Patent Publication Number: US-2004060002-A1

Title: Schema-based service for identity-based access to lists

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
     [0001] The present application claims priority from U.S. patent application Ser. No. 10/017,680, filed Oct. 22, 2002, which claims priority from U.S. provisional application serial No. 60/275,809, filed Mar. 14, 2001 and entitled “Identity-Based Service Communication Using XML Messaging Interfaces,” which are hereby incorporated herein by reference in their entireties. 
    
    
     
       COPYRIGHT DISCLAIMER  
       [0002] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.  
       FIELD OF THE INVENTION  
       [0003] The invention relates generally to computer network data access, and more particularly to systems, methods and data structures for accessing data and data-related services over a network.  
       BACKGROUND OF THE INVENTION  
       [0004] There are many types of data that users need to manage and otherwise access. For example, users keep word processing documents, spreadsheet documents, calendars, telephone numbers and addresses, e-mail messages, financial information, lists and so on. In general, users maintain this information on various personal computers, hand-held computers, pocket-sized computers, personal digital assistants, mobile phones and other electronic devices. In most cases, a user&#39;s data on one device is not accessible to another device, without some manual synchronization process or the like to exchange the data, which is cumbersome. Moreover, some devices do not readily allow for synchronization. For example, if a user leaves his cell phone at work, he has no way to get his stored phone numbers off the cell phone when at home, even if the user has a computing device or similar cell phone at his disposal. As is evident, these drawbacks result from the separate devices each containing their own data.  
       [0005] Corporate networks and the like can provide users with remote access to some of their data, but many users do not have access to such a network. For many of those that have access, connecting to a network with the many different types of devices, assuming such devices can even connect to a network, can be a complex or overwhelming problem.  
       [0006] Moreover, even if a user has centrally stored data, the user needs the correct type of device running the appropriate application program to access that data. For example, a user with a PDA that maintains a user&#39;s schedule (e.g., appointments, meetings and so on) with a simple to-do list application program ordinarily will not be able to use that program to open a calendar stored by an email application program or the like at work. In general, this is because the data is formatted and accessed according to the way the application program wants it to be formatted.  
       [0007] What is needed is a model wherein data is centrally stored for users, with a set of services that control access to the data with defined methods, regardless of the application program and/or device.  
       SUMMARY OF THE INVENTION  
       [0008] Briefly, the present invention provides a Lists service (.NET Lists, or myLists) for centralized (e.g., Internet) access to per-user lists, based on each user&#39;s identity, wherein the Lists service includes a schema that defines rules and a structure for the data, and also includes methods that provide access to the data in a defined way. Because the structure of the data is defined from the perspective of the data, not from that of an application program or a device, programs can communicate with the services to access the data, with existing knowledge of the format. In one implementation, the Lists schemas are arranged to provide XML documents, and the services provide methods that control access to the data based on the requesting user&#39;s identification, defined role and scope for that role. In this way, data can be accessed by its owner, and shared to an extent determined by the owner. Extensibility is defined into the schema.  
       [0009] Other benefits and advantages will become apparent from the following detailed description when taken in conjunction with the drawings, in which: 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0010]FIG. 1 is a block diagram representing an exemplary computer system into which the present invention may be incorporated;  
     [0011]FIG. 2 is a block diagram representing a generic data access model in accordance with one aspect of the present invention;  
     [0012]FIG. 3 is a representation of services for identity-based data access in accordance with one aspect of the present invention;  
     [0013]FIG. 4 is a block diagram representing a schema-based service for accessing data arranged in a logical content document based on a defined schema for that service in accordance with one aspect of the present invention. 
    
    
     DETAILED DESCRIPTION  
     [0014] Exemplary Operating Environment  
     [0015]FIG. 1 illustrates an example of a suitable computing system environment  100  on which the invention may be implemented. The computing system environment  100  is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality of the invention. Neither should the computing environment  100  be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary operating environment  100 .  
     [0016] The invention is operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of well known computing systems, environments, and/or configurations that may be suitable for use with the invention include, but are not limited to: personal computers, server computers, hand-held or laptop devices, tablet devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like.  
