Abstract:
Methods, apparati, and computer-readable media for providing authorization and other services. In a preferred embodiment, an authorization service includes both a messaging specification and a set of rules that govern its use. A first customer wishing to use the authorization service prepares a request that complies with the service&#39;s messaging specification and transmits it to a first participant. The first participant transmits the request to a second participant, which processes the request according to authorization information provided by a second customer and rules that have been specified for the service. The second participant then prepares a response that complies with the service&#39;s messaging specification.

Description:
RELATED APPLICATIONS  
       [0001]     This patent application is a continuation of U.S. patent application Ser. No. 09/950,059, filed Sep. 10, 2001, which patent application claims priority upon U.S. provisional patent application Ser. No. 60/231,313, filed Sep. 8, 2000, entitled Authorization/Credential Service and Authorization/Credential Service Proposal, U.S. provisional patent application Ser. No. 60/231,315, filed Sep. 8, 2000, entitled Authorization/Credential Service Proposal, and U.S. provisional patent application Ser. No. 60/231,318, filed Sep. 8, 2000, entitled Authorization/Credential Service, all four of which patent applications are hereby incorporated by reference in their entireties into the present patent application. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The world of electronic commerce has created new challenges to establishing relationships between contracting parties. One of those challenges springs from the fact that the parties to the transaction cannot see or hear each other, and cannot otherwise easily confirm each other&#39;s identity and authority to act.  
         [0003]     One remedy for this problem is to provide each contracting party with a private key for signing transmitted messages. The signing party makes available an associated public key that decrypts messages signed with the party&#39;s private key, and thus enables a receiving party to confirm the identity of the sender.  
         [0004]     But the sender&#39;s public key may not be known a priori to the recipient. In that event, the sender may transmit with its signed message a digital certificate issued by a certification authority. The certificate is itself a signed electronic document (signed with the private key of the certification authority) certifying that a particular public key is the public key of the sender.  
         [0005]     In some cases, the recipient may be unfamiliar with the public key of the certification authority or may not know whether the certificate is still valid. In that event, the recipient may wish to check the validity of the certificate. In addition, the recipient may wish to check whether or not the sender is authorized to sign the transmitted message.  
       DISCLOSURE OF INVENTION  
       [0006]     Methods, apparati, and computer-readable media for providing authorization and other services. In a preferred embodiment, these services are provided within the context of a four-corner trust model. The four-corner model preferably comprises a subscribing customer (sometimes referred to as the “buyer”) and a relying customer (sometimes referred to as the “seller”), who engage in an on-line transaction.  
         [0007]     In a preferred embodiment, the subscribing customer is a customer of a first financial institution, referred to as an issuing participant. The issuing participant acts as a certification authority for the subscribing customer and issues the subscribing customer a hardware token including a private key and a digital certificate signed by the issuing participant.  
         [0008]     In a preferred embodiment, the relying customer is a customer of a second financial institution, referred to as the relying participant. The relying participant acts as a certification authority for the relying customer and issues the relying customer a hardware token including a private key and a digital certificate signed by the relying participant. The system also includes a root entity that maintains a root certification authority that issues digital certificates to the issuing and relying participants.  
         [0009]     The present system provides a generalized framework for designing and implementing one or more authorization services that may be used to confirm the authority of an individual to act on behalf of a customer. Such authorization services may be used, for example, to determine whether a particular employee is authorized to purchase certain goods, negotiate a particular contract, or undertake to perform in a particular manner on behalf of its employer.  
         [0010]     In a preferred embodiment, authorization services in the present system may be designed and implemented in accordance with the following process. First, a customer and its participant work together to define a desired authorization service. The authorization-service definition preferably includes both a messaging specification for the service and a set of rules that govern its use, as described in more detail below.  
         [0011]     Second, the proposed authorization service is presented to a policy management authority maintained by the root entity for approval. The policy management authority reviews the proposed authorization service for compliance with system operating rules and specifications promulgated by the root entity.  
         [0012]     Third, if the proposed authorization service is approved by the root-entity policy management authority, the service is implemented within the four-corner model.  
         [0013]     When a relying customer wishes to utilize an approved authorization service, it prepares an authorization request that complies with the service&#39;s messaging specification and transmits the request to its relying participant.  
         [0014]     The relying participant transmits the request to the issuing participant which processes the request in accordance with authorization information provided by the subscribing customer as well as any implementation rules that have been specified for the service. The issuing participant then prepares an authorization response that complies with the service&#39;s messaging specification and transmits the response to the relying participant. The relying participant transmits the authorization response to its relying customer.  
         [0015]     The features and advantages described in the specification are not all inclusive, and many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims hereof. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     The above summary of the invention will be better understood when taken in conjunction with the following detailed description and accompanying drawings, in which:  
         [0017]      FIG. 1  is a block diagram of a preferred embodiment of a four-corner model suitable for use in the present system;  
         [0018]      FIG. 2  is a block diagram of a preferred embodiment showing components provided at entities in the present system;  
         [0019]      FIG. 3  illustrates a preferred embodiment for establishing an authorization service;  
         [0020]      FIG. 4  illustrates a preferred embodiment of a process flow for using an authorization service;  
         [0021]      FIG. 5  illustrates a preferred embodiment of certain messages transmitted in the preferred embodiment of  FIG. 4 .  
         [0022]      FIG. 6  illustrates a preferred embodiment of a process flow in which an authorization service and a certificate validation service are bundled together; and  
         [0023]      FIG. 7  illustrates a preferred embodiment of certain messages transmitted in the preferred embodiment of  FIG. 6 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]     The present disclosure relates to a system and method for providing authorization and other services. In a preferred embodiment, these services are provided within the context of a four-corner trust model. A preferred embodiment of a four-corner model suitable for use in the present system is shown in  FIG. 1 .  
