Abstract:
In a pay-per-use computer environment, particularly when network access is limited, self-monitoring tools on a pay-per-use computer may require special support from a host/server. The host/server must be able to respond to requests quickly and efficiently and yet maintain full information required to service requests and updates. A key management table and a device management table provide critical information required to service requests. Use of SQL notifications allows local database caches to remain current but quickly accessible.

Description:
BACKGROUND  
       [0001]    Pay-as-you-go or pay-per-use business models have been used in many areas of commerce, from cellular telephones to commercial laundromats. In developing a pay-as-you go business, a provider, for example, a cellular telephone provider, offers the use of hardware (a cellular telephone) at a lower-than-market cost in exchange for a commitment to remain a subscriber to their network for a period of time. In this specific example, the customer receives a cellular phone for little or no money in exchange for signing a contract to become a subscriber for a given period of time. Over the course of the contract, the service provider recovers the cost of the hardware by charging the consumer for using the cellular phone. 
         [0002]    In the case of the cellular telephone, all charges are billed, mediated, and accrued on the network side. Even a pre-paid user account has value, in terms of minutes or text messages, stored on the network and a local SIM card for identifying the phone/account to the network. Because the phone is essentially useless unless connected to the network, the model works. 
         [0003]    However, unlike a cellular telephone, a pay-per-use computer may have substantial value to a user even though only occasionally connected to a network. Therefore, the computer must be able to meter and monitor its own operation with only infrequent access to a network host. While potential lack of access places a significant security burden on the computer to fairly meter usage, it also requires special consideration at the network end. Because a network server and the pay-per-use computer may only have occasional, and sometimes brief contact with each other, the network server must be able to respond quickly and correctly to requests from the computer. Likewise, requests from customer service or a repair facility must be coordinated so that correct information is available in a timely manner. Underlying all communication and metered-use activity is a security core based on cryptographic principals which brings its own requirements. 
       SUMMARY  
       [0004]    This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. 
         [0005]    A web portal supporting a pay-per-use computer business model and an underlying database may use tailored schemas to support such tasks as request processing and key management. The portal schema may include a device schema with a request table and a key management schema that supports a number of tables corresponding to cryptographic requirements for specific portions of the product life cycle such as a manufacturer table and an account table. A local cache of system data relating to devices and key management may be used for speed and security reasons. The local cache may use a SQL notification service to maintain data of interest in the local cache, even when a request is not being processed. The SQL notification service keeps a list of data maintained in a local cache and sends a notification to the local cache when any of the locally-maintained data elements change. The local cache system may then update the data as required. Because the local cache is fresh, requests may be processed locally without waiting for a data verification check. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0006]      FIG. 1  is a simplified and representative block diagram of a system supporting a pay-as-you-go business model; 
           [0007]      FIG. 2  is a simplified and representative block diagram of a provisioning server of  FIG. 1 ; 
           [0008]      FIG. 3  is an exemplary device schema; 
           [0009]      FIG. 4A  is a first portion of an exemplary key management schema; 
           [0010]      FIG. 4B  is second portion of an exemplary key management schema; 
           [0011]      FIG. 4C  is a third portion of an exemplary key management schema; and 
           [0012]      FIG. 5  is a method of operating a pay-per-use computer system portal. 
       
    
    
