Patent Publication Number: US-6705517-B1

Title: Automated banking machine system and method

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit of U.S. Provisional Application Serial No. 60/285,724 filed on Apr. 23, 2001 and is a continuation-in-part of U.S. application Ser. No. 09/193,787 filed on Nov. 17, 1998 which is a continuation-in-part of International Application PCT/US97/21422 filed on Nov. 25, 1997 and which designated the U.S. (now U.S. application Ser. No. 09/077,337). The nonprovisional applications designated above, namely application Ser. No. 09/193,787 filed Nov. 17, 1998 and PCT/US97/21422 filed on Nov. 25, 1997 (now 09/077,337) claims the benefit of U.S. Provisional Application Nos.: 60/031,956 filed on Nov. 27, 1996; 60/091,887 filed on Jul. 7, 19918; 60/095,626 filed Aug. 7, 1998; and 60/098,907 filed Sep. 2, 1998. 
    
    
     TECHNICAL FIELD 
     This invention relates to automated banking machines. Specifically this invention relates to an automated banking machine system and method that is capable of configuring an automated banking machine with encryption keys. 
     BACKGROUND ART 
     Automated banking machines are well known. A common type of automated banking machine used by consumers is an automated teller machine (“ATM”). ATMs enable customers to carry out banking transactions. Common banking transactions that may be carried out with ATMs include the dispensing of cash, the making of deposits, the transfer of funds between accounts, the payment of bills and account balance inquiries. The types of banking transactions a customer can carry out are determined by capabilities of the particular banking machine and the programming of the institution operating the machine. Other types of automated banking machines may allow customers to charge against accounts or to transfer funds. Other types of automated banking machines may print or dispense items of value such as coupons, tickets, wagering slips, vouchers, checks, food stamps, money orders, scrip or traveler&#39;s checks. For purposes of this disclosure an ATM, an automated banking machine, or an automated transaction machine shall encompass any device which carries out transactions including transfers of value. 
     Many ATMs are configured to require consumers to enter a Personal Identification Number (PIN) with a keypad of the ATM prior to being granted permission to perform transaction functions with the ATM. The PIN is communicated to a host system by the ATM for purposes of authenticating the identity of the consumer. To prevent the PIN from being stolen by an unauthorized party, ATMs are operative to encrypt the PIN prior to sending the PIN to a host system. For many years Single-DES encryption has been used by ATMs to encrypt PINs using an 8 byte Communication (COM) secret key. Unfortunately, as the cost of computer processing power decreases over time, the risk of the encryption being cracked by unauthorized individuals or entities is increasing. Consequently, there exists a need for new and existing ATMs to include support for a more secure encryption protocol. 
     PIN information may be encrypted using a COM key known to both the ATM and the host system. The COM key may be securely sent to the ATM from the host system by encrypting the COM key with a terminal master key known to both the ATM and the host system. To maintain the secrecy of a terminal master key, when an ATM is being initially configured for operation, the initial terminal master key is often required to be manually installed by a two-person team at the ATM. Each person of the team has knowledge of only a portion of the information necessary to generate the initial terminal master key. To install the terminal master key successfully, each person must input into the ATM his or her known portion of the terminal master key. Once installed, the inputted portions undergo a mathematical procedure that results in a sixteen (16) character key unknown to either person. 
     In general, financial institutions or other entities which operate ATMs, are responsible for inserting a unique initial terminal master key in their ATMs. Such entities are also responsible for periodically updating the COM key used for PIN encryption. Although the use of two-person teams to install the initial terminal master key increases the security of the system, in general such a protocol increases the maintenance costs per ATM and is generally cumbersome to manage. As a result, existing keys on ATMs are often not updated on a regular basis, which increases their vulnerability to being cracked. Consequently, there exists a need for a new system and method of installing the initial terminal master key which is less costly and less cumbersome to perform. There is a further need for a new system and method of installing a terminal master key on an ATM which is equally or more secure than a two-person team system. 
     DISCLOSURE OF INVENTION 
     It is an object of an exemplary form of the present invention to provide an automated banking machine at which a user may conduct transactions. 
     It is a further object of an exemplary form of the present invention to provide an automated banking machine which is more secure. 
     It is a further object of an exemplary form of the present invention to provide an automated banking machine which supports more secure encryption protocols. 
     It is a further object of an exemplary form of the present invention to provide a system and method for securely installing a terminal master key on an automated banking machine. 
     It is a further object of an exemplary form of the present invention to provide a system and method for securely and remotely installing a terminal master key on an automated banking machine. 
     It is a further object of an exemplary form of the present invention to provide a system and method for securely and remotely installing a terminal master key on an automated banking machine with the use of only a single operator at the ATM. 
     Further objects of exemplary forms of the present invention will be made apparent in the following Best Modes for Carrying Out Invention and the appended claims. 
     The foregoing objects are accomplished in an exemplary embodiment by an automated banking machine that includes output devices such as a display screen, and input devices such as a touch screen and/or a keyboard. The ATM further includes devices such as a cash dispenser mechanism for sheets of currency, a printer mechanism, a card reader/writer, a depository mechanism and other transaction function devices that are used by the machine in carrying out banking transactions. In the exemplary embodiment the ATM includes at least one computer. The computer is in operative connection with the output devices and the input devices, as well as with the cash dispenser mechanism, card reader and other physical transaction function devices in the banking machine. The computer is further operative to communicate with a host system located remotely from the ATM. 
     In the exemplary embodiment, the computer includes software programs that are executable therein. The software programs of the ATM are operative to cause the computer to output user interface screens through a display device of the ATM. The user interface screens include consumer screens which provide a consumer with information for performing consumer operations such as banking functions with the ATM. The user interface screens further include service screens which provide a person servicing the ATM with information for performing service and maintenance operations with the ATM. In addition the ATM includes software programs operative in the computer for controlling and communicating with hardware devices of the ATM including the transaction function devices. 
     In an exemplary embodiment, the ATM includes encryption software and/or hardware which is operative to encrypt PIN information with DES keys securely received from the host system. In one exemplary embodiment, the ATM includes a keypad or encrypting pin pad (EPP) input device which is operative to encrypt a consumer entered PIN within a secure module directly at the keypad. The EPPs of exemplary embodiments are further operative to perform either Single-DES or Triple-DES encryption operations for message authentication, local PIN verification and key transport. 
     In the exemplary embodiment, the EPP and/or other hardware/software in the computer may be operative to establish a secure communication session between the ATM and a host system environment for transferring terminal master keys to the ATM from the host system. In the exemplary embodiment, individual authentication may be required from both the ATM and the host system to establish the secure communication session. Authentication may be achieved in one exemplary embodiment using digital certificates and digital signatures. Both the ATM and the host system each have individual certificates which may be exchanged between the ATM and host system in a point-to-point communication. The exchanged certificates enable the ATM and the host system to authenticate each other and establish a secure session through a Public Key Infrastructure (PKI). The secure session enables DES keys to be remotely installed and updated on an ATM by a host system. In the exemplary embodiment, the host system may be operative to coordinate the remote key management of DES keys for a plurality of ATMs connected to the host system. 
     To facilitate authentication and key management, both the ATM and host system may each include a pair of certificates. A first one of the certificates may be used for enciphering and deciphering information sent between the host system and the ATM. A second one of the certificates may be used for generating digital signatures and verifying digital signatures on information passed between the host system and ATM. In the exemplary embodiment, the ATM or a device of the ATM such as an encrypting keypad or encrypting pin pad (EPP) may be manufactured to include an initial set of the certificates which are issued by an initial certificate authority (CA). The exemplary ATM or a EPP device of the ATM may also be manufactured to include the public keys of the initial CA. In addition a host system connected to the ATM may include certificates issued by the initial CA and the public keys of the initial CA. 
     In the exemplary embodiment, an operator at the ATM may be enabled to cause the ATM to initiate the exchange of certificates between the ATM and the host system. To prevent a possible man-in-the-middle attack on the ATM and host, exemplary embodiments may include the ATM outputting through a display device of the ATM, a one-way hash of the public key of the host system found on each certificate of the host system. The operator may then independently verify that each displayed one-way hash corresponds to a hash of the expected public key found in an authentic certificate of the host system. 