         [0025]     As shown in  FIG. 1 , the four-corner model preferably comprises a first institution  102  and a second institution  104 . First institution  102  is referred to as the “issuing participant” because it is a participant in the present system and issues to its customers tokens that include a private key and a digital certificate signed by the issuing participant, as described below. Second institution  104  is referred to as the “relying participant” because it is a participant in the present system and its customers rely on representations made by issuing participant  102  and issuing participant  102 &#39;s customers, as described below. Participants  102 ,  104  may preferably be banks or other financial institutions.  
         [0026]     Also shown in  FIG. 1  are a first customer  106  and a second customer  108 . First customer  106  and second customer  108  are preferably customers of issuing participant  102  and relying participant  104 , respectively. First customer  106  is referred to as the “subscribing customer” because this customer subscribes to services provided by issuing participant  102 . First customer  106  is also sometimes referred to as the “buyer” because it typically fills that role in transactions with second customer  108 , as described below.  
         [0027]     Second customer  108  is referred to as the “relying customer” because it relies on representations made by both issuing participant  102  and subscribing customer  106 . Second customer  108  is also sometimes referred to as the “seller” because it typically fills that role in transactions with first customer  106 , as described below. It should be recognized, however, that although the description below speaks primarily in terms of a buyer  106  and a seller  108 , first customer  106  and second customer  108  may instead have different roles in a given transaction. For example, first customer  106  may be a borrower repaying a loan to second customer  108 .  
         [0028]     As will be recognized, although the preferred embodiments described below speak primarily in terms of customer  106  acting as a subscribing customer and customer  108  acting as a relying customer, the roles of these two customers may at times be reversed, even within a single transaction and with respect to a single document. For example, in connection with a particular transaction, customers  106 ,  108  may prepare a contract to be signed by both parties. With respect to customer  106 &#39;s signature on the contract, customer  106  is the subscribing customer and customer  108  is the relying customer. By contrast, with respect to customer  108 &#39;s signature on the contract, customer  108  is the subscribing customer and customer  106  is the relying customer.  
         [0029]     It should also be noted that each customer  106 ,  108 , may be a business entity, such as a corporation, that employs many individuals. In such cases, customers  106 ,  108  preferably authorize some or all of these individual employees to transact and utilize system services on their behalf. Issuing participant  102  preferably issues a separate smartcard token having a distinct private key and associated digital certificate to each authorized employee of subscribing customer  106 . Similarly, relying participant  104  (in its capacity as “issuing participant” to relying customer  108 ) preferably issues a separate smartcard token having a distinct private key and associated digital certificate to each authorized employee of relying customer  108 . The digital certificates preferably include the individual employee&#39;s name and identify the customer for whom he or she works. In an alternative embodiment, the private key may instead be included in a software token provided to the individual.  
         [0030]     It should be recognized that although the description that follows may speak in terms of messages or other data being signed by a “subscribing customer” or “relying customer,” the signature may in fact typically be created by an individual employee using his or her digital certificate and associated private key acting on behalf of his or her employer.  
         [0031]     Also shown in  FIG. 1  is a root entity  110 . Root entity  110  is preferably an organization that establishes and enforces a common set of operating rules for facilitating electronic commerce and electronic communications. Root entity  110  may be owned jointly by a plurality of banks and/or other financial institutions that have agreed to adhere to these operating rules. One exemplary embodiment of such a root entity is described in copending U.S. application Ser. No. 09/502,450, filed Feb. 11, 2000, entitled System and Method for Providing Certification Related and Other Services and in copending U.S. application Ser. No. 09/657,623, filed Sep. 8, 2000, entitled System and Method for Providing Certificate-Related and Other Services, which are hereby incorporated by reference.  
         [0032]      FIG. 2  is a block diagram of a preferred embodiment showing components provided at each entity in the present system. As shown in  FIG. 2 , participants  102 ,  104 , and root entity  110  are each preferably provided with a transaction coordinator  202  that serves as a gateway for transmitting and receiving all inter-entity messages related to services provided by the present system. Transaction coordinators  202  provide a single interface to issuing participant  102 &#39;s and relying participant  104 &#39;s on-line services and implement safeguards necessary to ensure secure electronic communications between transaction coordinators  202  and other entities in the four-corner model, as described in copending U.S. application Ser. No. 09/657,605, filed on Sep. 8, 2000, entitled System and Method for Providing Certificate Validation and Other Services, which is hereby incorporated by reference. Each transaction coordinator  202  is preferably provided with an associated hardware security module (HSM)  218  for signing and verifying messages. Participants  102 ,  104 , and root entity  110  are each further preferably provided with an OCSP responder  204  and associated hardware security module (HSM)  206  for signing and verifying signatures on messages.  
         [0033]     Root entity  110  is also preferably provided with a central repository  260 . Central repository  260  is preferably adapted to store data, such as, for example, messaging specification and other data as described in more detail below.  
         [0034]     Participants  102  and  104  are each preferably provided with a directory  270 . Directory  270  is preferably adapted to store data, such as, for example, credential records and messaging specification data, as described in more detail below.  
         [0035]     Subscribing customer  106  is preferably provided with a Web browser  224  adapted to receive and transmit information via the Internet. Subscribing customer  106  is also preferably provided with a smartcard subsystem  226  adapted to sign electronic messages. In a preferred embodiment, smartcard subsystem  226  may include a smartcard reader, a smartcard driver, a smartcard token, and other software, as described in U.S. provisional application Ser. No. 60/224,994, filed Aug. 14, 2000, entitled Signing Interface Requirements, Smart Card Compliance Requirements, Warranty Service Functional Requirements, and Additional Disclosure and copending U.S. application Ser. No. 09/928,999, filed Aug. 14, 2001, entitled System and Method for Secure Smartcard Issuance, which are hereby incorporated by reference. In a preferred embodiment, the smartcard token is issued to subscribing customer  106  by its issuing participant  102 .  