     DETAILED DESCRIPTION  
       [0013]    Although the following text sets forth a detailed description of numerous different embodiments, it should be understood that the legal scope of the description is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims. 
         [0014]    It should also be understood that, unless a term is expressly defined in this patent using the sentence “As used herein, the term ‘______’ is hereby defined to mean . . . ” or a similar sentence, there is no intent to limit the meaning of that term, either expressly or by implication, beyond its plain or ordinary meaning, and such term should not be interpreted to be limited in scope based on any statement made in any section of this patent (other than the language of the claims). To the extent that any term recited in the claims at the end of this patent is referred to in this patent in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term by limited, by implication or otherwise, to that single meaning. Finally, unless a claim element is defined by reciting the word “means” and a function without the recital of any structure, it is not intended that the scope of any claim element be interpreted based on the application of 35 U.S.C. §112, sixth paragraph. 
         [0015]    Much of the inventive functionality and many of the inventive principles are best implemented with or in software programs or instructions and integrated circuits (ICs) such as application specific ICs. It is expected that one of ordinary skill, notwithstanding possibly significant effort and many design choices motivated by, for example, available time, current technology, and economic considerations, when guided by the concepts and principles disclosed herein will be readily capable of generating such software instructions and programs and ICs with minimal experimentation. Therefore, in the interest of brevity and minimization of any risk of obscuring the principles and concepts in accordance to the present invention, further discussion of such software and ICs, if any, will be limited to the essentials with respect to the principles and concepts of the preferred embodiments. 
         [0016]      FIG. 1  illustrates a representative system  200  supporting a pay-per-use business model. A provisioning server  202  may be coupled to an accounting server  210  where account balances may be maintained, as well as connections to individual subscriber&#39;s funding accounts (not depicted), when used. A network  208 , such as the Internet may couple the provisioning server  202  to one or more electronic devices  204 ,  206 . The link between the provisioning server  202  and the accounting server  210  and related sites, may also be via the network  208 . The electronic devices  204 ,  206 , may be pay-per-use or metered-use computers, that is, the electronic devices may be self-monitoring and self-enforcing devices, capable of managing one or more usage mode, such as prepaid use using locally stored value. The operation modes may include metered use, that is, local payment made according to a metric such as time duration or resource use (e.g. cpu cycles). Other modes may include subscription use with use allowed until an expiration date/time. Other modes, or combinations of these may also be supported. Postpaid usage may also be supported in some business models, with the value of use accumulated and settled during periodic connection to the provisioning server  202 . In each case, communication with the provisioning server  202  may be occasional, at best, although a minimum level of communication may be mandated. 
         [0017]    Should the electronic device  204 ,  206  wish to continue operation, connection to the provisioning server may be initiated and a request for additional usage forwarded. Time synchronization may be required to help prevent fraudulent subscription or metering use caused by local clock manipulation. The electronic device  204 ,  206  may also include a protected subsystem to manage metering, stored value, and policy enforcement. The latter being the ability of the electronic device  204 ,  206  to place itself in a limited operation mode when terms of use are not satisfied, such as low local stored value, or detection of tampering. 
         [0018]    The provisioning server  202  may also be coupled to a customer service server  212  that may support one or more customer service representatives or even a web-based support feature (not depicted). A database  214  run from the provisioning server may maintain local data, such as information about the status of downloads to the one or more electronic devices  204 ,  206 , but may also include cached data from the accounting server  210 , the customer service server  212 , or both. 
         [0019]    Turning briefly to  FIG. 2 , an exemplary block diagram of a server  300 , similar to the provisioning server  202  of  FIG. 1  is discussed and described. The provisioning server  300  may include a processor  302  and a communication port  304  for communication over network link  306 . The provisioning server  300  may also include memory  310 . The memory  310  may be any combination of volatile and non-volatile memory, such as random access memory (RAM), read-only memory (ROM), rotating media, flash memory, etc. The memory  310  may be used by the processor to store settings and use for intermediate results. The memory  310  may also be used to store computer-executable instructions that may include executable program modules for communication  314 , key management  316 , device management  318 , and time keeping  320 . 
         [0020]    The key and device management functions  316 ,  318  are discussed in more detail below, but briefly, may be executed as required for building and using the key and device schemas for the administration of the pay-per-use computers. 
         [0021]    The provisioning server  300  may also include a clock  322  for use with the time keeping module  320  for subscription management and time-based metering. A cryptographic function  308  may be used to support a variety of security purposes, including message authentication, encryption, and public key infrastructure (PKI) support. 
         [0022]    Returning to  FIG. 1 , in operation, one of the electronic devices  204  may require service, either upon initial installation or as a result of a request to add more usage time. The request may be forwarded to the provisioning server  202  and the database  214  may be checked for current status using a request table from the device schema. The database, even though largely a mirror of data sourced from other systems, for example, the accounting  210  or customer service  212  servers may be kept up to date via a SQL notification process that notifies the database  214  when information on in the source changes. 
         [0023]    The provisioning server may create an packet for transmission to the electronic device  204  after processing the request, for example, by debiting funds from a user account. The provisioning server  202  may be required to send the data for signing. While in the signature process, the database may also query and update a key management schema to extract appropriate keys qualifying the data in the packet. In one embodiment, keys may be based on a combination of underwriter identity, the identity of the electronic device  204 , and the pay-per-use options contracted for that electronic device  204 . The key management schema may allow direct generation of the required keys, or may send indexes to an external cryptographic function, such as a hardware security module for packet signing. The key management schema may update elements, such as any rolling codes used in the system  200 . 
         [0024]    After the packet has been created and signed, the provisioning server  202  may deliver the packet to the electronic device  204 . Delivery confirmation may be tracked and re-tries processed as required, up to a non-delivery limit. After confirmation of delivery, the device schema may be updated to reflect the most recent transaction. 
         [0025]      FIG. 3  illustrates an exemplary device schema  300 . The device schema  300  may include a request table  302  and a device table  304 . The request table  302  may include various fields summarized in Table 1 below. Reference numbers to  FIG. 3  are shown in parentheses ( ), exemplary field widths are in braces [ ]. 
         [0000]    
       