     In an exemplary embodiment, a financial institution may be operative to replace the initial CA with a new CA and may be operative to remotely cause the ATM and the host system to receive new sets of certificates issued by the new CA. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is; a schematic view of an exemplary embodiment of an ATM system. 
     FIG. 2 is a schematic view of a further exemplary embodiment of an ATM system. 
     FIG. 3 is a schematic view of an exemplary embodiment of a system for remotely transferring terminal keys from a host system to an ATM. 
     FIG. 4 is a further schematic view of an exemplary embodiment of a system for remotely transferring terminal keys from a host system to an ATM. 
     FIG. 5 schematically represents an exemplary embodiment of a system and method for transferring a terminal master key from a host system to an ATM. 
     FIG. 6 schematically represents an exemplary embodiment of a system and method for transferring a terminal master key from a host system to an ATM. 
     FIG. 7 schematically represents an exemplary embodiment of a format for an unsolicited status message. 
     FIG. 8 schematically represents an exemplary embodiment of a format for a write command message. 
     FIG. 9 schematically represents an exemplary embodiment of a format for a solicited status message. 
     FIG. 10 schematically represents an exemplary embodiment of a format for an operational command message. 
     FIG. 11 schematically represents an exemplary embodiment of a system and method for installing certificates in an exemplary embodiment of an EPP. 
     FIG. 12 schematically represents an exemplary embodiment of a system for transferring certificates of a host system to an EPP. 
     FIG. 13 schematically represents an exemplary embodiment of a system for transferring certificates of an EPP to a host system. 
     FIG. 14 schematically represents an exemplary embodiment of a system for distributing new certificate for a new certificate authority to an EPP. 
     FIG. 15 schematically represents an exemplary embodiment of a system for updating original certificates of an EPP with new certificates of the EPP signed by a new certificate authority. 
    
    
     BEST MODES FOR CARRYING OUT INVENTION 
     Referring now to the drawings and particularly to FIG. 1, there is shown therein a network configuration schematically indicated  10 , which includes the automated banking machine apparatus and system of an exemplary embodiment. Network  10  includes a plurality of automated banking machines  12  which in the exemplary embodiment of the invention are ATMs. ATMs  12  are connected to a computer system of a host system schematically indicated  14 . Host system  14  includes a computer system that may be operated by the bank or other institution which has primary responsibility for the ATMs  12 . Host banking system  14  may be connected to the ATMs  12  through a network  16 . Network  16  may include a local or proprietary network or a public network such as the Internet which provides communication between the computer system  14  and the banking machines  12 . In one exemplary embodiment the messages are transmitted through the network  16  in the Transmission Control Protocol/Internet Protocol (“TCP/IP”) format. In addition, the messages sent through network  16  may be sent in an encrypted or unencrypted form depending on the nature of the system and the security needs of the home bank. 
     FIG. 2 shows a schematic view of the ATM  12  used in connection with an exemplary embodiment of the invention. ATM  12  may include a touch screen  30 . Touch screen  30  includes a display screen which serves as an output device for communication with a user of the machine. Touch screen  30 , because it is a touch screen, also serves as an input device for receiving input instructions from a user. Touch screen  30  may be connected through an interface  32  to a computer  34  which is preferably housed within the machine. Alternative exemplary embodiments of the invention may include other output devices such as audio speakers and/or other display screens which may or may not be integrated with input devices. Alternative exemplary embodiments may also include other input devices such as function keys and keyboards which may or may not be integrated with output devices. 
     Computer  34  may also be in connection with a plurality of transaction function devices  36  which are included in ATM  12 . Devices  36  may include for example, a card reader/writer mechanism  38  and a keypad  40 . Devices  36  may further include a cash dispenser mechanism  42  which is operative to dispense sheets, which in some embodiments of the invention are currency or bank notes. Exemplary devices  36  may also include a depository  44  for accepting deposits into a secure location in the machine. A receipt printer  46  for providing transaction receipts to customers may also be included among devices  36 . A journal printer  48  may also be included among the devices for keeping a hard copy record of transaction information. In other exemplary embodiments other or additional transaction function devices which carry out other transaction functions may be used. Other exemplary embodiments may include fewer transaction function devices. It should be further understood that while the described exemplary embodiment of the invention is an automated banking machine, the principles of the invention may be employed in many types of transaction machines that do not necessarily carry out banking transactions. 
     Each of the devices may be operatively connected to an internal control bus  50  within the banking machine  12 . The control bus  50  outputs the internal messages to the particular devices. Each device may have an appropriate hardware interface which enables the particular device to operate to carry out its respective function in response to the messages transmitted to it on control bus  50 . Card reader/writer  38  may have a hardware interface schematically shown as  52 . Hardware interfaces  54 ,  56 ,  58 ,  60  and  62  may be respectively operative to connect key pad  40 , cash dispenser mechanism  42 , depository mechanism  44 , receipt printer mechanism  46  and journal printer mechanism  48  to the control bus  50 . 
     Computer  34  may have several software programs that are executable therein. In an exemplary embodiment these software programs may include a device interfacing software portion generally indicated  64 . Device interfacing software portion  64  may include a software device interface  66  that communicates electronic messages with the control bus  50 . The device interface software portion  64  may also include a device manager  68 . The device manager may be operative to manage the various, devices  36  and to control their various states so as to be assured that they properly operate in sequence. In an exemplary embodiment, the device manager may also operative to coordinate device objects in the software so as to enable operation of the devices by at least one object-oriented program  70 . The object oriented program portion  70 , for example may include an application written in the JAVA® language by Sun Microsystems or an application designed to operator according to Microsoft&#39;s Net platform. Program  70  may work in conjunction with the device manager to receive object-oriented JAVA® or .NET messages which cause the devices to operate, and to transmit device operation messages indicative of a manner in which devices are operating and/or are receiving input data. 
     The device interfacing software portion  64  in the described exemplary embodiment may operate on computer  34  and may communicate through a physical TCP/IP connection  72  with the network  16 . The physical connection may be analog dial-up, serial port, DSL, ISDN connection or other suitable network connection. In the configuration of the system as shown, device interfacing software portion  64  may communicate at the IP address of computer  34  and at an IP port or socket indicated  74  that is different from the other software applications. In other embodiments of the invention, device interfacing software portion  64  may operate in a different computer than the other software applications of the invention. 
     In further exemplary embodiments, the device interfacing portion  64  may also be based on an open standard platform such WOSA/XFS (Windows Open Services Architecture/eXtensions for Financial Services) or J/XFS (Java/eXtensions for Financial Services). Such platforms include an open XFS manager which provides a uniform API for communication with the devices  36 . When using an XFS manager, the device interfacing portion may communicate with the hardware interfaces  52 ,  54 ,  56 ,  58 ,  60  and  62  through software components such as service provider (SP) interfaces supplied by the vendors of the devices  36 . 
     It should further be understood that although in this described exemplary embodiment the device interfacing portion  64  may be software, in other embodiments of the invention all or portions of the instruction steps executed by software portion  64  may be resident in firmware or in other program media in connection with one or more computers, which are operative to communicate with devices  36 . For purposes of the invention all such forms of executable instructions shall be referred to as software. 
     Other software may also operate in computer  34 . This software may include interface applications  75  which are operative to output interface screens through the output device  30  which provide information and instructions to consumers and/or operators for operating the ATM  12 . In one exemplary embodiment the interface applications may include software for handling mark up language documents. In the exemplary embodiment the interface applications may include HyperText Markup Language (HTML) document processing software such as a browser, schematically indicated  76 . In this described exemplary embodiment of the invention, the HTML document handling software includes a browser provided by Netscape®. However, in other embodiments other HTML document handling and communicating software and is browser software, such as Internet Explorer™ from Microsoft, may be used. It should be understood that in some exemplary embodiments browsers which process markup language documents to provide visible and/or audible outputs as well as other outputs, as well as browsers which do not provide human perceivable outputs, may be used. Browser  76  may communicate in computer  34  at an IP port indicated by  78 . 
     In an exemplary embodiment, the browser  76  may be in operative connection with JAVA® environment software  80  which enables computer  34  to run JAVA® language programs. However, other exemplary embodiments may use different types of software programs including Microsoft .NET applications and proprietary and platform specific terminal control software. 