     [0017] The invention may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and so forth, that perform particular tasks or implement particular abstract data types. The invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in local and/or remote computer storage media including memory storage devices.  
     [0018] With reference to FIG. 1, an exemplary system for implementing the invention includes a general purpose computing device in the form of a computer  110 . Components of the computer  110  may include, but are not limited to, a processing unit  120 , a system memory  130 , and a system bus  121  that couples various system components including the system memory to the processing unit  120 . The system bus  121  may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus also known as Mezzanine bus.  
     [0019] The computer  110  typically includes a variety of computer-readable media. Computer-readable media can be any available media that can be accessed by the computer  110  and includes both volatile and nonvolatile media, and removable and non-removable media. By way of example, and not limitation, computer-readable media may comprise computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by the computer  110 . Communication media typically embodies computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of the any of the above should also be included within the scope of computer-readable media.  
     [0020] The system memory  130  includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM)  131  and random access memory (RAM)  132 . A basic input/output system  133  (BIOS), containing the basic routines that help to transfer information between elements within computer  110 , such as during start-up, is typically stored in ROM  131 . RAM  132  typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit  120 . By way of example, and not limitation, FIG. 1 illustrates operating system  134 , application programs  135 , other program modules  136  and program data  137 .  
     [0021] The computer  110  may also include other removable/non-removable, volatile/nonvolatile computer storage media. By way of example only, FIG. 1 illustrates a hard disk drive  141  that reads from or writes to non-removable, nonvolatile magnetic media, a magnetic disk drive  151  that reads from or writes to a removable, nonvolatile magnetic disk  152 , and an optical disk drive  155  that reads from or writes to a removable, nonvolatile optical disk  156  such as a CD ROM or other optical media. Other removable/non-removable, volatile/nonvolatile computer storage media that can be used in the exemplary operating environment include, but are not limited to, magnetic tape cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM, solid state ROM, and the like. The hard disk drive  141  is typically connected to the system bus  121  through a non-removable memory interface such as interface  140 , and magnetic disk drive  151  and optical disk drive  155  are typically connected to the system bus  121  by a removable memory interface, such as interface  150 .  
     [0022] The drives and their associated computer storage media, discussed above and illustrated in FIG. 1, provide storage of computer-readable instructions, data structures, program modules and other data for the computer  110 . In FIG. 1, for example, hard disk drive  141  is illustrated as storing operating system  144 , application programs  145 , other program modules  146  and program data  147 . Note that these components can either be the same as or different from operating system  134 , application programs  135 , other program modules  136 , and program data  137 . Operating system  144 , application programs  145 , other program modules  146 , and program data  147  are given different numbers herein to illustrate that, at a minimum, they are different copies. A user may enter commands and information into the computer  20  through input devices such as a tablet, or electronic digitizer,  164 , a microphone  163 , a keyboard  162  and pointing device  161 , commonly referred to as mouse, trackball or touch pad. Other input devices not shown in FIG. 1 may include a joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit  120  through a user input interface  160  that is coupled to the system bus, but may be connected by other interface and bus structures, such as a parallel port, game port or a universal serial bus (USB). A monitor  191  or other type of display device is also connected to the system bus  121  via an interface, such as a video interface  190 . The monitor  191  may also be integrated with a touch-screen panel or the like. Note that the monitor and/or touch screen panel can be physically coupled to a housing in which the computing device  110  is incorporated, such as in a tablet-type personal computer. In addition, computers such as the computing device  110  may also include other peripheral output devices such as speakers  195  and printer  196 , which may be connected through an output peripheral interface  194  or the like.  
     [0023] The computer  110  may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer  180 . The remote computer  180  may be a personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computer  110 , although only a memory storage device  181  has been illustrated in FIG. 1. The logical connections depicted in FIG. 1 include a local area network (LAN)  171  and a wide area network (WAN)  173 , but may also include other networks. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet. For example, in the present invention, the computer system  110  may comprise source machine from which data is being migrated, and the remote computer  180  may comprise the destination machine. Note however that source and destination machines need not be connected by a network or any other means, but instead, data may be migrated via any media capable of being written by the source platform and read by the destination platform or platforms.  