         
               
             
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Request Table (302, FIG. 3) 
               
             
          
           
               
                   
                   
                 Allow 
                   
               
               
                 Column Name 
                 Data Type 
                 Null 
                 Description 
               
               
                   
               
               
                 RequestId (306) 
                 int 
                 No 
                 Primary key. Automatically generated. 
               
               
                 ParentRequestId 
                 int 
                 Yes 
                 If child of BatchRequest, this contains 
               
               
                 (308) 
                   
                   
                 the parent batch Id. 
               
               
                 TrackingId (310) 
                 Nvarchar[50] 
                 No 
                 Universally unique identifier of the 
               
               
                   
                   
                   
                 batch request. Note it is different from 
               
               
                   
                   
                   
                 the BatchId. 
               
               
                 PartnerCode 
                 Nchar[5] 
                 No 
                 The Partner Code assigned to the 
               
               
                 (312) 
                   
                   
                 partner by the scheme owner. 
               
               
                 Hwid (314) 
                 Nvarchar[46] 
                 Yes 
                 Hardware_Id identifying the client 
               
               
                   
                   
                   
                 device. 
               
               
                 V1DeviceId 
                 Int 
                 Yes 
                 If a legacy device, index into the legacy 
               
               
                 (316) 
                   
                   
                 device table. 
               
               
                 Type (318) 
                 int 
                 No 
                 Identifies the type of request. 
               
               
                   
                   
                   
                 Request types may include 
               
               
                   
                   
                   
                 ProvisionDevice, HLMUnlock, 
               
               
                   
                   
                   
                 PerpetuateDevice, etc. 
               
               
                 Mode (320) 
                 Int 
                 No 
                 Identifies whether this is a CSR 
               
               
                   
                   
                   
                 operation or a Batch operation. 
               
               
                 Status (322) 
                 int 
                 No 
                 The status for the batch. It must be in 
               
               
                   
                   
                   
                 one of the following state: 
               
             
          
           
               
                   
                   
                   
                 1. 
                 New: the batch is created and not 
               
               
                   
                   
                   
                   
                 sent. 
               
               
                   
                   
                   
                 2. 
                 Sent: the batch is sent to and 
               
               
                   
                   
                   
                   
                 acknowledged by the server and no 
               
               
                   
                   
                   
                   
                 BatchResponse received yet. 
               
               
                   
                   
                   
                 3. 
                 Succeed: BatchResponse received 
               
               
                   
                   
                   
                   
                 and all requests in the batch are 
               
               
                   
                   
                   
                   
                 handled successfully. 
               
               
                   
                   
                   
                 4. 
                 Failed: BatchResponse received 
               
               
                   
                   
                   
                   
                 and one or more requests in the 
               
               
                   
                   
                   
                   
                 batch are failed. 
               
               
                   
                   
                   
                 5. 
                 SendFailed: There was an error 
               
               
                   
                   
                   
                   
                 processing the request before 
               
               
                   
                   
                   
                   
                 sending to server. The request 
               
               
                   
                   
                   
                   
                 failed. 
               
               
                   
                   
                   
                 6. 
                 Pending: the batch is pending 
               
               
                   
                   
                   
                   
                 processing at the server. 
               
             
          
           
               
                   
                   
                   
                 Since this table stores batch as well as 
               
               
                   
                   
                   
                 individual request information, this also 
               
               
                   
                   
                   
                 stores statuses of individual requests. 
               