     The JAVA® environment software  80  enables computer  34  to execute instructions in JAVA® script, schematically indicated  82 . The instructions that are executed by the computer in JAVA® script may be embedded JAVA® script commands that are included in the HTML documents or other markup language documents which are received through the browser  76 . The browser  76  in connection with the JAVA® environment software  80  which executes instructions in the embedded JAVA® script  82 , serve as an HTML document handling software portion for transmitting and receiving HTML documents and TCP/IP messages through the IP port indicated by  78 . 
     Computer  34  may also have executable software therein having a device application portion  84 . The device application portion  84  may contain executable instructions related to operation of the devices  36 . In one exemplary embodiment of the invention, the device application portion may include a plurality of JAVA® applets. In the described embodiment the applets include programs operable to control and keep track of the status of the devices with which they are associated. Certain applets may be operable to configure the browser to communicate messages. Certain applets may manage security and authenticate entities that use an the ATM. It should be understood that this approach is exemplary and in other embodiments other approaches may be used. For example, other embodiments may use .Net components and objects rather than or in addition to JAVA® applets. 
     In the described form of the invention, JAVA® applets may be associated with functions such as enabling the card reader mechanism, notifying the browser when a user&#39;s card data has been entered, operating the receipt printer mechanism, operating the journal printer mechanism, enabling the customer keyboard and receiving data input through the keyboard, operating the sheet dispenser mechanism, operating the depository, navigating to document addresses, timing device functions, verifying digital signatures, handling encryption of messages, controlling the mix of bills dispensed from multiple cash dispenser mechanisms, calculating foreign exchange, and ending a transaction and instructing the browser to return to communication with a server. Of course, in other embodiments, other applets or components may be used to control devices and use data to carry out various desired functions with the machine. The device application portion  84  may communicate in the computer  34  at an IP port indicated  86 . 
     In the described embodiment of the invention, the device application portion  84  of the software may not communicate its messages directly to the device interfacing software portion  64 . However, it should be understood that some embodiments of the invention may provide for the device application portion  84  to directly communicate device operation messages to the device program  70 . This may be done either internally using TCP/IP, by delivery of messages in a conventional manner through a queue established in the operating system of the computer that is associated with the software that interfaces with the devices, or by direct call to this software. 
     FIG. 3 shows an exemplary embodiment of the ATM  12  in communication through the network  16  with a financial transaction processing system which in this example includes the host system  14 . Host system  14  includes at least one server computer and may be operative to keep track of debiting or crediting customers&#39; accounts when they conduct transactions at the automated banking machines. In addition host system  14  may be operative to track transactions for purposes of accomplishing settlements with other institutions who are participants in the system and whose customers conduct transactions at the ATMs  12 . In an exemplary embodiment the host system  14  may be operative to communicate messages to the ATM  12  through network  16  using a secure socket connection (“SSC”) so as to minimize the risk of interception of the messages. Of course other techniques, including encryption message techniques, may be used to minimize the risk of interception of the messages. It should be understood that the make of ATM  12  is exemplary and other types of ATMs may be used with exemplary embodiments. 
     In the exemplary embodiment messages sent to the ATM  12  may include the instructions and information for the ATM to verify that the messages it receives are genuine. This may include digital signatures which when transferred using public key or private key encryption techniques verify the messages as genuine. The machine checks to be sure the signature in the messages received from the host system or another system corresponds to the digital signature for that address stored in memory, and enables operation with the transaction devices, such as the cash dispenser  42 , or the keypad  40  only when such correspondence is present. Of course various approaches to verifying and encrypting messages may be used in various embodiments. As used herein signatures or signed records encompass any indicia which is included in or is derivable from a record, such as a message or document which is indicative that it is authorized. 
     When performing transactions for a consumer, an exemplary embodiment of the interface application  75  may be operative to prompt a consumer to input his/her Personal Identification Number (PIN) using an input device such as keypad  40  of the ATM  12 . The exemplary embodiment of the ATM  12  includes encryption software and/or hardware which is operative to encrypt PIN information with a Communication (COM) secret key and a corresponding encryption algorithm and protocol. Examples of encryption algorithms and protocols which an exemplary embodiment may use to encrypt PIN information include symmetric cryptography algorithms such as Single-DES encryption and double-length key Triple-DES encryption. In other alternative exemplary embodiments, other symmetric or asymmetric cryptography algorithms and protocols may be used. 
     When the exemplary embodiment of the ATM  12  is initially configured to perform transactions with the host system  14 , a communication (COM) key  100  may be securely sent from the host system  14  to the ATM  12  through the network  16 . To prevent the COM key  100  from being stolen by an unauthorized third party, the COM key may be encrypted with a terminal master key  102  known to both the host system and the ATM. In the exemplary embodiment the terminal master key  102  may be a DES secret key, however in alternative exemplary embodiments the terminal master key may correspond to the one or more encryption keys for use with other symmetric or asymmetric encryption algorithms and protocols. 
     As discussed previously, a current practice for installing the terminal master key on an ATM includes having a two-person team manually input two different key components which are used by the ATM to construct the terminal master key. The described exemplary embodiment may be operative to install the terminal master key on an ATM remotely from the host system without the use of a two-person team. 
     FIG. 4 shows a schematic view of an exemplary embodiment of an ATM  200 . ATM  200  includes a keypad  202 . The keypad  202  includes an EPP  204  which may be operative to perform the encryption of inputs through the keypad and the encryption/decryption of information being sent in messages between the ATM and a host system. For example in exemplary embodiments, the EPP may be operative to encrypt an input such as an inputted PIN using the COM key  206 . The EPP  204  of the exemplary embodiment may further be operative to perform steps necessary to securely acquire the COM key  206  from the host system  210  using a terminal master key  208 . In addition, the exemplary embodiment of the EPP  204  may be operative to perform steps necessary to securely acquire the terminal master key  208  from the host system  210 . 
     To securely transfer the terminal master key  208  from the host system  210  to the ATM  200 , the exemplary ATM  200  is operatively programmed to cause the EPP  204  to establish a secure communication session, socket, and/or channel  214  between the ATM  200  and the host system  210  that may be used to securely transfer the terminal master key  208  through a network  222 . The exemplary ATM  200  may include a service software application  212 . The service software application  212  may be operative responsive to commands inputted into the ATM  200  by a single operator to cause the ATM  200  to establish the secure communication session  214  for securely transferring the terminal master key  208  to the EPP  204 . 
     In the exemplary embodiment, individual authentication may be required from both the ATM  200  and the host system  210 . Authentication may be achieved in one exemplary embodiment using certificates and a Public Key Infrastructure generally indicated  201 . In this described exemplary embodiment, both the ATM  200  and the host system  210  each are associated with their own digital certificates  218 ,  220 . The secure communication session  214  may be initiated by exchanging the certificates  218  of the host and the certificates of the ATM  220  between the ATM  200  and the host system  210 . In one exemplary embodiment, the certificates  218 ,  22 . 0  may be authenticated by both the ATM  200  and the host system  210  using a public key  232  of a trusted certificate authority (CA)  230 . 
     Once the certificates  218 ,  220  have been exchanged and authenticated, the exemplary embodiment of the ATM and host system may pass encrypted and digitally signed information between them. Such information for example may include signed messages, encrypted secret keys, updated CA public keys, and updated certificates. As shown in FIG. 4 the exemplary ATM  200  and host system  210  may be further operative to use the exemplary PKI system  201  to securely transfer the terminal master key  208  to the ATM  200 . This may be achieved in one exemplary embodiment by having the host system  210  encrypt the terminal master key  208  using a public key associated with at least one certificate  220  of the ATM. The host system  210  may then send a digitally signed message to the ATM  200  which includes the encrypted terminal master key  216 . In the exemplary embodiment, the ATM  200  may be operative to decrypt the encrypted terminal master key  216  using a corresponding private key of the ATM  200 . In addition the ATM  200  may be operative to authenticate the digital signature of the host system using a public key from one the certificates  218  of the host system. Using this described exemplary process, an exemplary host system may be operative in accordance with its programming to coordinate the remote key management of terminal master keys for a plurality of ATMs  200  connected to the host system. 