         [0036]     Subscribing customer  106  is also preferably provided with a signing interface  225 . Signing interface  225  is adapted to invoke smartcard  226  to execute a digital signature, as described in U.S. provisional application Ser. No. 60/224,994, filed Aug. 14, 2000, entitled Signing Interface Requirements, Smart Card Compliance Requirements, Warranty Service Functional Requirements, and Additional Disclosure and U.S. application Ser. No. 09/929,035, filed Aug. 14, 2001, entitled System and Method for Facilitating Signing by Buyers in Electronic Commerce, which are hereby incorporated by reference.  
         [0037]     Relying customer  108  is preferably provided with a Web server  220  adapted to receive and transmit information via the Internet and a bank interface  222  for accessing system services. An exemplary bank interface is described in copending U.S. application Ser. No. 09/657,604, filed on Sep. 8, 2000, entitled System and Method for Facilitating Access by Sellers to Certificate-Related and Other Services, which is hereby incorporated by reference. Relying customer  108  is preferably further provided with an HSM  250  for signing and verifying signatures on messages.  
         [0038]     Customers  106 ,  108  are also each preferably provided with a directory  280  that is adapted to store data, such as, for example, credential records and messaging specification data, as described in more detail below.  
         [0039]     In a preferred embodiment, each system entity is further preferably provided with two digital certificates (and corresponding private keys) to facilitate authentication: an identity certificate and a utility certificate.  
         [0040]     The identity private key is used to produce digital signatures that are required by root entity  110  as evidence of an entity&#39;s contractual commitment to the contents of an electronic transaction, such as a purchase order.  
         [0041]     The utility private key is used to provide additional transactional security. Typically, utility certificates are used to support secure socket layers (SSL), to sign secure multipurpose internet mail extension (S/MIME) messages, and for other utility applications. Any reference in this document to the term “certificate” refers to an identity certificate unless otherwise stated.  
         [0042]     In a preferred embodiment, root entity  110 , in its capacity as a certification authority, uses a root private key to create the digital certificates of each system participant (e.g., issuing participant  102  and relying participant  104 ). In addition, it uses the root private key to create digital certificates for each system component maintained by root entity  110  that has digital signing capability, including OCSP responder  204   R  and transaction coordinator  202   R .  
         [0043]     In addition, each system participant (e.g., issuing participant  102  and relying participant  104 ), in its capacity as a certification authority, uses the private key associated with its certificate from root entity  110  to create the digital certificates of its customers (e.g., subscribing customer  106  and relying customer  108 ). In addition, it uses this private key to create digital certificates for each system component that it maintains that has digital signing capability, including its OCSP responder  204  and transaction coordinator  202 . In an alternative embodiment, the digital certificates for system components with digital signing capability that are maintained by a participant may be issued by root entity  110 .  
         [0044]     It should be noted that the system entities may each be provided with additional components not shown in  FIG. 2 , such as the components described in copending U.S. application Ser. No. 09/657,605, filed on Sep. 8, 2000, entitled System and Method for Providing Certificate Validation and Other Services, U.S. provisional application Ser. No. 60/224,994, filed Aug. 14, 2000, entitled Signing Interface Requirements, Smart Card Compliance Requirements, Warranty Service Functional Requirements, and Additional Disclosure, U.S. provisional application Ser. No. 60/259,796, filed Jan. 4, 2001, entitled Warranty Manager Application Programming Interface, Warranty Messaging Specification, and Warranty Manager Functional Requirements, and copending U.S. application Ser. No. 09/928,998, filed Aug. 14, 2001, entitled System and Method for Providing Warranties in Electronic Commerce.  
         [0000]     Overview of Authorization Services  
         [0045]     The authorization services described herein provide a mechanism by which a first customer (e.g., customer  108 ) may confirm the authority of an individual to act on behalf of a second customer (e.g., customer  106 ). For example, authorization services may be used to confirm the authority of an individual to sign a particular document or to undertake a particular financial or performance obligation on behalf of the second customer. More specifically, authorization services maybe used, to cite just a few specific examples, to determine whether a particular employee is authorized to purchase a particular class of goods, negotiate a particular type of contract, or undertake to perform in a particular manner on behalf of the second customer.  
         [0046]     It should be recognized that the present system is intended to support a wide variety of authorization services that are preferably tailored to the business needs of a particular customer or industry. It is therefore impossible to describe completely every possible authorization service that may be supported by the present system. Rather, the description below provides a generalized framework for defining and implementing authorization services in a variety of business settings.  
         [0047]     To facilitate understanding of this generalized framework, an exemplary embodiment for defining and implementing a particular authorization service is described below. The exemplary embodiment comprises a hypothetical subscribing customer, ABC Co., that is a customer of an issuing participant, Bank A, and a hypothetical relying customer XYZ Co., that is a customer of a relying participant, Bank B. ABC Co. employs an office manager, known as John Smith, who is authorized to transact on behalf of ABC Co. in particular ways, as described in more detail below.  
         [0048]     As noted above, in a preferred embodiment, authorization services are designed and implemented in the present system using the following steps. First, a customer and its participant work together to define a desired authorization service. The authorization-service definition preferably includes both a messaging specification for the service and a set of rules that govern its use, as described in more detail below.  
         [0049]     Second, the proposed authorization service is presented to a policy management authority maintained by root entity  110  for approval. The policy management authority reviews the proposed authorization service for compliance with system operating rules and specifications promulgated by root entity  110 .  