     [0024] When used in a LAN networking environment, the computer  110  is connected to the LAN  171  through a network interface or adapter  170 . When used in a WAN networking environment, the computer  110  typically includes a modem  172  or other means for establishing communications over the WAN  173 , such as the Internet. The modem  172 , which may be internal or external, may be connected to the system bus  121  via the user input interface  160  or other appropriate mechanism. In a networked environment, program modules depicted relative to the computer  110 , or portions thereof, may be stored in the remote memory storage device. By way of example, and not limitation, FIG. 1 illustrates remote application programs  185  as residing on memory device  181 . It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used.  
     [0025] Data Access Model  
     [0026] The present invention generally operates in an architecture/platform that connects network-based (e.g., Internet-based) applications, devices and services, and transforms them into a user&#39;s personal network which works on the user&#39;s behalf, and with permissions granted by the user. To this end, the present invention is generally directed to schema-based services that maintain user, group, corporate or other entity data in a commonly accessible virtual location, such as the Internet. The present invention is intended to scale to millions of users, and be stored reliably, and thus it is likely that a user&#39;s data will be distributed among and/or replicated to numerous storage devices, such as controlled via a server federation. As such, while the present invention will be generally described with respect to an identity-centric model that enables a user with an appropriate identity and credentials to access data by communicating with various core or other services, it is understood that the schema-based services described herein are arranged for handling the data of millions of users, sorted on a per-user-identity basis. Note that while “user” is generally employed herein for simplicity, as used herein the term “user” is really a substitute for any identity, which may be a user, a group, another entity, an event, a project, and so on.  
     [0027] As generally represented in FIG. 2, a data access model  200  includes a generic navigation module  202  through which applications  204  and the like may access a wide variety of identity-based data, such as maintained in an addressable store  206 . To access the data, a common set of command methods may be used to perform operations on various data structures that are constructed from the data in the addressable store  206 , even though each of those data structures may represent different data and be organized quite differently. Such command methods may describe generic operations that may be desired on a wide variety of data structures, and include, for example, insert, delete, replace, update, query or change-query methods.  
     [0028] In accordance with one aspect of the present invention and as described in detail below, the data is accessed according to various schemas, with the schemas corresponding to identity-based services through which users access their data. As used herein, a “schema” generally comprises a set of rules that define how a data structure may be organized, e.g., what elements are supported, in what order they appear, how many times they appear, and so on. In addition, a schema may define, via color-coding or other identification mechanisms, what portions of an XML document (that corresponds to the data structure) may be operated on. Examples of such XML-based documents are described below. The schema may also define how the structure of the XML document may be extended to include elements not expressly mentioned in the schema.  
     [0029] As will be understood below, the schemas vary depending on the type of data they are intended to organize, e.g., an email-inbox-related schema organizes data differently from a schema that organizes a user&#39;s favorite websites. Further, the services that employ schemas may vary. As such, the generic navigation module  202  has associated therewith a navigation assistance module  208  that includes or is otherwise associated with one or more schemas  210 . As will be understood, a navigation assistance module  208  as represented in FIG. 2 corresponds to one or more services, and possesses the information that defines how to navigate through the various data structures, and may also indicate which command methods may be executed on what portions of the data structure. Although in FIG. 2 only one navigation assistance module  208  is shown coupled to the generic navigation module  202 , there may be multiple navigation assistance modules that may each specialize as desired. For example, each navigation assistance module may correspond to one service. Moreover, although the navigation assistance module  208  is illustrated as a separate module, some or all of the operations of the navigation assistance module  208  may be incorporated into the generic navigation module  202 , and vice versa. In one embodiment, the various data structures constructed from the schema and addressable store data may comprise XML documents of various XML classes. In that case, the navigation assistance module  208  may contain a schema associated with each of the classes of XML documents.  
     [0030] The present invention provides a number of schema-based services that facilitate data access based on the identity of a user. Preferably, the user need not obtain a separate identity for each service, but rather obtains a single identity via a single set of credentials, such as with the Microsoft® Passport online service. With such an identity, a user can access data via these services from virtually any network connectable device capable of running an application that can call the methods of a service.  