     When certificates are initially exchanged between the ATM  200  and the host system  210 , there exists a possibility that an unauthorized entity may perform a man-in-the-middle hacking attack to uncover information being passed between the ATM and host system. During such an attack the unauthorized entity may simultaneously impersonate both the ATM and the host system by exchanging imposter messages for the original messages being transferred between the ATM and host system. To reduce the risk of this type of attack, the service software application  212  may be operatively programmed to cause the ATM  200  to display through a display device, a one-way hash or digest of the public key of the host system found on the certificate  218  of the host system. The exemplary one-way hash of the public key of the host system may be calculated by the exemplary ATM  200  using a one-way hash function such as RD5 or SHA-1. The operator may then independently verify that the displayed one-way hash is identical to a one-way hash of the public key of the host system known by the operator to correspond to an authentic certificate of the host system. 
     In the exemplary embodiment, to facilitate both authentication and key management, the host system  210  may include two certificates  218  and the ATM  200  may include two certificates  220 . A first one of the certificates may be associated with a first set of private/public key pairs which are used for encrypting and deciphering the terminal master key and other information sent between the host system and the ATM. A second one of the certificates may be associated with a second set of private/public key pairs used for signing and verifying digital signatures on information passed between the host system and the ATM. In the exemplary embodiment, the EPP  204  of the ATM  200  may be manufactured to include the initial set of certificates  220  of the ATM stored therein. Such certificates  220  of the ATM which may be stored in a memory of the EPP  204  are issued by the CA  230 . The certificates  218  of the host system may also be issued by the CA  230 . However, it is to be understood that in alternative exemplary embodiments the certificates  218 ,  220  may be issued by different certificate authorities. 
     In the exemplary embodiment, the EPP  204  may include the necessary processing capabilities and programming to validate/authenticate the certificates  218  received from the host system  210  by validating/authenticating the digital signature of the CA  230  found on the certificates  218  of host system  210 . In the exemplary embodiment, the EPP  204  may be manufactured to include the public keys  232  of the CA  230 . The public keys  232  of the CA may be used by the EPP  204  to validate/authenticate the digital-signatures of the CA found on the certificates of the host  218 . Likewise, the host system  210  may be operative to validate/authenticate the certificates  220  of the ATM using the public keys  232  of the CA. 
     In exemplary embodiments, the terminal master key may be transferred between the host and an ATM using a remote key transport process based on protocols such as the key transport mechanism of ISID/IEC 11770-3 and the three-pass authentication mechanism of ISO/IEC 9798-3. These protocols may be used to transfer two shared secret keys in three passes and provide mutual entity authentication and key confirmation. 
     In exemplary embodiments, the EPP may be constructed so as prevent the secret encryption keys stored therein from being retrieved from the EPP by an unauthorized user, entity, software program, hardware device, or other probing or sniffing device. Exemplary embodiments of the EPP may further be operative to destroy and/or delete the secret keys from the memory of the EPP in response to the EPP being tampered with. For example, an exemplary embodiment of the EPP may destroy all or portions of the EPP memory in response to the packaging or outer enclosure of the EPP being opened or altered. 
     FIG. 5 shows a schematic view of system and method by which a single operator at an ATM  302  may initiate the process of transferring a terminal master key to the ATM  302  from the host system  304 . This method comprises a plurality of messages  306 ,  308 ,  350  being sent between the ATM and the host system which establish a secure communication session, socket, and/or channel  300  between the host system  304  and the ATM  302  which is used to transfer the terminal master key across a network. In this exemplary embodiment, a modified key transport mechanism may be employed which is based on the ISO/IEC 11770-3 and ISO/IEC 9798-3 protocols and which provides unilateral key transport from the host system to the ATM. In this described exemplary embodiment, ATM  302  may enable a single operator to input a command through an input device of the ATM which causes the ATM to initiate the remote transfer of a terminal master key to the ATM. In exemplary embodiments the key transfer may also be initiated by the host system. 
     In the exemplary embodiment, the ATM  302  and/or an EPP  303  of the ATM may generate a random number (R-ATM) in response to receiving the input from the operator. The random number (R-ATM) may be sent by the ATM  302  to the host system  304  as part of at least one message  306  which may include for example an unsolicited status message or other types of messages capable of being sent by an ATM to a host system. In this described exemplary embodiment, certificates of the ATM and the host system may have been previously exchanged with each other as will be discussed below. However, in an alternative exemplary embodiment, if certificates of the ATM have not yet been exchanged with the host system, the exemplary ATM  302  may be operative to include a certificate  320  associated with encipherment/decipherment of the ATM/EPP and a certificate  326  associated with signature/verification  326  of the ATM/EPP with the message  306  at this time. 
     FIG. 7 shows an example format for the unsolicited status message in a Diebold 91X ATM message protocol environment that may be used for message  306 . Here the random number (R-ATM) may be stored in the buffer data field  307  of the unsolicited status message. The status field  305  may include data which indicates that the unsolicited status message corresponds to a request to initiate the process of transferring the terminal master key. 
     In response to receiving the message  306  from the ATM, the exemplary host system may be operative to generate and return to the ATM at least one message  308  including for example a write command message or other types of message that an ATM is capable of receiving from a host system. The message  308  from the host system includes a terminal master key (TK) encrypted within an Encipherment Key Block (EKB). In the exemplary embodiment, the host system may generate the Encipherment Key Block (EKB) by encrypting the terminal master key (TK) and identifying data associated with the host system such as a host distinguishing identifier (I-Host) using a public encipherment transformation associated with the ATM and/or EPP of the ATM. The host distinguishing identifier (I-Host) may correspond to a unique number, name or other indicia which is associated with the host  304 . In the exemplary embodiment the public encipherment transformation associated with the ATM/EPP may include encrypting the information (TK and I-Host) using an encipherment public key  322  associated with the encryption/decryption certificate  320  of the ATM/EPP 
     In addition to sending the encrypted terminal master key (TK) and host distinguishing identifier (I-Host), the host system may be operative to send as part of the message  308  a random number generated by the host (R-Host), the random number received from the ATM (R-ATM), and identifying data associated with the ATM such as an ATM distinguishing identifier (I-ATM). The ATM distinguishing identifier corresponds to a unique number, name or other indicia associated with the ATM  302  or the EPP  303  of the ATM. 
     In the exemplary embodiment, the message data  309  corresponding to the random A number generated by the host system (R-Host), the random number received from the ATM (R-ATM), the ATM distinguishing identifier (I-ATM), and the Encipherment Key Block (EKB) may be digitally signed by the host system  304  to form a digital signature  310  using a private signature transformation associated with the host system. In the exemplary embodiment the private signature transformation associated with the host system may include signing the message using a signature private key  342  of the host system. 
     The resulting signed message  311  may use the PKCS # 7 : Cryptographic Message Syntax Standard format. The message syntax may use Abstract Syntax Notation One (ASN. 1 ) with Basic Encoding Rules (BER) and Distinguished Encoding Rules (DER). In exemplary embodiments where the message of the host system is being transmitted over a 7-bit ASCII network such in a Diebold 91X ATM message protocol environment, the binary output of the Abstract Syntax Notation One (ASN. 1 ) may be converted to 7-bit ASCII for transmission within the write command message. In an exemplary embodiment an encoding algorithm such as Base64 encoding may be used by the host system which is operative to convert octets (bytes) into printable ASCII characters. In other exemplary embodiments other encoding algorithms may be used which are operative to produce 7-bit ASCII from binary. 
     FIG. 8 shows an exemplary format for a write command message in a Diebold 91X ATM message protocol environment that may be used to transfer the information described as being included in the message  308  being sent to the ATM. Here the write command message  308  corresponds to a 91X Write Command VII message. The key change field  370  of the Write Command VII message may include data which indicates that the write command message corresponds to the remote transfer of a terminal master key. The encrypted and signed message data  311  which includes the terminal master key may be included in the new key data field  372  of the Write Command VII message. Referring back to FIG. 5, in an alternative exemplary or embodiment, if certificates of the host system have not yet been exchanged with the ATM, the exemplary host system  304  may be operative to attach certificates  332 ,  338  of the host system to the message  308 . 
     Once the message  308  is received by the ATM, the ATM and/or the EPP of the ATM may be operative to validate the digital signature  310  of the host system using the public verification transformation associated with the host system. In the exemplary embodiment the public verification transformation associated with the host may include validating the digital signature using a verification public key  340  associated with the signature/verification certificate  338  of the host. A positive validation of the digital signature may indicate that the message  308  from the ATM has not been tampered with prior to being received by the ATM  302 . Also a positive validation of the digital signature may indicate that the information in the message  308  originates from the host system and not a third party hacker. 