         [0050]     Third, if the proposed authorization type is approved by the root-entity policy management authority, the service is implemented within the four-corner model.  
         [0051]     The first and second steps are described in more detail in connection with  FIG. 3  below. The third step is described in more detail in connection with  FIGS. 4-7  below.  
         [0000]     Establishing an Authorization Service  
         [0052]      FIG. 3  illustrates a preferred embodiment for establishing a new authorization service. As shown in  FIG. 3 , in step  301 , subscribing customer  106  and issuing participant  102  work together to broadly identify the parameters of an authorization service to be defined. For example, it may be determined that it would be useful to define an authorization service for ABC Co. to be used in authorizing purchase of goods or services by ABC Co. employees.  
         [0053]     In step  302 , subscribing customer  106  and issuing participant  102  work together to identify the particular customer and employee information needed to respond appropriately to such an authorization request. For example, it may be determined that each employee of ABC Co. has a title and that the types and amount of goods and services that the employee is authorized to obtain on behalf of ABC Co. are a function of that title. As will be recognized, this information will typically vary significantly from authorization service to authorization service as a function of the customer, industry, or type of authorization desired.  
         [0054]     In step  303 , subscribing customer  106  and issuing participant  102  work together to define a credential-record format for storing the categories of information (e.g., title, purchasing limit) identified in step  302 . This credential-record format is preferably customized as appropriate for the particular customer and industry to which the authorization service pertains.  
         [0055]     In a preferred embodiment, each credential record comprises one or more pairs of roles and attributes. A role is a characteristic relevant to the authority of an individual to take a particular action. An attribute represents the particular value assigned to a role for a given individual.  
         [0056]     For example, in the exemplary embodiment, it may be determined that each credential record should comprise the following roles:  
         [0057]     (1) Name  
         [0058]     (2) Title  
         [0059]     (3) Purchasing Authority  
         [0060]     (4) Purchasing Limit  
         [0061]     An exemplary set of attributes for these roles may be:  
         [0062]     (1) John Smith  
         [0063]     (2) Office Manager  
         [0064]     (3) Office Supplies  
         [0065]     (4) $1,000  
         [0066]     In step  304 , subscribing customer  106  and issuing participant  102  work together to identify any additional information that may be necessary to properly respond to authorization requests for the authorization type being defined. In a preferred embodiment, this information may include definition information and mapping information.  
         [0067]     Definition information is information used to construe particular attributes assigned to one or more employees of subscribing customer  106 . For example, as noted above, the purchasing-authority role for ABC Co.&#39;s office manager may be assigned the attribute “Office Supplies.” Definition information is preferably used to define the scope of this attribute. For example, definition information may be provided that defines “Office Supplies” as including pens, pencils, paper, adhesive tape, etc., but as excluding (either explicitly or by implication) desks, telephones, photocopy machines, etc. As described below, Bank A may refer to this definition information in responding to authorization requests concerning the purchasing authority of John Smith.  
         [0068]     Mapping information is information used to interpret an authorization request received from an entity that uses different terminology than subscribing customer  106  to describe the same things. For example, seller XYZ Co. may be located in the United Kingdom where the term “sellotape” is used to described what ABC Co. (located, for example, in the United States) would refer to as “adhesive tape.” Mapping information may be used to translate terms in an authorization request into appropriate terminology that matches that used by ABC Co.  
         [0069]     Additional mapping data may also preferably be maintained by issuing participant  102  to allow, for example, for currency conversion. Thus, for example, if seller XYZ Co. is located in the United Kingdom, it may specify a purchase amount in an authorization request in pounds sterling. Bank A may use dynamically-maintained mapping information to translate the purchase amount to dollars if, for example, ABC Co. specified its employee purchasing limits in that currency.  
         [0070]     In step  305 , issuing participant  102  and subscribing customer  106  preferably work together to create a messaging specification that defines a format for authorization requests and responses to be used in connection with the defined authorization service. As noted, the present system is intended to support a wide variety of authorization services each of which may be defined as desired by issuing participant  102  and subscribing customer  106 . Accordingly, in a preferred embodiment, the messaging specification may define messages in any suitable format such as extensible markup language (XML), hypertext markup language (HTML), etc.  
         [0071]     For purposes of the exemplary embodiment described herein, it will be assumed that all messages are to be defined in XML format. As such, the messaging specification created by issuing participant  102  and subscribing customer  106  preferably comprises a document type definition (DTD) that provides the formal description of all valid XML authorization request and response messages used in connection with the authorization service being defined. Exemplary embodiments for such authorization request and response messages are described below.  
         [0072]     In a preferred embodiment, an authorization service may be designed to support static authorization requests, dynamic authorization requests, or both.  
         [0073]     A dynamic authorization request is a request for approval that an individual is authorized to perform a certain act or undertake a particular transaction. For example, a dynamic authorization request may specify that a proposed transaction has a value of $500 and seek to determine whether a particular individual is authorized to transact in that amount. A dynamic authorization response preferably returns a Boolean value (e.g., “Authorized” or “Not Authorized”).  
         [0074]     A static authorization request is a request for the attribute(s) of one or more roles associated with a particular individual. For example, a static request may seek the signing limit of a particular corporate officer. A static authorization response returns the particular attribute(s) requested.  
         [0075]     In step  306 , issuing participant  102  and subscribing customer  106  preferably work together in order to define a set of implementation rules that govern use of the authorization service being defined. As noted above, the present system is designed to be flexibly adaptable to the needs of various businesses in various industries. Accordingly, it is impossible to create a complete list of all such rules that might be proposed by a particular subscribing customer  106  and/or issuing participant  102 . Illustrative examples of such rules, however, may include the following:  
         [0076]     1. Issuing participant  102  may respond to a request for authorization concerning purchase of office supplies only if the request is received from a company that sells office supplies.  