               
                   
                   
                   
                 The individual request statuses map 
               
               
                   
                   
                   
                 directly to those received from the 
               
               
                   
                   
                   
                 server. 
               
               
                 Request (322) 
                 Xml 
                 No 
                 Actual Request XML that was sent 
               
               
                 Response (324) 
                 Nvarchar[500] 
                 Yes 
                 Response received from the server 
               
               
                 ErrorCode (328) 
                 Int 
                 No 
                 Stores errorCode information if any that 
               
               
                   
                   
                   
                 is associated with this request. 
               
               
                 TransactionId 
                 Nchar[25] 
                 Yes 
                 Metadata associated with transaction 
               
               
                 (330) 
               
               
                 TimeSent (332) 
                 Datetime 
                 No 
                 The time when the batch is sent 
               
               
                   
                   
                   
                 successfully to the server. This is used 
               
               
                   
                   
                   
                 to sort the bulk operation history. 
               
               
                 TimeLastUpdated 
                 Datetime 
                 Yes 
                 The time when the batch is updated 
               
               
                 (334) 
                   
                   
                 with the latest batch response. 
               
               
                 Reason (336) 
                 Nvarchar[512] 
                 Yes 
                 Reason metadata associated with batch 
               
               
                   
                   
                   
                 or request. Reasons may include initial 
               
               
                   
                   
                   
                 load, update clock, adjustments for 
               
               
                   
                   
                   
                 customer satisfaction, purchase of time, 
               
               
                   
                   
                   
                 etc. 
               
               
                   
               
             
          
         
       
     
         [0026]    Batch operations may include those requested by a manufacturer, such as initializing a set of new electronic devices. Individual requests may include requests for additional usage time, clock verification, and reconfiguration. 
         [0027]    Legacy operations with devices from prior versions may require additional data for compatibility. The device table  304  may include those fields. A representative device table is illustrated in Table 2. 
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 DeviceV1 Table (304) 
               
             
          
           
               
                   
                   
                 Allow 
                   
               
               
                 Column Name 
                 Data Type 
                 Null 
                 Description 
               
               
                   
               
               
                 DeviceId (338) 
                 int 
                 No 
                 Primary key. Automatically 
               
               
                   
                   
                   
                 generated. 
               
               
                 ProductKeyHash 
                 bigint 
                 Yes 
                 The double hashed Windows 
               
               
                 (334) 
                   
                   
                 product key associated with 
               
               
                   
                   
                   
                 the legacy device. 
               
               
                 DeviceName 
                 Nvarchar[50] 
                 Yes 
                 Unique DeviceName to 
               
               
                 (336) 
                   
                   
                 identify the legacy device. 
               
               
                   
               
             
          
         
       
     
         [0028]      FIG. 4A  is a portion of a representative key management schema  400 . The key management schema may include one or more of the following tables, or their functional equivalents: an account table  402  a role_account table  404 , and a role table  406 . Each of the tables and representative fields are shown and described in Tables 3-5. As above, reference designators corresponding to  FIG. 4A  are in parenthesis ( ), representative field widths, when appropriate, are in braces [ ]. 
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 RoleAccount Table (404, FIG. 4A) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 RoleId (410) 
                 int 
                 No 
                 Primary Key; Role Idenifier of 
               
               
                   
                   
                   
                 associated table for many to 
               
               
                   
                   
                   
                 many relationships. 
               
               
                 AccountId 
                 Int 
                 No 
                 Primary Key; Account identifier 
               
               
                 (411) 
                   
                   
                 of associated table for many to 
               
               
                   
                   
                   
                 many relationships. 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 4 
               
             
             
               
                   
               
               
                 Account Table (402) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (407) 
                 int 
                 No 
                 Primary Key; 
               
               
                   
                   
                   
                 Automatically generated. 
               
               
                 Name (408) 
                 Nvarchar[50] 
                 No 
                 Name of Windows account 
               
               
                   
                   
                   
                 that service or tool 
               
               
                   
                   
                   
                 impersonates. 
               
               
                 Description 
                 Nvarchar[256] 
                 Yes 
                 Description about the 
               
               
                 (409) 
                   
                   
                 Account. 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 5 
               
             
             
               
                   
               
               
                 Role Table (406) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (412) 
                 int 
                 No 
                 Primary Key; 
               
               
                   
                   
                   
                 Automatically generated. 
               