     After validating the digital signature  310 , the ATM and/or the EPP of the ATM may be operative to verify that the ATM distinguishing identifier data (I-ATM) in the message  308  corresponds to the identity of the ATM  302  and that the random number (R-ATM) in the message  308  corresponds to the original random number (R-ATM) sent to the host system in the message  306 . In addition to these validations, the exemplary ATM  302  and/or an EPP  303  of the ATM may be operative to decrypt the Enciphered Key Block (EKB) using the private decipherment transformation associated with the ATM/EPP. In the exemplary embodiment the private decipherment transformation associated with the ATM/EPP includes decrypting the information (TK and I-Host) using a decipherment private key  324  stored in the memory of the EPP. 
     Decrypting the Enciphered Key Block (EKB) produces the terminal master key (TK) and the host distinguishing identifier (I-Host). If the decrypted host distinguishing identifier (I-Host) corresponds to the correct host system, the ATM  302  and/or the EPP of the ATM may be operative to accept the terminal master key (TK). In the exemplary embodiment, if the ATM and/or EPP of the ATM has been previously set to use a single-length key such as Single-DES encryption and the new terminal master key (TK) correspond to a double length key, the ATM and/or the EPP of the ATM may be operative to automatically switch to an algorithm which use double-length keys such as double-length key Triple-DES encryption. In addition if the ATM and/or EPP of the ATM has been previously set to use double-length keys and the new terminal master key (TK) correspond to a single length key, the ATM and/or EPP of the ATM may be operative to automatically switch to an algorithm which use single length keys such as Single-DES encryption. 
     As shown in FIG. 5, the exemplary embodiment of the ATM  302  may be operative to confirm the acceptance of the terminal master key (TK) by sending to the host system  304  at least one message  350  including for example a solicited status message or other types of messages capable of being sent by an ATM to a host system. In this described exemplary embodiment, the message data  349  transferred within the message  350  may include the random numbers (R-ATM, R-Host) and the host distinguishing identifier (I-Host). The message data  349  may be further signed by the ATM and/or the EPP of the ATM using a private signature transformation associated with the ATM/EPP. In the exemplary embodiment the private signature transformation associated with the ATM/EPP may include signing the message using a signature private key  330  stored in the memory of the EPP. 
     The resulting signed message data  351  may use the PKCS # 7 : Cryptographic Message Syntax Standard format. As discussed previously, this message syntax may use the Abstract Syntax Notation One (ASN. 1 ) with Basic Encoding Rules (BER) and Distinguished Encoding Rules (DER) which is converted from octet (byte) strings to 7-bit ASCII using Base64 encoding. FIG. 9 shows an exemplary format for a solicited status message in a Diebold 91X ATM message protocol environment which may be used to transfer information corresponding to the described message  350 . Here the solicited status message may include the signed message data  351  within a buffer data field  382 . 
     In alternative exemplary embodiments, the message  350  may further include a cryptographic check value (CTK) for the terminal master key (TK). The cryptographic check value (CTK) may be generated with the ATM and/or the EPP of the ATM by encrypting the received Terminal Master Key (TK) with a verification number or a random number (text 2 ) using a public encipherment transformation associated with the host system. In the exemplary embodiment the public encipherment transformation includes encrypting the information (TK, text 2 ) using an encipherment public key  334  associated with the encryption/decryption certificate  332  of the host system. In this described alternative embodiment, the random number (text 2 ) may originally have been generated by the host system  304  and sent to the ATM  302  in the Enciphered Key Block (EKB) of the message  308  from the host system. 
     After receiving the message  350  from the ATM, the host system  304  may be operative to verify the digital signature  352  using the public verification transformation associated with the ATM/EPP. In the exemplary embodiment the public verification transformation associated with the ATM/EPP may include verifying the digital signature  352  using a verification public key  328  associated with the signature/verification certificate  326  of the ATM/EPP. Once the digital signature  352  is verified, the host system  304  may be operative to verify that the distinguishing identifier (I-Host) and the random numbers (R-ATM and R-Host) agree with the corresponding values sent by the host system in the message  308 . In the event that any one of the verifications performed by the ATM/EPP and host system fail, the exemplary ATM/ EPP and host system may be operative to destroy the terminal master key (TK). Also in the exemplary embodiment, each time this exemplary protocol is executed, a new terminal master key (TK) may be generated. 
     In alternative embodiments, where the message  350  from the ATM includes a cryptographic check valve (CTK), the exemplary embodiment of the host system  304  may be operative to decrypt the cryptographic check value (CTK) using a private decipherment transformation associated with the host system. In the exemplary embodiment the private decipherment transformation may include decrypting the cryptographic check value (CTK) using the decipherment private key  336  of the host system. The resulting decrypted terminal master key (TK) and verification number (text 2 ) may then be verified with the original values sent in the message  308  to further verify the integrity of the secure session  300 . 
     In addition to enabling a single operator at an ATM to initiate the remote transfer of a terminal master key to an ATM, an exemplary embodiment of the present system may further include a transfer of the terminal master key which is initiated by the host system. FIG. 6 shows a schematic view of an exemplary embodiment where the host system  304  may be operative to initiate the transfer of the terminal master key by sending to the ATM  302  at least one message  360  including for example an operational command message or other types of messages an ATM is capable of receiving from a host system. FIG. 10 shows an example of the operational command message for a Diebold 91X ATM message protocol environment that may be used to transfer information corresponding to the described message  360 . Here, the operational command message may include a command code field  363  which includes data representative of a command to initiate the remote transfer of terminal key. 
     Referring back to FIG. 6, the ATM  632  may respond to receiving the message  360 , by sending to the host system one or messages  362  including for example a solicited status message or other messages which an ATM is capable of sending to a host system. The messages  362  may contain the previously described random number (R-ATM). In a Diebold 91X ATM message protocol environment, for example, the data corresponding to the random number (R-ATM) may be included in a buffer data field of the solicited status message. After the host system  304  has received the message  362  with the random number (R-ATM), the messages  308 ,  350  may be transferred between the host system and ATM as previously described. 
     In this described exemplary embodiment the encipherment and decipherment transformations may be performed using public and private key pair sets and an asymmetric cryptography algorithm such as the RSA cryptography algorithm. In addition, the signature and verification transformations may be performed using a second set of public and private key pair sets and the RSA cryptography algorithm and a one-way hash function such as MD 5  or SHA-1. The RSA modulus for this exemplary embodiment may be 2048 bits. In alternative exemplary embodiments, other encryption and signature protocols and algorithms may be used including DSA, and AES (Rijndael). Also in this described exemplary embodiment, cryptographic calculations of the ATM may be performed by a processor in the EPP  303  of the ATM  302 . However, in other exemplary embodiments of the ATM, all or portions of the cryptographic calculations may be performed by other hardware devices, and computer processors of the ATM. 
     As discussed previously, many ATMs require a two-person team to install a terminal master key. The exemplary embodiment includes upgrading such ATMs to support receiving a terminal master key from a host system. In one exemplary embodiment, this upgrade may be performed by accesing the interior portion of an ATM and removing an existing EPP or other device designed to receive and/or hold a terminal master key constructed from two values manually inputted into the ATM by a two-person team. Once the existing EPP has been removed, an alternate EPP may be installed in its place. The alternate EPP may be operative to receive the terminal master key from the host system according to the previously described protocols. In this described embodiment the alternate EPP is operative to perform encryption, decryption, signature, and verification functions with the public and private keys of the EPP and the public keys associated with the host system and certificate authority stored in the EPP. In one exemplary embodiment, the alternate EPP may further be operative to encrypt inputted PIN values using either single-DES or triple-DES algorithms and protocols. 
     In an exemplary embodiment, the EPP may be manufactured to include the certificate associated with encipherment/decipherment  320  and the certificate associated with signature/verification  326  stored therein. In this described exemplary embodiment these certificates may be issued by an initial CA and are digitally signed using a primary private key of the initial CA. The certificates  332 ,  338  of the host system are likewise issued and signed by the initial CA. 