         [0077]     2. Issuing participant  102  may respond to a request for authorization concerning purchase of office supplies only if the request is received from a company on a list of approved suppliers established by subscribing customer  106 .  
         [0078]     3. Issuing participant  102  may respond to a request for authorization concerning purchase of office supplies only if the request is received from a particular company, e.g., XYZ Co.  
         [0079]     4. Issuing participant  102  may respond to a request for authorization concerning purchase of office supplies only if the request is received from an individual with a title of “sales manager.” 
         [0080]     5. Issuing participant  102  may respond to a request for authorization concerning purchase of office supplies only if the request is received from a particular individual employed by XYZ Co., e.g., Jane Doe.  
         [0081]     It should be noted that the implementation rules may differ as a function of authorization-request type (i.e., a static vs. dynamic authorization request). In particular, a subscribing customer  106  may wish to establish more restrictive rules for responding to static authorization requests than dynamic information requests.  
         [0082]     It should also be noted that it may often be possible to enforce one or more implementation rules by properly defining the messaging specification for the proposed service. For example, a subscribing customer  106  may wish to permit issuing participant  102  to respond to authorization requests only from relying customers  108  that are in possession of a signed purchase order from subscribing customer  106 . This implementation rule may be enforced by defining an authorization-request message format that includes a signed-purchase-order field in which relying customer  108  must include a signed purchase order from subscribing customer  106 .  
         [0083]     In a preferred embodiment, the implementation rules may also define access controls that limit the ability of relying customers to obtain the messaging formats for the proposed service. As will be recognized, the very structure of an authorization-request or authorization-response message, and the fields it comprises, may reveal valuable business information regarding the structure of a business entity. Such message-format data may also provide an attacker with information that might be useful in generating forged authorization requests or responses. Accordingly, in a preferred embodiment, the implementation rules also define access controls that limit access to messaging specification data for the proposed service. For example, access controls may be used to determine whether or not a particular relying customer  108  is entitled to receive the message format for a particular type of authorization request. In a preferred embodiment, these implementation rules are typically enforced by root entity  110  which is responsible for responding to requests for message-format data, as described in more detail below.  
         [0084]     In step  307 , issuing participant  102  presents the proposed authorization service including its messaging specification and implementation rules to a policy management authority maintained by root entity  110 . In step  308 , the root-entity policy management authority reviews the proposed service for compliance with system operating rules and specifications promulgated by root entity  110  and determines whether or not to approve the proposed service.  
         [0085]     If the root-entity policy management authority does not approve the proposed service, it notifies issuing participant  102  of this fact (step  309 ). The policy management authority may include with the denial suggested amendments to the messaging specification or implementation rules that would conform the authorization service to the operating rules and specifications promulgated by root entity  110  and permit approval of the proposed service.  
         [0086]     If the root-entity policy management authority approves the proposed service, then, in step  310 , root entity  110  stores the messaging specification and implementation rules for the service in central repository  260  and notifies issuing participant of the approval.  
         [0087]     Once approval notification is received, issuing participant  102  stores the approved messaging specification and implementation rules in directory  270  and notifies subscribing customer  106  of the approval (step  311 ). In step  312 , subscribing customer  106  supplies attribute information to issuing participant  102  to populate credential records for subscribing customer  106 &#39;s employees. For example, as noted above, ABC Co. may have an employee whose name is John Smith, whose title is “Office Manager” and who is therefore authorized to purchase up to $1000 of office supplies. In the exemplary embodiment, ABC Co. would transmit this attribute information (and analogous information for its other employees) to Bank A.  
         [0088]     In step  313 , issuing participant  102  establishes a credential record for each employee of subscribing customer  106  identified to it in step  312 . In the exemplary embodiment, for example, a credential record for John Smith may appear as follows:  
         [0089]     Name=John Smith  
         [0090]     Title=Office Manager  
         [0091]     Purchasing Authority=Office Supplies  
         [0092]     Purchasing Limit=$1,000  
         [0093]     In step  314 , issuing participant  102  stores the credentials records in directory  270 . In a preferred embodiment, this information may also be stored at subscribing customer  106  in directory  280 .  
         [0094]     The authorization service is now ready for use by system customers, as described in the following section.  
         [0000]     Authorization Service Process Flow  
         [0095]     A preferred embodiment of a process flow for using an approved authorization service is now described in connection with  FIGS. 4-5 . It should be recognized that the present system is intended to provide authorization services in a wide variety of situations in which one entity might seek authorization of another to transact or undertake some obligation. It is therefore impossible to describe completely every possible situation in which the authorization services of the present system might be used. The exemplary preferred embodiment described below describes a typical example (purchase of goods by one customer from another) in which authorization of an individual might be sought. It will be recognized, however, that the authorization services of the present system may be used in many other circumstances such as to confirm the authorization of one individual to negotiate a particular contract before commencing negotiations (which may be time-consuming and costly) with that individual.  
         [0096]     For purposes of the present exemplary embodiment, it will be assumed that the components shown in  FIG. 2  as being associated with the subscribing customer are owned and maintained by ABC Co. and assigned for use to John Smith, its office manager. It will further be assumed that the components shown in  FIG. 2  as being associated with the relying customer are owned and maintained by XYZ Co. It will further be assumed that the components shown in  FIG. 2  as being associated with the issuing participant and relying participant are owned and maintained by Bank A and Bank B, respectively.  
         [0097]     Beginning with  FIG. 4 , in step  401 , John Smith, the office manager for ABC Co., visits the Web site of XYZ Co. using his browser  224 . The parties preferably authenticate themselves to each other over an SSL session with their utility keys.  
