with the database  202 . Access means  206  are associated with the system processor to enable communication between a holder  208  of the storage medium  20  and the system processor  204 . The access means  206  has input means  210  which may be fully automated for example relying on a computer hook-up over the Internet or utilizing touch tone features of a telephone handset. Alternatively (or additionally) the access means  206  may have input means  210  which uses human intervention such as a call centre wherein the call recipient has keyboard access to the system processor. 
   The input means  210  may prompt for and receive the CIC and a desired amount of value from the holder  208 . As well the input means  210  may prompt for and receive a source of funds  212  selected by the holder  208  from where the value is to be obtained. The source of funds may for example be a credit facility or a bank account held by the holder  208 . The credit facility may be a credit card company or the value supplier that controls the OTN generator  200 . 
   Account verification means  214  may be associated with system processor  204  for determining whether the selected source of funds is in good standing. The account verification means may in turn communicate with the source of funds  212  or with the database  202  depending on whether current or historical data is to be verified. 
   Debit means  216  are associated with the system processor  204  for enabling the system processor  204  to debit the source of funds  212  by an amount corresponding to the desired value and possibly also a service or transaction charge. 
   An encrypter  218  is associated with the system processor  204  for generating the OTN according to an encryption algorithm. As discussed above, the encryption algorithm would typically be based on at the CIC, TSN and the desired amount of value. The encryption algorithm may also take into account which purse  26  is selected if more than one is available. 
   The system processor  204  may be configured to signal the encrypter to generate an OTN which will cause the reload device  50  to generate an error message if the account is not in good standing. Alternately the OTN may communicate an appropriate message to the holder  208  through the access means  206  should this be the case. 
   The system processor  204  may be further configured to signal the encrypter to generate a valid OTN and to communicate the OTN to the holder through the access means  206 . Output means  220  may be provided in communication with the system processor  204  to link the system processor  204  with the access means  206 . The input means  210  and output means  220  may be incorporated in a common element of the OTN generator  200 . 
   The system processor  204  is further configured to update the database to adjust the TSN associated with the CIC of the storage medium  20  to be loaded by a predetermined increment. The predetermined increment will be the same for the OTN generator  200  as for the reload device  50 . 
     FIG. 7  illustrates how an OTN may be generated with the OTN generator  200  in an automated telephone system configuration. At reference  300  the holder  208  calls an automated telephone number. The holder  208  may be prompted to and may choose a language preference at reference  302 . At reference  304  the holder  208  is prompted for and enters, using a telephone keypad, the CIC number. The holder  208  is then prompted for and enters a credit card number and expiry date at reference  306 . At reference  308  the holder  208  is prompted for and enters a desired load amount, and, if applicable, a selected purse  26 . 
   The system processor  204  verifies the availability of funds at reference  310  through the account verification means  214 . Should the verification fail, as indicated at reference  312 , the transaction is cancelled as indicated by reference  314 . 
   Should the verification be successfully approved, the system processor  204 , using the encrypter  218 , generates an OTN at reference  316 . The system processor further increments the TSN in the database  202  at  318  and provides the OTN to the holder at reference  320 . 
   It will be appreciated that the above sequence may be varied to some extent. For example the load amount and purse may be entered before the credit card information. Also the TSN may be incremented after the OTN is provided to the card holder  208 . 
     FIG. 8  is a flow chart illustrating the generation of an OTN using a call centre as the access means  206 . The holder  208  phones the call centre at reference  350  and provides, possibly upon prompting, the CIC at reference  352 . The holder  208  is further prompted for and provides a credit card number and expiry date at reference  354  and a desired load amount and purse  26  at reference  356 . The holder  208  would supply the foregoing information to a call centre operator who has input means  210  for inputting the information into the system processor  204 . 
   The system processor  204  may verify the transaction with the source of funds  212  at reference  358 . Although it is expected that in most cases the system processor  204  would be a computer, it may be possible to use a human operator as the system processor  204  as long as access is provided to the peripheral components of the OTN generator  200  which communicate with the system processor  204 . 
   Should verification result in a denial, as shown at reference  360 , the transaction is cancelled at reference  362  and the holder  208  may be informed accordingly. 
   Should verification prove successful and result in acceptance, the call centre at reference  364  enters the data into the system processor which at reference  366  runs the encrypter  218  to calculate the OTN. This may further require accessing the database  202  to obtain the current TSN. The call centre provides the OTN to the holder  208  at reference  370 , the TSN is incremented in the database  202  at reference  368  and the transaction is complete. 
     FIG. 9  is a schematic diagram illustrating one manner in which an OTN may be encrypted. Two encryptions are illustrated. In a first encryption  400 , elements of the CIC, approved load amount and desired purse are loaded at references  402 ,  404  and  406  respectively. The first encryption yields a first result  408 . A second encryption occurs at reference  410  and is based on the TSN which is loaded at  412 . The second encryption encrypts the TSN to yield encrypted TSN  414 . The encrypted TSN  414  is combined with the first result  408  to yield a resultant OTN  416  which is the OTN provided to the holder  208 . 
     FIG. 11  is a flow chart illustrating a possible sequence of steps for resychronizing a TSN when a load attempt fails. At reference  500 , the holder  208  calls a call centre to report a failed attempt. The call centre obtains the CIC and at reference  502  determines the TSN. The TSN may be encrypted at reference  504  for example using the encrypter  218  and the encrypted TSN is provided to the holder  208  at reference  506 . The user records the encrypted TSN at reference  508  and the call centre may, at reference  510  synchronize the database with the new TSN. 
   Reload devices  50  of the above type may be owned by different issuing organizations, each of which will have their own OTN generator  200 . Should this be the case, provision will be required to separate one organization&#39;s storage media  20  and reload devices  50  from those of another. This may be accomplished for example by having an organization identifier as part of the purse address. 
   The above description is intended in an illustrative rather than a restrictive sense. Variations may be apparent to those skilled in the art without departing from the spirit and scope of the invention as defined by the claims set out below. For example it may not be necessary to follow the exact sequence of steps described or to use the exact encryption methodology. Variations to these and other aspects will no doubt be apparent to those skilled in the relevant arts.