     In a further exemplary embodiment, the EPP may be manufactured to include a secondary set of the certificates  320  and  326  signed with a secondary private key of the initial CA. The secondary set of certificates is intended to be used as a backup, in the event that the secrecy of the primary private key of the initial CA is compromised. In such cases, the primary set of certificates may be revoked and the secondary set of certificates may be used in their place to sign/verify mess:ages and encipher/decipher messages at the EPP and host system. The revocation of the primary certificates may be initiated by the host system. The host system may send to the ATMs a secondary set of certificates of the host system signed with the secondary private key of the initial CA. When the exemplary EPP receives a secondary set of certificates from the host system, the EPP may be operative to return its secondary certificates to the host system. In alternative exemplary embodiments, the EPP and host system may initially exchange both primary and secondary sets of certificates. When it is necessary to revoke the primary set of certificates issued by the initial CA, the host system may send a message to each ATM which is representative of a command to stop using the primary certificates and to begin using the secondary certificates. 
     In addition to storing its own primary and secondary sets of certificates, the exemplary EPP may further be operative to store the primary and secondary public keys of the initial CA. These primary and secondary public keys of the initial CA may be included on respective primary and secondary certificates of the initial CA. The primary and secondary certificates of the CA may be self signed. 
     FIG. 11 shows a schematic view of an exemplary process  400  that may be used in one exemplary embodiment to configure an EPP  404  with certificates generated by the initial CA  402 . Here, the exemplary EPP  404  includes a processor  420 , a memory  422  in operative connection with the processor, and a hardware interface  424  in operative connection with the processor. The exemplary processor  420  of the EPP  404  may be operative to communicate with external devices and servers such as a host system, a processor of an ATM, or the initial CA through the hardwire interface  424 . When the EPP is initially manufactured and/or is re-commissioned, the hardware interface  424  may be connected to a system that is capable of sending messages between the EPP and the initial CA  402 . The system for initializing the EPP may include communication hardware, software and a network connection that is in communication with the initial CA and is operative to transfer messages between the EPP and the initial CA. In alternative exemplary embodiments, a system for initializing the EPP may include an ATM and host system that is in operative communication with the initial CA. The hardware interface of the EPP may be operative to communicate with the initial CA through the network interface of the ATM after being installed in the ATM. 
     When the exemplary EPP  404  is initially powered up, the processor  420  may be operatively programmed to generate a set of encipherment/decipherment public/private key pairs  406  and a set of signature/verification public/private key pairs  408 . These keys  406 ,  408  may be stored by the processor in the memory  422 . In the exemplary embodiment these keys  406 ,  408  may be RSA keys. However, it is to be understood that in alternative exemplary embodiments, keys for other encryption and digital signature algorithms and protocols may be generated. 
     After the sets of keys  406 ,  408  have been generated, the processor  420  may be operative to generate two certificate request messages  440  each containing one of the two generated public keys  410 ,  412  from the generated sets of keys  406 ,  408 . These certificate request messages  440  may be signed using the respective private keys  411 ,  413  which correspond to the public keys  410 ,  412  in each certificate request message  440 . Also, these messages may include a serial me number or other unique identifier of the EPP. In an exemplary embodiment, the certificate request messages may be constructed according to the PKCS # 10  Certification Request Syntax Standard format. The exemplary embodiment of the EPP may be operative to output the certificate request messages through its hardware interface  424  for purposes of communicating the certificate request messages to the initial CA. 
     In response to receiving the certificate request messages  440  the initial CA  402  may be operative to verify that the EPP has possession of the private keys  411   413  by verifying the digital signatures  442  of the messages  440  using the corresponding public key  410 ,  412  received in the messages  440 . After verifying the digital signatures of the messages  440 , the initial CA may generate and sign corresponding primary and secondary certificates  114  for each of the two public keys  410 ,  412  of the EPP. In addition, each of the certificates may include the serial number  415  of the EPP. 
     The EPP  404  may be operative to receive the newly generated primary and secondary certificates  114  through the hardware interface  424 . The EPP may also be operative to receive the primary and secondary certificates  416  of the initial CA through the hardware interface. These certificates  416  of the initial CA may include the primary and secondary public keys  418 ,  419  of the initial CA and may be self-signed with the private keys corresponding to the public keys  418 ,  419  of the initial CA. 
     The EPP is operative to use the public keys  418  and  419  from the certificates  416  of the initial CA to validate the certificates  414  of the EPP. Further, the EPP may verify that the public keys in the certificates  414  of the EPP match the original public keys  410 ,  412  generated by the EPP. Also, the EPP may verify that the serial number in the certificates matches the original serial number 415 of the EPP. 
     The EPP  404  may store the received certificates  414  of the EPP in the memory  422 . Also, the EPP  404  may store the public keys  418 ,  419  and/or the certificates  416  of the initial CA  402  in the memory  422 . The memory  422  may be comprised of a nonvolatile memory that is operative to preserve the keys  406 ,  408  and certificates  414 ,  416  in the memory  422 , during periods when the power has been removed from the EPP  404 . In the described exemplary embodiment, the public keys  410 ,  412  of the EPP may each be sent to the initial CA  402  in their own respective certificate request messages  440 . However, in alternative exemplary embodiments, both public keys  410 ,  412  of the EPP may be include in a single certificate request message. 
     In the exemplary embodiment, the host system  430  may also be operative to communicate with the initial CA  402  using the process previously described with respect to the EPP. The host system may generate its own sets of encipherment/decipherment public/private key pairs and signature/verification public/private key pairs. The host system may then enable one or more certificate request messages to be sent to an initial CA which includes the generated public keys of the host. The initial CA may issue corresponding encipherment/decipherment and signature/verification certificates for the host system. These certificates for the host system may be received by the host system along with the certificates of the initial CA for storage at the host system. In addition the initial CA may further issue both primary and secondary sets of the host certificates, where the first set is signed by the primary private key of the initial CA and the second set is signed by the secondary private key of the initial CA. 
     In the exemplary embodiment, the primary and secondary sets of certificates for the EPP include the same set of public keys of the EPP. However, in alternative exemplary embodiments, the EPP may generate both a primary set and a secondary set of encipherment/decipherment public/private key pairs and signature/verification public/private key pairs. The corresponding public keys from the primary set of keys may be forwarded to the initial CA to be integrated into the primary set of certificates of the EPP issued by the CA. The corresponding public keys from the secondary set of keys may be forwarded to the initial CA to be integrated into the secondary set of certificates of the EPP issued by the CA. In additional the exemplary primary and secondary host certificates may likewise be associated with separate sets of primary and secondary sets of encipherment/decipherment public/private key pairs and signature/verification public/private key pairs. 
     As discussed previously the certificates issued by the initial CA are exchanged between the host system  430  and the EPP  404 . The public keys  418 ,  419  of the initial CA may be used by the host system  430  and the EPP  404  to authenticate the exchanged certificates of the EPP and host system. The exemplary embodiment may use a large key size for the keys  418 ,  419  of the initial CA so as to make the forging of the certificates much more difficult. However to further increase security, the exemplary EPP and/or the host system may be operative to limit the number of initial certificate exchanges in order to prevent possible future exchanges using forged certificates. In addition, in the exemplary embodiment, initial certificate exchanges may be locked out once a remote terminal master key transfer has been completed. However, prior to the terminal master key transport, multiple certificate exchanges may be permitted between the host and the ATM for testing purposes. 
     In the exemplary embodiment, the initial certificate exchange between the host system and EPP may be initiated by an operator inputting commands into the ATM, which causes the ATM to communicate with a host system and begin the certificate exchange. FIG. 12 schematically shows the certificate exchange process between an ATM  602  and a host system  606  that is initiated by an operator. Here exemplary embodiments of the ATM  602  may generate and send to the host system  606  at least one message  604  in response to receiving a command from an operator to initiate the certificate exchange. In the exemplary embodiment, the message  604  may include for example an unsolicited status message or other types of messages which an ATM is capable of sending to a host system. In a Diebold 91XATM message protocol environment, for example, the unsolicited status message may include data in a status field which corresponds to “new network certificate required”, The unsolicited status message may also include data in a device ID field which corresponds to the EPP. 
     In response to receiving the message  604 , the host system may return to the ATM, a certificate containing the public key of the host system. In exemplary embodiments the host system may also be capable of initiating the sending of the certificate of the host to the ATM without first receiving a message  604  from the ATM. 