         [0098]     Once John Smith agrees to a transaction (e.g., to purchase $200 of adhesive tape), Web server  220  communicates data to be digitally signed to browser  224  (e.g., a purchase order for the agreed to transaction) (step  402 ). In step  403 , the data to be signed is forwarded to smartcard subsystem  226  which signs the data to create a digitally-signed document.  
         [0099]     In step  404 , browser  224  receives the digitally-signed document and transmits it to Web server  220  or another appropriate location specified by XYZ Co. In a preferred embodiment, this signing process may be facilitated by using a signing interface  225  to invoke smartcard subsystem  226 , as described in U.S. provisional application Ser. No. 60/224,994, filed Sep. 8, 2000, entitled Signing Interface Requirements, Smart Card Compliance Requirements, Warranty Service Functional Requirements, and Additional Disclosure and copending U.S. application Ser. No. 09/929,035, filed Aug. 14, 2001, entitled System and Method for Facilitating Signing by Buyer&#39;s in Electronic Commerce, which are hereby incorporated by reference.  
         [0100]     In step  405 , XYZ Co. receives the digitally-signed document. In step  406 , XYZ Co. decides to confirm that John Smith is authorized to sign the purchase order.  
         [0101]     In step  407 , XYZ Co. determines whether it has previously obtained the appropriate message format for the desired authorization request to be created. As noted, the desired authorization request may be a static authorization request or a dynamic authorization request depending on the type of information that XYZ Co. would like to obtain. If XYZ Co. has previously obtained the appropriate message format, processing proceeds to step  416 , described below.  
         [0102]     Otherwise, in step  408 , XYZ Co. generates a request for the appropriate authorization-request message format, signs the request, and sends the request to Bank B (message  1  in  FIG. 5 ). In step  409 , Bank B transmits the request to root entity  110  (message  2  in  FIG. 5 ).  
         [0103]     In step  410 , root entity  110  receives the request and retrieves from central repository  260  the access-control implementation rules developed by Bank A and ABC Co. for the authorization service identified in the request. In step  411 , root entity  110  applies these access-control implementation rules to determine whether or not XYZ Co. is authorized to receive the requested authorization-request message format.  
         [0104]     If XYZ Co. is not authorized to receive the requested message format, then, in step  412 , root entity  110  generates a rejection message indicating this fact, signs it, and transmits it to Bank B (message  3  in  FIG. 5 ). In step  413 , Bank B transmits the rejection message to XYZ Co. (message  4  in  FIG. 5 ), and processing concludes.  
         [0105]     Otherwise, in step  414 , root entity  110  retrieves from central repository  260  the requested authorization-request message format, creates a signed message that includes the requested message format, and transmits the message to Bank B (message  5  in  FIG. 5 ). In step  415 , Bank B transmits the message to XYZ Co. (message  6  in  FIG. 5 ).  
         [0106]     In step  416 , XYZ Co. uses the authorization-request message format to generate an authorization request for some aspect of the transaction documented by the digitally-signed document.  
         [0107]     Assuming for purposes of the present exemplary embodiment that the authorization service permits a relying customer to make a dynamic request to determine whether an employee of ABC Co. is authorized to purchase a particular type and value of goods, an exemplary dynamic authorization request message might include the following fields:  
         [0108]     Authorization Request Message Code (indicating that the message is a request for authorization and specifying a particular authorization service by number)  
         [0109]     Request Type (indicating whether the request is a static request or a dynamic request)  
         [0110]     Request ID (unique identifier generated by relying customer  108 )  
         [0111]     Relying Customer Name (e.g., XYZ Co.)  
         [0112]     Subscribing Customer Name (e.g., ABC Co.)  
         [0113]     Subscribing Customer Employee (e.g., John Smith)  
         [0114]     Transaction Type (e.g., purchase, rental, etc.)  
         [0115]     Transaction Item  
         [0116]     Transaction Amount  
         [0117]     An exemplary XML implementation of a dynamic authorization request generated for John Smith&#39;s authorization to purchase $200 worth of adhesive tape may be as follows:  
         [0000]     &lt;AuthorizationRequestServiceNo 12345&gt; 
         [0118]     &lt;RequestType Type=“dynamic”/&gt; 
         [0119]     &lt;RequestId Id=“0034021”/&gt; 
         [0120]     &lt;RCNameAndId Id=“123456” Name=“XYZ Co.”/&gt; 
         [0121]     &lt;SCNameAndId Id=“654321” Name=ABC Co.”/&gt; 
         [0122]     &lt;SCEmployeeNameAndId Id=“13579” Name=“John Smith”/&gt; 
         [0123]     &lt;TransactionType Type=“purchase”/&gt; 
         [0124]     &lt;TransactionItem Item=“adhesive tape”/&gt; 
         [0125]     &lt;TransactionAmount Currency=“USD” Amount=“200”/&gt; 
         [0000]     &lt;/AuthorizationRequestServiceNo 12345&gt; 
         [0126]     Alternatively, assuming for purposes of the present exemplary embodiment that the authorization service permits a relying customer to make a static request to determine the purchasing authority of an employee of ABC Co., an exemplary static authorization request message might include the following fields:  
         [0127]     Authorization Request Message Code (indicating that the message is a request for authorization and specifying a particular authorization service by number)  
         [0128]     Request Type (indicating whether the request is a static request or a dynamic request)  
         [0129]     Request ID (unique identifier generated by relying customer  108 )  
         [0130]     Relying Customer Name (e.g., XYZ Co.)  
         [0131]     Subscribing Customer Name (e.g., ABC Co.)  