               
                 Name (413) 
                 Nvarchar[50] 
                 No 
                 Name of Role; 
               
               
                   
                   
                   
                 CoreService | Distribution | 
               
               
                   
                   
                   
                 Customer service | Key 
               
               
                   
                   
                   
                 Generation 
               
               
                 Rights (414) 
                 Int 
                 No 
                 Rights to invoke Key 
               
               
                   
                   
                   
                 Management Service 
               
               
                   
                   
                   
                 interface methods expressed 
               
               
                   
                   
                   
                 as bit map. 
               
               
                 Description 
                 Nvarchar[256] 
                 Yes 
                 Description about the 
               
               
                 (415) 
                   
                   
                 Role. 
               
               
                   
               
             
          
         
       
     
         [0029]      FIG. 4B  is a portion of a representative key management schema  420 . The key management schema may include one or more of the following tables, or their functional equivalents: an enumeration table  422 , a lock mode table  424 , a key table  426 . Each of the tables and representative fields are shown and described in Tables 6-8. As above, reference designators corresponding to  FIG. 4B  are in parenthesis ( ), representative field widths are in braces [ ]. 
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 6 
               
             
             
               
                   
               
               
                 Enumeration Table (422, FIG. 4B) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 EnumId (427) 
                 Int 
                 No 
                 Primary key, it is the 
               
               
                   
                   
                   
                 number of the enumeration 
               
               
                   
                   
                   
                 value. It is unique crossing 
               
               
                   
                   
                   
                 all of the enumeration 
               
               
                   
                   
                   
                 types. 
               
               
                 Type (428) 
                 nvarchar[25] 
                 No 
                 The enumeration type 
               
               
                   
                   
                   
                 such as KeyStatus, 
               
               
                   
                   
                   
                 DeviceStatus. 
               
               
                 Name (429) 
                 nvarchar[50] 
                 No 
                 The name of the 
               
               
                   
                   
                   
                 enumeration value. 
               
               
                 Description 
                 Nvarchar[256] 
                 Yes 
                 Brief description of 
               
               
                 (430) 
                   
                   
                 the enumeration value. 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 7 
               
             
             
               
                   
               
               
                 HLMKey Table (424) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (431) 
                 Bigint 
                 No 
                 Primary Key; Automatically generated. 
               
               
                 PartnerCode (432) 
                 Nchar[5] 
                 No 
                 Code that uniquely identifies the Partner. 
               
               
                 PartnerName 
                 Nvarchar[50] 
                 No 
                 Name of the partner. 
               
               
                 (433) 
               
               
                 PrivateKey (434) 
                 varbinary[MAX] 
                 No 
                 Lock mode Private key stored as encrypted blob. 
               
               
                 PublicKey (435) 
                 varbinary[MAX] 
                 No 
                 Lock mode Public key stored as encrypted blob. 
               
               
                 Status (436) 
                 Int 
                 No 
                 Status of the Lock Mode Key - Active | Inactive 
               
               
                   
                   
                   
                 Need to enforce only one Active Lock Mode Key 
               
               
                   
                   
                   
                 per partner. 
               
               
                 Description (437) 
                 Nvarchar[256] 
                 Yes 
                 Description about the Lock Mode Key. 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 8 
               
             
             
               
                   
               
               
                 Key Table (426) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 KeyId (438) 
                 Int 
                 No 
                 Primary Key; 
               
               
                   
                   
                   
                 Automatically generated. 
               
               
                 KeyData (439) 
                 varbinary[MAX] 
                 No 
                 Master Key as encrypted 
               
               
                   
                   
                   
                 string. 
               
               
                 KeyHash (440) 
                 Binary[32] 
                 No 
                 SHA 256 hash of 
               
               
                   
                   
                   
                 Master Key [without 
               
               
                   
                   
                   
                 encryption]. Since 
               
               
                   
                   
                   
                 UNIQUE constraint 
               
               
                   
                   
                   
                 cannot be applied to 
               
               
                   
                   
                   
                 KeyData column, 
               
               
                   
                   
                   
                 UNIQUE constraint 
               
               
                   
                   
                   
                 is applied on this 
               
               
                   
                   
                   
                 column. 
               