     As shown in FIG. 12, the host certificate  610  may be included in at least one message  608  being sent to the ATM. Such a message  608  may include for example a write command message or other types of messages which an ATM is capable of receiving from a host system. In a Diebold 91X ATM message protocol environment, for example, the write command message may correspond to a Write Command VII message with data in a key change field that includes the certificate  610  of the host system  606 . Such data for the certificate may use the PKCS # 7 : Cryptogyraphic Message Syntax Standard format. This message syntax may use the Abstract Syntax Notation One (ASN. 1 ) with Basic Encoding Rules (BER) and Distinguished Encoding Rules(DER) which is converted from octet (8-bit) strings to 7-bit ASCII using Base64 encoding. 
     In response to receiving the certificate  604  of the host system, the EPP may retrieve the public key of the initial CA from the memory of the EPP and use the retrieved public key to validate the signature on the certificate  610  of the host system. Also as discussed previously, the exemplary ATM may be operative to display a one-way hash of the public key of the host through a display device of the ATM. The ATM may require an operator to enter an input through an input device of the ATM which corresponds to a confirmation that the one-way hash number is valid. To verify the displayed one-way hash number, the operator may compare the displayed one-way hash number to another hash number that the operator independently knows corresponds to the public key of the host. If these described verifications are successful, the EPP may store the certificate of the host system  604  and/or the public key of the host in a memory of the EPP. 
     Also, the ATM  602  may return to the host system  606  at least one message  612  which includes data that is representative of a successful completion of the certificate transfer. Such a message  612  may include for example a solicited status message or other types of messages which an ATM is capable of sending to a host system. If the verifications of the certificate of the host system are unsuccessful, the message  612  may be returned with data representative of an error. In this described exemplary embodiment the ATM  602  may send messages  612  for each of the certificates (encipherment/decipherment or signature/verification) of the host system. In other exemplary embodiments, the ATM may request both certificates in a single message. 
     The EPP may also send its certificates to the host system. FIG. 13 schematically shows the certificate exchange process between an ATM  632  and a host system  636  that is initiated by the host system. Here the host system  306  may send to the ATM  632  at least one message  634  which requests on, of the certificates of the EPP  638  of the ATM. Such a message  634  may include for example an operational command message or other types of messages which an ATM is capable of receiving from a host system. In a Diebold 91X ATM message protocol environment, for example, the operational command message may include a command code that corresponds to requesting a certificate. The contents of the data field may indicate which public key certificate (encipherment/decipherment or signature/verification) is requested. The ATM  632  may respond by sending at least one message  640  containing the particular certificate  641  of the EPP that was requested by the host system. Such messages  640  may include for example a solicited status message or other types of messages which an ATM is capable of sending to a host system. In a Diebold 91X ATM message protocol environment, for example, the data corresponding to the certificate may be included in the buffer data field. As discussed previously, the data corresponding to the certificate may use the PKCS # 7 : Cryptographic Message Syntax Standard format. The message syntax may use the Abstract Syntax Notation One (ASN. 1 ) with Basic Encoding Rules (BER) and Distinguished Encoding Rules(DER) which is converted from octet (8-bit) strings to 7-bit ASCII using Base64 encoding. 
     The host system may validate the digital signature of the EPP using its copy of the public key of the initial CA. In this described exemplary embodiment the host system may send operational command messages for each of the certificates (encipherment/decipherment or signature/verification) of the EPP of the ATM. In other exemplary embodiments, the host system may request both certificates in a single request message. 
     As shown in FIG. 14, an exemplary embodiment of the EPP  504  may be manufactured to include the original public keys and/or original certificates  510  of an initial CA  508 . As discussed previously, the EPP may further acquire its own initial set of original certificates  506  that are issued by the initial CA  508 . Such original certificates may include the respective public encipherment and verification keys generated by the EPP. Also as discussed preciously, the EPP may acquire the original public keys and/or certificates  505  of the host system that were issued by the initial CA  508 . 
     As described herein, the EPP may store copies of the certificates of host systems and certificate authorities in a memory of the EPP. However, it is to be understood that in other exemplary embodiments, only the public keys included in the certificates of certificate authorities and host systems may be stored in the EPP. Other contents of the certificates of the certificate authorities and host systems may be discarded after validation of the certificates and storage of the public keys by the EPP. 
     In exemplary embodiments, the original certificates  506  of the EPP which were signed by the initial CA  508  may be used for terminal master key transfers. However, the institution or other entity operating the ATM  502  with the EPP  504  may wish to replace the initial CA  508  with a new CA  514 . As a result, exemplary embodiments of the EPP  504  may further be operative to replace the public keys and/or certificates of the initial CA  508  with new public keys and/or certificates of a new CA  514 . FIG. 14 shows an exemplary process  500  for replacing public keys and/or certificates in an EPP  504  of an ATM  502  when the initial or subsequent CA is replaced. 
     In an exemplary embodiment a host system  512  may initiate the replacement of the original public keys and/or certificates  510  of the initial CA  508  stored in the EPP. An exemplary embodiment of the host system  512  may send to the ATM  502  at least one message  522  including for example a write command message or other types of messages which an ATM is capable of receiving from a host system. The message  522  may include a new certificate  518  of the new CA  514 . In embodiments where the EPP requires both primary and secondary certificates of the new CA, the host system may send separate messages  522  for each certificate or may include both primary and secondary certificates in a single message. In the following description of the systems shown in FIGS. 10 and 11, each of the messages  522 ,  532 ,  540 ,  550  may refer to transferring only individual certificates or individual keys in the messages. However, it is to be understood that in other exemplary embodiments, the messages  522 ,  532 ,  540 ,  550  may be constructed to send multiple certificates or keys in each message. 
     In this described exemplary embodiment the new certificate  518  of the new CA  514  includes the new public key  516  of the new CA. In addition the new certificate  518  may be signed by the initial CA  508  using the private key  520  of the initial CA  508  to form the digital signature  524 . In a Diebold 91X ATM message protocol environment, for example, the data corresponding to the new certificate  518  of the new CA may be included in the New Key Data field of a Write Command VII Message. As discussed previously, the data corresponding to the certificate may use the PKCS # 7 : Cryptographic Message Syntax Standard format. The message syntax may use the Abstract Syntax Notation One (ASN. 1 ) with Basic Encoding Rules (BER) and Distinguished Encoding Rules(DER) which is converted from octet (8-bit) strings to 7-bit ASCII using Base64 encoding. 
     In the exemplary embodiment, the certificate of the new CA may be further signed by the host system  512  to form the digital signature  526 . Upon receipt of the message  522  by the ATM  502 , the exemplary EPP  504  is operative to validate the digital signature  524  of the initial CA and validate the digital signature  526  of the host system. In exemplary embodiments, the EPP may validate the digital signature  524  of the initial CA using the original public key and/or original certificate  5   10  of the initial CA. In addition the exemplary EPP  502  may validate the digital signature  526  of the host system using the original public key and/or original certificate  505  of the host system. 
     Once the new certificate  518  of the new CA has been validated, the new public key  516  and/or certificate  518  of the new CA may be stored in the EPP for use with authenticating new certificates issued by the new CA. Although the original public key and/or certificate  510  of the initial CA could be discarded after the new certificate  518  has been accepted, exemplary embodiments of the EPP may also retain the original public key and/or certificate  510  for use in re-commissioning the EPP. 
     After the new public keys  516  and/or new certificate  518  of the new CA  514  have been accepted by the EPP  504 , the exemplary ATM  502  may send to the host system  512  a message  582  which indicates that the replacement of the certificates for the CA was successful. Such a message  582  may include for example a solicited status message or other types of messages which an ATM is capable of sending to a host system. When the verification of the new certificate of the CA is unsuccessful, the message  582  returned may indicate an error. 
     After the E PP has received the new public keys  516  of the new CA  514 , the exemplary EPP  504  may require new certificates for the EPP which are signed by the new CA. To enhance security of the system, the exemplary embodiment of the EPP may also generate new public/private encipherment/decipherment and signature/validation key pairs  560  to replace the original key pairs  566 . 
     FIG. 15 schematically shows the process for updating the original public/private key pairs  566  of the EPP and corresponding original certificates  506  of the EPP. Here, the host system  512  may send to the ATM  502  at least one message  584  which includes data representative of a request that the EPP  504  generate new public/private key pairs  506 . Such a message  584  may include an operational command message or other types of messages which an ATM is capable of receiving from a host system. In the exemplary embodiment, the message A  584  may include a field which specifies which of the encipherment/decipherment or signature/verification keys pairs to update. In other exemplary embodiments, the message  584  may correspond to a request that both types of key pairs to be updated. 