     [0031] Services and Schemas “.NET My Services” comprises identity-centric services which may be generally implemented in XML (extensible Markup Language) Message Interfaces (XMIs). While the present invention will be described with respect to XMI and XMI, it can readily be appreciated that the present invention is not limited to any particular language or set of interfaces. The .NET My Services model essentially corresponds to one implementation of the generic data access model  200  of FIG. 2.  
     [0032] As generally represented in FIG. 3, .NET My Services  300  is implemented as a set of Web services  301 - 316 , each bound to a .NET Identity (PUID, such as a Passport® unique identifier similar to a globally unique identifier when Passport® is the authentication service). The services  301 - 316  can communicate with one another via a service-to-service communications protocol (SSCP), described below. As also described below, each service presents itself as a set of XML documents that can be manipulated from an application program  202  (FIG. 2) or the like using a set of standard methods and domain-specific methods. To this end, a user device  320  (endpoint) running such application programs connects a user&#39;s applications to the services, and the data controlled by those services, such as over the Internet or an Intranet, such as over the Internet or an Intranet. Note that endpoints can be client devices, applications or services. In keeping with the present invention, virtually any device capable of executing software and connecting to a network in any means may thus give a user access to data that the user is allowed to access, such as the user&#39;s own data, or data that a friend or colleague has specified as being accessible to that particular user.  
     [0033] In general, a .NET Identity is an identifier assigned to an individual, a group of individuals, or some form of organization or project. Using this identifier, services bound to that identity can be located and manipulated. A general effect is that each identity (e.g., of a user, group or organization) has tied to it a set of services that are partitioned along schema boundaries and across different identities. As will be understood, the XML-document-centric architecture of .NET My Services provides a model for manipulating and communicating service state that is very different from prior data access models. The L-document-centric approach, in conjunction with loose binding to the data exposed by the services, enables new classes of application programs. As will also be understood, the .NET My Services model  300  presents the various services  301 - 316  using a uniform and consistent service and method model, a uniform and consistent data access and manipulation model, and a uniform and consistent security authorization model.  
     [0034] In a preferred implementation, the .NET My Services model  300  is based upon open Internet standards. Services are accessed by means of SOAP (Simple Object Access Protocol) messages containing an XML payload. Service input and output is expressed as XML document outlines, and each of these document outlines conform to an XML schema document. The content is available to a user interacting with the .NET My Services service endpoint  320 .  
     [0035] Turning to FIG. 4, in the .NET My Services model, an application  400  requests performance of a method that operates on data structures. The application may make a request that is generic with respect to the type of data structure being operated upon and without requiring dedicated executable code for manipulating data structures of any particular data type. To this end, in one implementation the application first contacts a special myServices service  314  to obtain the information needed to communicate with a particular service  404 , through a set of methods  406  of that service  404 . For example, the needed information received from the myServices service  314  includes a URI of that service  404 . Note that the service  404  may correspond to essentially any of the services represented in FIG. 3, such as the myLists service  310 .  
     [0036] In an alternate implementation, the services and data may be available on an intranet or the like. In such an event, it may be unnecessary to use the myServices service  314 , e.g., if the URI of the desired services are fixed for any user of the intranet. Notwithstanding, a more flexible approach with an intranet may be to have the myServices service that simply provides an intranet URI, such as from a simple lookup table, whereby an administrator and the applications would not be bound to anything fixed.  
     [0037] The service  404  includes or is otherwise associated with a set of methods  406  including standard methods  408 , such as to handle requests directed to insert, delete, replace, update, query or changequery operations on the data. The set of methods of a particular service may also include service specific methods  410 . In general, the only way in which an application can communicate with a service are via that service&#39;s methods.  