               
                 Status (441) 
                 Int 
                 No 
                 Status of the Key - In 
               
               
                   
                   
                   
                 Use; Deprecated 
               
               
                   
               
             
          
         
       
     
         [0030]      FIG. 4C  is a portion of a representative key management schema  460 . The key management schema may include one or more of the following tables, or their functional equivalents: a device table  462 , a batch table  464 , and a manufacturer table  466 . Each of the tables and representative fields are shown and described in Tables 9-11. As above, reference designators corresponding to  FIG. 4C  are in parenthesis ( ),representative field widths are in braces [ ]. 
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 9 
               
             
             
               
                   
               
               
                 Device Table (462, FIG. 4C) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 DeviceId (467) 
                 Bigint 
                 No 
                 Primary Key; Automatically generated. 
               
               
                 Hwid (468) 
                 Bigint 
                 No 
                 Unique hardware identifier built in device module. 
               
               
                   
                   
                   
                 It must be unique in the table. It is 64 bit data with 
               
               
                   
                   
                   
                 the following format: 
               
               
                   
                   
                   
                 Platform data - 8 bits 
               
               
                   
                   
                   
                 Version Info (Metadata ID) - 8 bits 
               
               
                   
                   
                   
                 Test/Production - 1 bit 
               
               
                   
                   
                   
                 Reserved - 4 bits 
               
               
                   
                   
                   
                 Assigned Portion - 48 bits 
               
               
                 ManufacturerId 
                 Int 
                 No 
                 Manufacturer identifier; Foreign key connecting to 
               
               
                 (469) 
                   
                   
                 Manufacturer table. 
               
               
                 BatchId (470) 
                 Int 
                 No 
                 Batch identifier Foreign Key connecting to Batch 
               
               
                   
                   
                   
                 table. 
               
               
                 Status (471) 
                 Int 
                 No 
                 Status of the device - Created | Registered 
               
               
                 UpdateTime (472) 
                 Datetime 
                 No 
                 Timestamp at which device info is updated. 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 10 
               
             
             
               
                   
               
               
                 Batch Table (464) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (473) 
                 bigint 
                 No 
                 Primary Key; Automatically generated. 
               
               
                 ManufacturerId 
                 int 
                 No 
                 Manufacturer identifier; Foreign key connecting to 
               
               
                 (474) 
                   
                   
                 Manufacturer table. 
               
               
                 BatchGUID (475) 
                 int 
                 No 
                 Batch global unique identifier. 
               
               
                 UserName (476) 
                 nvarchar[50] 
                 No 
                 Windows Security principal name of user that 
               
               
                   
                   
                   
                 added this entry, for auditing purposes. 
               
               
                 Size (477) 
                 Int 
                 No 
                 Size of the batch; Total number of hardware 
               
               
                   
                   
                   
                 identifiers and Key data to generate. 
               
               
                 Status (478) 
                 int 
                 No 
                 Status of the device - Created; Registered 
               
               
                 Description (479) 
                 Nvarchar[MAX] 
                 Yes 
                 Description of the batch operation. Subsequent 
               
               
                   
                   
                   
                 task details on the same batch get appended to 
               
               
                   
                   
                   
                 provide the history of tasks. 
               
               
                 CreationTime 
                 datetime 
                 No 
                 Timestamp at which Batch is created. 
               
               
                 (480) 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 11 
               
             
             
               
                   
               
               
                 Manufacturer Table (466) 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (481) 
                 Int 
                 No 
                 Primary Key; Automatically generated. 
               
               
                 Name (482) 
                 Nvarchar[50] 
                 No 
                 Name of manufacturer. Server owner is also 
               
               
                   
                   
                   
                 added as one partner to support varying 
               
               
                   
                   
                   
                 requirements from chip manufacturers. 
               
               
                 SharedKey (483) 
                 Variable length 
                 No 
                 Shared key issued to every manufacturer. It is 
               
               
                   
                 binary[MAX] 
                   
                 used to transfer the device symmetric keys - 
               
               
                   
                   
                   
                 Hardware identifier data file encrypted with this 
               
               
                   
                   
                   
                 shared key. 
               
               
                 Status (484) 
                 int 
                 No 
                 Status of the manufacturer - Active; Disabled 
               
               
                 Description (485) 
                 Nvarchar[256] 
                 Yes 
                 Description of the manufacturer. 
               