     Once one of the new key pairs  560  has been generated, the ATM  502  may send to the host system  512  at least one message  586  which includes a certificate request message  532 . Such a message  586  may include for example a solicited status message or other types of messages which an ATM is capable of sending to a host system. The certificate request message  532  may request the issue of a new certificate for one or both of the corresponding newly generated public keys  562 ,  564 . In a Diebold 91X ATM message protocol environment, for example, the data corresponding to the certificate request message may be included in the buffer data field of the solicited status message. 
     The exemplary certificate request message  532  may include one or both of the corresponding newly generated public key  562 ,  564  of the EPP  504 . The certificate request messages  532  ma y also include the serial number  567  or other unique identifier of the EPP. In this described exemplary embodiment, the new public verification key  564  and the new public encipherment key  562  are sent to the host system in separate certificate request messages responsive to receiving separate messages  584  from the host which individual specify which of the key pairs to update. However, it is to be understood that in alternative exemplary embodiments, both public keys  562 ,  564  may be sent in a common certificate request message or the message  586  from the ATM may include separate certificate request messages for each public key. 
     When the certificate request message contains the new verification public key  564 , the EPP may sign the certificate request message  532  with the new private signature key  565  to form digital signature  534 . Also to authenticate the message to the host, the EPP may sign the certificate request  532  with its original private signature key of the original keys  566  to form the digital signature  535 . When the certificate request message contains the new encipherment public key  562  of the EPP, the certificate request message may first be signed with the new decipherment private key  563 , and may then be signed with the original decipherment private key from the original keys  566  to authenticate the message with the host. 
     In an exemplary embodiment the certificate request message  532  may include both the PKCS # 10 : Certification Request Syntax Standard format and the PKCS # 7 : Cryptographic Message Syntax Standard format. The messages may use the PKCS # 7  Signed-data content for the outer signature (using the original private signature or decryption key). The message may use the PKCS # 10  certificate request format for the inner data (using the new private signature or decryption key). Also as discussed previously, the message syntax may use the Abstract Syntax Notation One (ASN. 1 ) with Basic Encoding Rules (BER) and Distinguished Encoding Rules(DER) which is converted from octet (8-bit) strings to 7-bit ASCII using Base64 encoding. 
     Upon receipt of the certificate request messages  532 , the exemplary host system may validate the EPP signatures  534 ,  535  of the messages. After validating the signatures  534 ,  535 , the host system may cause the new CA  514  to issue an updated certificate  542  which includes the corresponding new public key  562 ,  564  of the EPP received in the certificate request message  532 . The updated certificate  542  may also include the serial number  567  or other unique identifier of the EPP. 
     The host system may be operative to send a message  540  to the ATM  502  which includes the updated certificate  542 . Such a message  540  may include for example write command messages or other types of messages that an ATM is capable of receiving from a host system. In a Diebold 91X ATM message protocol environment, for example, the data corresponding to the updated certificate  542  for the EPP may be included in the new key data field of a Write Command VII Message. In an exemplary embodiment the messages  540  for sending an updated certificate of the EPP may include the PKCS # 7 : Cryptographic Message Syntax Standard format. The messages may use the degenerate “certificate only” case of the Signed-data content type in which the inner content&#39;s data field is omitted and there are no signers. 
     The exemplary embodiment of the host system is operative to send at least one message  540  with one new certificate  542  of the EPP for each certificate request messages  532 . In alterative exemplary embodiments, the host system may send both the new encipherment/decipherment and signature/verification certificates  574 ,  576  in a single message  540  responsive to receiving one or more certificate request messages  522  that includes both public keys  562 ,  564  in a single message  586  from the ATM. 
     Before accepting the new certificate  542 , the EPP may verify that the new certificate was signed by the current CA, which in this described embodiment is the new CA  514 . In addition the EPP may verify that the public key in the new certificate  542  matches the current public key which in this described embodiment is one of the newly generated public keys  562 ,  564 . Also the EPP may verify that the serial number in the new certificate  542  matches the original serial number of the EPP. If the received new certificate is determined to be valid, the EPP may store it in the memory of the EPP. In addition the EPP may replace the original keys  566  with the newly generated public/private encipherment/decipherment or signature/validation key pairs  560  that correspond to the new certificate  542 . 
     Upon accepting the new certificate  542 , the exemplary EPP may return to the host system at least one message  550  which indicates that the new certificate  542  was successfully received. Such a message  550  may include for example a solicited status message  550  or other types of message which an ATM is capable of sending to a host system. In one exemplary embodiment, when the message  550  has been received and represents the acceptance of the new certificate  542 , the host system may replace the copy of the original certificate  506  of the EPP stored at the host system with the new certificate  542  of the EPP. In other exemplary embodiments, the original ATM certificates  506  stored at the host system may be replaced with new certificates  542  of the EPP by having the EPP of the ATM  504  send the new certificates to the host system. As discussed previously with respect to FIG. 13, the host system  536  may send a message  634  to the ATM  632  which requests one of the new certificates of the EPP. In response, the EPP  638  may return the requested new certificate in a message  640 . 
     In addition, the exemplary host system  512  may further send to the EPP, a set of new certificates  570  for the host system which are digitally signed by the new CA. This process may be initiated by the host system or an operator at the ATM. As discussed previously with respect to FIG. 12, when an operator initiates the transfer of the updated certificate of the host system to the ATM  502 , the ATM is operative to output a one-way hash of the new public key contained in the new certificate of the host through a display device of the ATM which can be independently verified by the operator. If the one-way hash is indicated to be valid by the operator, the EPP may accept and store the new public key and/or the new certificate of the host system in the memory of the EPP. 
     As with the certificates issued by the initial CA, the EPP  504  and host system  512  are further operative to use the exchanged new public keys and/or new certificates  542 ,  570  issued by the new CA to perform the steps involved with securely transferring a terminal master key from the host system  512  to the EPP  504 . In the exemplary embodiment, the steps described with respect to updating the CA and certificates may be performed a plurality of times whenever there is a requirement to change the CA and/or the public keys associated with the CA. 
     In exemplary embodiments, the EPP may be decommissioned in the field. Such a decommissioning may include clearing the public and private key pairs of the EPP and any public keys of the host system and a new CA. When the EPP is re-commissioned it may generate new public and private key pairs. The EPP may then generate new certificate request messages to be sent to the initial CA which include the newly generated public keys and the serial number of the EPP. As discussed previously, the initial CA may issue corresponding primary and secondary certificates for each of the new public keys of the EPP. 
     Computer software used in operating the automated transaction machines and connected computers may be loaded from articles of various types into the respective computers. Such computer software may be included on and loaded from one or more articles such as diskettes or compact disks. Such software may also be included on articles such as hard disk drives, tapes or ready only memory devices. Other articles which include data representative of the instructions for operating computers in the manner described herein are suitable for use in achieving operation of transaction machines and systems in accordance with exemplary embodiments. 
     The exemplary embodiments of the automated banking machines and systems described herein have been described with reference to particular software components and features. Other embodiments of the invention may include other or different software components which provide similar functionality. 
     Thus the new automated banking machine and system and method achieves one or more of the above stated objectives, eliminates difficulties encountered in the use of prior devices and systems, solves problems and attains the desirable results described herein. 
     In the foregoing description certain terms have been used for brevity, clarity and understanding. However no unnecessary limitations are to be implied therefrom because such terms are for descriptive purposes and are intended to be broadly construed. Moreover the descriptions and illustrations herein are by way of examples and the invention is not limited to the details shown and described. 
     In the following claims any feature described as a means for performing a function shall be construed as encompassing any means capable of performing the recited function and shall not be deemed limited to the particular means shown in the foregoing description or mere equivalents thereof. The description of the exemplary embodiment included in the Abstract included herewith shall not be deemed to limit the invention to features described therein. 
     Having described the features, discoveries and principles of the invention, the manner in which it is constructed and operated and the advantages and useful results attained; the new and useful structures, devices, elements, arrangements, parts, combinations, systems, equipment, operations, methods, processes and relationships are set forth in the appended claims.