         [0132]     Subscribing Customer Employee (e.g., John Smith)  
         [0133]     Requested Attributes (indicating the attributes that are the subject of the authorization request)  
         [0134]     An exemplary XML implementation of a static authorization request to determine the type and value of items that John Smith is authorized to purchase (i.e., his purchasing authority and purchasing limit) may be as follows:  
         [0000]     &lt;AuthorizationRequestServiceNo 12345&gt; 
         [0135]     &lt;RequestType Type=“static”/&gt; 
         [0136]     &lt;RequestId Id=“00255501”/&gt; 
         [0137]     &lt;RCNameAndId Id=“123456” Name=“XYZ Co.”/&gt; 
         [0138]     &lt;SCNameAndId Id=“654321” Name=“ABC Co.”/&gt; 
         [0139]     &lt;SCEmployeeNameAndId Id=“13579” Name=“John Smith”&gt; 
         [0140]     &lt;RequestedAttributes Attributes=“Purchasing Authority, Purchasing Limit”/&gt; 
         [0000]     &lt;/AuthorizationRequestServiceNo 12345&gt; 
         [0141]     Continuing with  FIG. 4 , in step  417 , XYZ Co. signs the authorization request message and sends it to Bank B (message  7  in  FIG. 5 ). In step  418 , Bank B transmits the authorization request message to Bank A (message  8  in  FIG. 5 ).  
         [0142]     In step  419 , Bank A receives the request and checks its repository  270   IP  to determine whether or not it has the appropriate messaging specification data in order to generate a response to the authorization request. If Bank A has the appropriate messaging specification data, processing proceeds to step  427 , described below.  
         [0143]     Otherwise (which may occur, for example, if the authorization service that is the subject of the request was developed by a different system participant), then, in step  420 , Bank A generates a request for the appropriate response message format, signs the request, and sends the request to root entity  110  (message  9  in  FIG. 5 ).  
         [0144]     In step  421 , root entity  110  receives the request and retrieves from central repository  260  any applicable access-control implementation rules necessary to process the request. In step  422 , root entity  110  applies these rules to determine whether or not it will release the requested authorization-response message format to Bank A.  
         [0145]     If Bank A is not authorized to receive the requested message format, then, in step  423 , root entity  110  generates a rejection message indicating this fact, signs it, and transmits it to Bank A (message  10  in  FIG. 5 ). In step  424 , Bank A generates a message indicating that it cannot process the authorization request, signs it, and transmits it to Bank B (message  11  in  FIG. 5 ). In step  425 , Bank B transmits the message to XYZ Co., and processing ends (message  12  in  FIG. 5 ).  
         [0146]     Otherwise, in step  426 , root entity  110  retrieves from central repository  260  the requested authorization-response message format, creates a signed message that includes the requested message format, and transmits the message to Bank A (message  13  in  FIG. 5 ).  
         [0147]     In step  427 , Bank A retrieves from directory  270   IP  the appropriate credential record for the individual that is the subject of the authorization request (e.g., John Smith). In addition, Bank A retrieves from directory  270   IP  any necessary definition and mapping information for processing the request. Bank A uses this information to process the authorization request from XYZ Co.  
         [0148]     For example, if the authorization request seeks to determine whether John Smith is authorized to purchase $200 of adhesive tape, Bank A reviews John Smith&#39;s purchasing authority attributes (and any necessary related definition or mapping information) and his purchasing limit, and determines (on these facts) that John Smith is authorized to conduct the transaction.  
         [0149]     It should be noted that, in the present exemplary embodiment, it is assumed that the purchasing limit attribute assigned to John Smith is a per-transaction limit. It will be recognized that subscribing customer  106  may alternatively or in addition assign to its employees time-based (e.g., monthly) or other purchasing limits. If, for example, John Smith was also assigned a monthly limit, Bank A would preferably track all purchases made by John Smith and maintain a running total of those purchases during the last month. Upon receipt of an authorization request for a specified transaction amount, Bank A would add this transaction amount to John Smith&#39;s running total for the month, compare the sum to John Smith&#39;s monthly purchasing limit, and issue a positive authorization only if the sum did not exceed the monthly purchasing limit.  
         [0150]     In step  428 , Bank A uses the authorization-response message format to generate an appropriate response to XYZ Co.&#39;s authorization request. Continuing with the exemplary embodiment, a response to the dynamic authorization request described above may include the following fields:  
         [0151]     Authorization Response Message Code (indicating that the message is an authorization response message and specifying a particular authorization service by number)  
         [0152]     Request ID  
         [0153]     Response (Boolean value such as Authorized or Not Authorized)  
         [0154]     An exemplary XML implementation of the above response may be as follows:  
         [0000]     &lt;AuthorizationResponseServiceNo 12345&gt; 
         [0155]     &lt;RequestId Id=“0034201”/&gt; 
         [0156]     &lt;Response&gt;Authorized&lt;/Response&gt; 
         [0000]     &lt;/AuthorizationResponseServiceNo 12345&gt; 
         [0157]     A response to the static authorization request described above may include the following fields:  
         [0158]     Authorization Response Message Code (indicating that the message is an authorization response message and specifying a particular authorization service by number)  
         [0159]     Request ID  
         [0160]     Credential Record  
         [0161]     An exemplary XML implementation for such a response message may be:  
         [0000]     &lt;AuthorizationResponseServiceNo 12345&gt; 
         [0162]     &lt;RequestId Id=“0034201”/&gt; 
         [0163]     &lt;EmployeeName&gt;John Smith&lt;/EmployeeName&gt; 
         [0164]     &lt;EmployeeTitle&gt;Office Manager&lt;/EmployeeTitle&gt; 
         [0165]     &lt;PurchasingAuthority&gt;Office Supplies&lt;/PurchasingAuthority&gt; 
         [0166]     &lt;PurchasingLimit Currency=“USD”&gt;75,000&lt;/PurchasingLimit&gt; 
         [0000]     &lt;/AuthorizationResponseServiceNo 12345&gt; 
         [0167]     In step  429 , Bank A signs the authorization response message and sends it to Bank B (message  14  in  FIG. 5 ). In step  430 , Bank B transmits the authorization response message to XYZ Co. (message  15  in  FIG. 5 ). If the authorization response is satisfactory to XYZ Co., then, in step  431 , XYZ Co. sends a confirmation message for the transaction to John Smith at ABC Co. Otherwise, if the authorization response is not satisfactory to XYZ Co., then, in step  432 , XYZ Co. may send a message to John Smith at ABC Co. disaffirming the transaction.  