               
                   
               
             
          
         
       
     
         [0031]      FIG. 4D  is an additional portion of a representative key management schema  460 . The key management schema may include one or more of the following tables, or their functional equivalents: a metadata table  604 , a platform table  602 , and a KeyMetadata table  606 . Each of the tables and representative fields are shown and described in Tables 12-14. As above, reference designators corresponding to  FIG. 4C  are in parenthesis ( ), representative field widths are in braces [ ]. 
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 12 
               
             
             
               
                   
               
               
                 Metadata Table (604, FIG. 4D) 
               
               
                 The metadata is used for versioning the devices and this is 
               
               
                 added to the highest order bit in the hwid. 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (624) 
                 int 
                 No 
                 PrimaryKey: This is 
               
               
                   
                   
                   
                 the versioning 
               
               
                   
                   
                   
                 information added 
               
               
                   
                   
                   
                 to the highest 
               
               
                   
                   
                   
                 order byte of the hwid 
               
               
                 KeyMetaDataId 
                 Int 
                 No 
                 The key set to be used 
               
               
                 (626) 
                   
                   
                 for this version 
               
               
                 EncAlg (628) 
                 NVARCHAR[10] 
                 No 
                 This field is reserved 
               
               
                 Status (630) 
                 NVARCHR[10] 
                 No 
                 This field is reserved 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 13 
               
             
             
               
                   
               
               
                 Platform Table (602) 
               
               
                 The Platform table is used to define the platform of the hardware. 
               
               
                 This is mainly for informational purposes and key management uses 
               
               
                 this for mapping the metadata Id alone for that platform. This metadataId 
               
               
                 associated with a platform can be changed at any time. This is 
               
               
                 inserted into the first four bits of the second highest order bits 
               
               
                 of the hwid. 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (612) 
                 int 
                 No 
                 PrimaryKey: This 
               
               
                   
                   
                   
                 is the identifier and 
               
               
                   
                   
                   
                 is inserted into the 
               
               
                   
                   
                   
                 hwid 
               
               
                 MetaDataId (614) 
                 Int 
                 No 
                 The versioning 
               
               
                   
                   
                   
                 associated with 
               
               
                   
                   
                   
                 the platform 
               
               
                 Name (616) 
                 NVARCHAR[50] 
                 No 
                 The name of the 
               
               
                   
                   
                   
                 platform 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 14 
               
             
             
               
                   
               
               
                 KeyMetadata Table (608) 
               
               
                 This table enables grouping of the keys into sets of keys and 
               
               
                 defines the maximum number of keys that are allowed for the set 
               
               
                 of keys and the number of used keys from the set of keys. 
               
             
          
           
               
                 Column Name 
                 Data Type 
                 Nullable 
                 Description 
               
               
                   
               
               
                 Id (640) 
                 int 
                 No 
                 Primary Key 
               
               
                 Description 
                 NVARCHAR[50] 
                 No 
                 A description of the 
               
               
                 (642) 
                   
                   
                 set of keys 
               
               
                 MaxKeys (644) 
                 Int 
                 No 
                 The group hash modulus 
               
               
                   
                   
                   
                 used for the keys 
               
               
                 UsedKeys 
                 int 
                 No 
                 The number of keys from 
               
               
                 (646) 
                   
                   
                 the sequential set of 
               
               
                   
                   
                   
                 keys to be used. 
               
               
                   
               
             
          
         
       
     