     [0038] Each service includes service logic  412  for handling requests and providing suitable responses. To this end, the service logic performs various functions such as authorization, authentication, and signature validation, and further limits valid users to only the data which they are permitted to access. The security aspect of a service is not discussed herein, except to note that in general, for otherwise valid users, the user&#39;s identity determines whether a user can access data in a requested manner. To this end, a roleMap  414  comprising service-wide roleList document templates  415  and scopes (e.g., part of the overall service&#39;s schema  416 ), in conjunction with user-based data maintained in an addressable store  418 , determines whether a particular requested method is allowed, e.g., by forming an identity-based roleList document  420 . If a method is allowed, the scope information in the roleMap  414  determines a shape of data to return, e.g., how much content is allowed to be accessed for this particular user for this particular request. The content is obtained in accordance with a content document  422  in the service&#39;s schema  416  and the actual user data corresponding to that content document in the addressable store  418 . In this manner, a per-identity shaped content document  424  is essentially constructed for returning to the user, or for updating the addressable store, as appropriate for the method. Note that FIG. 4 includes a number of ID-based roleList documents and ID-based content documents, to emphasize that the service  406  is arranged to serve multiple users. Also, in FIG. 4, a system document  426  is present as part of the schema  416 , as described below.  
     [0039] Returning to FIG. 3, in one implementation, access to .NET My Services  300  is accomplished using SOAP messages formatted with .NET My Services-specific header and body content. Each of the .NET My Services will accept these messages by means of an HTTP POST operation, and generate a response by “piggy-backing” on the HTTP Response, or by issuing an HTTP POST to a .NET My Services response-processing endpoint  320 . In addition to HTTP as the message transfer protocol, .NET My Services will support raw SOAP over TCP, a transfer protocol known as Direct Internet Message Encapsulation (or DIME). Other protocols for transferring messages are feasible.  
     [0040] Because .NET My Services are accessed by protocol, no particular client-side binding code, object models, API layers, or equivalents are required, and are thus optional. The .NET My Services will support Web Services Description Language (WSDL). It is not mandatory that applications wishing to interact with .NET My Services make use of any particular bindings, and such bindings are not described herein. Instead, the present invention will be generally described in terms of messages that flow between requestors of a particular service and the service endpoints. In order to interact with .NET My Services, a service needs to format a .NET My Services message and deliver that message to a .NET My Services endpoint. In order to format a message, a client needs to manipulate XML document outlines, and typically perform some simple, known (public-domain) cryptographic operations on portions of the message.  
     [0041] In accordance with one aspect of the present invention, and as described in FIG. 4 and below, in one preferred implementation, services (including the myLists service  310 ) present three logical XML documents, a content document  422 , roleList document  415  (of the roleMap  414 ), and a system document  426 . These documents are addressable using .NET My Services message headers, and are manipulated using standard .NET My Services methods. In addition to these common methods, each service may include additional domain-specific methods, such as updateNotificationData.  
     [0042] Each .NET MyServices service thus logically includes a content document  422 , which in general is the main, service-specific document. The schema for this document  422  is a function of the class of service, as will become apparent from the description of the myLists service&#39;s content document below. For example, in the case of the myLists service  310 , the content document presents data in the shape dictated by the .NET My Services MyLists schema, whereas in the case of the “.NET FavoriteWebSites” service  308 , the content document presents data in the shape dictated by a .NET myFavoriteWebSites schema.  
     [0043] Each service also includes a roleList document  415  that contains roleList information, comprising information that governs access to the data and methods exported by the service  404 . The roleList document is manipulated using the .NET My Services standard data manipulation mechanisms. The shape of this document is governed by the .NET My Services core schema&#39;s roleListType XML data type.  
     [0044] Each service also includes a system document  426 , which contains service-specific system data such as the roleMap, schemaMap, messageMap, version information, and service specific global data. The document is manipulated using the standard .NET data manipulation mechanism, although modifications are limited in a way that allows only the service itself to modify the document. The shape of this system document  426  may be governed by the system document schema for the particular service, in that each service may extend a base system document type with service specific information.  