         [0000]     Process Flow for Bundled Authorization Service and Certificate Validation or Other System Services  
         [0168]     In a preferred embodiment, an authorization request by a relying customer  108  may preferably be bundled and processed concurrently with a request for another system service such as certificate validation. Preferred embodiments for validating a subscribing customer  106 &#39;s certificate are described, for example, in copending U.S. application Ser. No. 09/657,605, filed Sep. 8, 2000, entitled System and Method for Certificate Validation and Other Services, which is hereby incorporated by reference. A summarized version of that certificate validation process is described below in connection with the bundled authorization/certificate validation services. This preferred embodiment is now described in connection with  FIGS. 6-7 .  
         [0169]     Beginning with  FIG. 6 , in step  601 , subscribing customer  106  visits relying customer  108 &#39;s Web site. The parties preferably authenticate themselves to each other over an SSL session with their utility keys.  
         [0170]     In step  602 , Web server  220  communicates data to be digitally signed to browser  224  (e.g., a purchase order for an agreed-to transaction). In step  603 , the data to be signed is forwarded to smartcard subsystem  226  which signs the data to create a digitally-signed document. In step  604 , browser  224  receives the digitally-signed document and transmits it to Web server  220  or another appropriate location specified by relying customer  108 . In a preferred embodiment, this signing process may be facilitated by using a signing interface  225  to invoke smartcard subsystem  226 , as described in U.S. provisional application Ser. No. 60/224,994, filed Sep. 8, 2000, entitled Signing Interface Requirements, Smart Card Compliance Requirements, Warranty Service Functional Requirements, and Additional Disclosure, which is hereby incorporated by reference.  
         [0171]     In step  605 , relying customer  108  receives the digitally-signed document. In step  606 , relying customer  108  generates an authorization request message in accordance with steps  407 - 416 , as described above. In step  607 , relying customer  108  creates an OCSP request for subscribing customer  106 &#39;s digital certificate. In step  608 , relying customer  108  concatenates the two requests and signs the resulting message. In a preferred embodiment, the messaging specification for the authorization service may include a single request that seeks both authorization and certificate validation. In step  609 , relying customer  108  transmits the request(s) to relying participant  104  (message  1  in  FIG. 7 ).  
         [0172]     In step  610 , relying participant  104  identifies the issuing participant that issued the digital certificate that is the subject of the OCSP request and, in step  611 , transmits the request to that participant (i.e., issuing participant  102  in the present example) (message  2  in  FIG. 7 ).  
         [0173]     In step  612 , issuing participant  102  processes the authorization request in accordance with steps  419 - 428  as described above. In step  613 , issuing participant creates an OCSP response for the validation request using its OCSP responder  204   IP . In step  614 , issuing participant  102  concatenates the authorization response message and OCSP response and signs the resulting message. In a preferred embodiment, the messaging specification for the authorization service may include a single response message for responding to a bundled authorization/certificate validation request.  
         [0174]     In step  615 , issuing participant  102  transmits the response(s) to relying participant  104  (message  3  in  FIG. 7 ). In step  616 , relying participant  104  transmits the response(s) to relying customer  108  (message  4  in  FIG. 7 ). In step  617 , relying customer  108  reviews the response(s). If the authorization and validation responses are satisfactory to relying customer  104 , then, in step  618 , XYZ Co. sends a confirmation message for the transaction to subscribing customer  106 . Otherwise, if one or more of the service responses are not satisfactory to relying customer  108 , then, in step  619 , relying customer  108  may send a message to subscribing customer  106  disaffirming the transaction.  
         [0175]     It will be recognized that, in other preferred embodiments, system services other than certificate validation may be processed concurrently with the authorization service. These system services may, for example, include a warranty service.  
         [0176]     It should be noted that, in a preferred embodiment, all inter-entity messages transmitted and received by participants  102 ,  104 , and root entity  110  may be routed through an appropriate system component adapted for such processing, such as, for example, transaction coordinator  202 .  
         [0177]     It should be noted that although the preferred embodiments described above speak primarily in terms of a transaction conducted by an individual employee of subscribing customer  106 , the transaction may alternatively be automatically conducted by an appropriate server maintained by subscriber customer  106 . In that case, relying customer  108  may, for example, seek an authorization that the subscribing customer will stand behind a transaction conducted with the server.  
         [0178]     It should also be recognized that although in the preferred embodiments described above subscribing customer  106  and issuing participant  102  work together to design a desired authorization service, in an alternative preferred embodiment, issuing participant  102  (or other entities such as root entity  110 ) may design in advance one or more authorization services and seek approval from the policy management authority for them. Once approved, these may serve as “off-the-shelf” authorization services that may be offered to a subscribing customer  106 . In particular, it may be desirable to design and seek approval for industry-specific authorization services that an issuing participant expects will be popular with its customers.  
         [0179]     While the invention has been described in conjunction with specific embodiments, it is evident that numerous alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description.