         [0032]      FIG. 5  illustrates an exemplary method  500  of using portal and database schemas in the operation of a pay-per-use computer system portal. The portal and key management schemas allow fast and secure responses to be developed for requests relating to target pay-per-use devices, whether the request is initiated by customer service, the scheme owner, or the pay-per-use device itself. For both speed and security reasons, it is useful to use a local cache of the pay-per-use database information when generating responses. A capability known as SQL notification can be used to maintain fresh data in a local cache so that delays related to refreshing the cache are minimized. 
         [0033]    At block  502 , a database may be built using portal and key management schemas to support portal activity related pay-per-use computers. Individual instances of the schema may be created for each pay-per-use device and each host device, as needed. The portal schema may include a first device table and a request table, a request ID field as a key index, and a partner code defining a supplier of the pay-per-use computer. Building the portal schema may also include building the first device table to include a status field corresponding to one of a batch and an individual request, the status field having a value being one of new, sent, succeed, failed, send_failed, and pending. 
         [0034]    Building the key management schema may include generating a number of related tables corresponding to secure management of data and communications for the scheme owner, supplier partners, distribution channel partners, maintenance partners, and end-user devices. The key management schema may include a key table, a second device table, an enumeration table and a manufacturer table. Building the key management schema may also include building the key table to include a primary index field, a master key field, a key hash field, and a key status field. The key management schema may also include a second device table to include a device index field, a hardware identifier field, a first manufacturer index field, and a device status field. Building the key management schema may further include building the manufacturer table to include a shared key field, a manufacturer status field, and a second manufacturer index field linked to the first manufacturer index field of the second device table. Building the key management schema may include building the enumeration table to include an enumeration index field and a type field supporting key status or device status, and an enumeration value field. 
         [0035]    A block  504 , a request may be received for a specific action related to a pay-per-use computer. The request may include registration requests from a channel partner, may include a usage time adjustment request from a customer service representative, or may include a time synchronization request or a add-time request. The portal may be a web site supporting web services for receiving and responding to the request. The request, in one embodiment, may be an XML (extensible markup language) format request that corresponds to the pay-per-use or metered-use computer. The request may include device data, key data, or both. 
         [0036]    When the request is from a customer service source, the request may include metadata related to the reason for the request, such as, an adjustment due to a recent payment or for customer satisfaction, or a change in subscription terms. 
         [0037]    At block  506 , the request may be assigned an identifier and data in the request parsed according to pre-determined criteria, such as an Extensible Stylesheet Language (XSL) definition. Parsing the request may include determining a partner identifier, determining a hardware identifier, and determining when the request corresponds to a single electronic device or if the request is a child of a related batch request. 
         [0038]    At block  508 , the portal schema may be updated, including updating or creating table entries corresponding to the request. For example, in one embodiment, a request table may be populated with data from the request, including the assigned identifier and a related parent request, when appropriate. The request table may be further populated with a tracking identifier and a partner code, if the request is related to a supplier of hardware or software available at the electronic device, while a hardware identifier may uniquely identify the physical device in question. A request type may indicate the type of request. If a batch request, mode and status fields may be populated or updated as the batch request is processed. 
         [0039]    At block  510 , a database instance according to the key management schema may be created or populated. An account, role_account, and role tables may be used to identify and determine the ability of the requester to make such a request. An enumeration table may be used to list transient data such as the device or key status. A lock mode table (also called a hardware lock mode, or HLM, key table) may indicate whether the electronic device associated with the request is currently locked due to low value or tampering. Key, device and manufacturer tables may be referenced to determine the nature and status of the device and its associations with partners. 
         [0040]    At block  512 , the request may be processed. In some embodiments, a local cache may be maintained to allow faster servicing of requests. For example, an add value request may reference the current status of the electronic device, status of the user&#39;s account (e.g. in good standing), and validity of the current local time at the electronic device. When a value is not available from the local cache, a host request may be made. If the local cache has a value it may be used. In some cases, even a local value may be checked if it is ‘stale,’ that is, older than a metric for renewal. In other embodiments, a SQL notification  516  may be used to update the cache when the host recognizes a change has been made to data in the local cache. The new value may be pushed out, or, in some cases, a notification may be sent and the local cache may be updated only if the data is needed. 
         [0041]    Processing the request may include updating any of the associated portal and key management tables. From the portal and key management tables, a response may be generated, for example, an XML response. 
         [0042]    At block  514 , the response may be sent to the requesting party. Alternatively, in some cases, such as a customer service request, the response may be directed to the electronic device associated with the request, with only a confirmation being returned to the requesting device. 
         [0043]    The administration of pay-per-use electronic devices, including metered-use computers and the like, using a web-services portal requires special considerations for security and responsiveness. The use of the portal and key management schemas as described above allows those mutual goals to be achieved. XML notification for cache refreshing also adds to responsiveness and customer satisfaction. 
         [0044]    Although the forgoing text sets forth a detailed description of numerous different embodiments, it should be understood that the scope of the patent is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment because describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims. 
         [0045]    Thus, many modifications and variations may be made in the techniques and structures described and illustrated herein without departing from the spirit and scope of the present claims. Accordingly, it should be understood that the methods and apparatus described herein are illustrative only and are not limiting upon the scope of the claims.