     [0045] As is understood, the present invention is generally based on schemas, which in general comprise a set of rules or standards that define how a particular type of data can be structured. Via the schemas, the meaning of data, rather than just the data itself, may be communicated between computer systems. For example, a computer device may recognize that a data structure that follows a particular address schema represents an address, enabling the computer to “understand” the component part of an address. The computer device may then perform intelligent actions based on the understanding that the data structure represents an address. Such actions may include, for example, the presentation of an action menu to the user that represents things to do with addresses. Schemas may be stored locally on a device and/or globally in a federation&#39;s “mega-store.” A device can keep a locally-stored schema updated by subscribing to an event notification service (in this case, a schema update service) that automatically passes messages to the device when the schema is updated. Access to globally stored schemas is controlled by the security infrastructure.  
     [0046] General Schema Commonality  
     [0047] The .NET My Services data is defined using annotated XSD schema files. The XSD files accurately type the data, but since XSD is a verbose and complex language, it is not a particularly efficient way to convey structure and meaning. Thus, for purposes of simplicity herein, the myLists schemas are described below in terms of schema outlines with accompanying element/attribute descriptions. These document outlines accurately show the structure of the data contained within a service. However, because the present application is not viewable in color, the nodes, elements and/or attributes of the schema outlines (which may be described as bold blue, or blue), are represented in the schema outlines as boldface type. Those described as underlined red, or red, are represented as underlined type, while others referred to as black are represented in normal type.  
     [0048] The meaning of these bold (blue), underlined (red) and normal (black) items has significance with respect to the data model and to the data language that accesses and manipulates the data (e.g., via the insert, delete, replace, update, query, changequery or other methods). For example, each document described below contains a root element having an element name that matches that of the service, e.g., the myLists service has a root element named myLists. The .NET My Services name for this item is the root.  
     [0049] Documents contain elements that resemble first-class top-level objects, including, for example, &lt;catDef/&gt;, &lt;myApplicationsSettings /&gt; (other another name as appropriate) and &lt;order/&gt;. Such items are denoted in the outlines as bold (blue), and may be identified using an &lt;xdb:blue/&gt;tag. Bold (blue) items define major blocks of data within a service. These node sets are directly addressable by an identifier attribute, and their change status is tracked through a changeNumber attribute. Top-level bold blue items may be considered objects. As seen below, some bold (blue) objects contain nested bold blue objects. They usually contain frequently changing underlined (red) properties, which reduces the amount of synchronization traffic. Nested bold (blue) items may be considered property groups.  
     [0050] Each bold blue item contains one or more underlined (red) items which are elements or attributes. These items may be identified using the &lt;xdb:red/&gt;tag. These items are special in that they may be used within predicates (filters) to aid in xdb:bold blue selection. These items are also directly addressable and may be manipulated directly by the data manipulation language.  
     [0051] Each underlined (colored red) element may contain one or more non-colorized elements and attributes, which are valid and semantically meaningful XML items in the service document. Such items are opaque to the data language. These uncolored (i.e., non-bold or underlined) elements and attributes may not be addressed directly, may not be selected in a node selection operation, and may not be used in a predicate node test. Note that if one of these items is in the path to an underlined red item, it may be used in a location step to the underlined red item, but may not be used as the selected node. Note that being opaque does not mean that the item is not considered during schema validation, but rather means that the item may not be used in a predicate, may not be directly addressed, and may not be inserted by itself As can be readily appreciated, in this manner, the .NET My Services thus limits the granularity of access to nodes within the service document, since only xdb:bold blue and xdb:underlined red marked items are directly addressable, and only those elements and attributes tagged with the xdb:underlined red annotation may be used in predicates to influence node selection. Using this technique, the .NET My Services storage system can efficiently manage indexes, increase the performance of node selection, partially shred the document data, and in general (because the node selections are well defined) fine-tune the node selection logic on a per-xdb:blue basis. The primary purpose of the xdb:blue is to define a base-level XML object that is designed to be operated on as a unit. The primary purpose of the xdb:red items is to aid in the selection of xdb:bold blues. The xdb:red items may be changed by the data language primitives so some level of fine-grained manipulation of the data is available, but only in very limited ways.  
     [0052] Bold blue items have unique IDs, which are usually assigned by .NET My Services, and are returned from update operations within the new blueId node. In all cases, the order of xxxBold blue follows the pre-order traversal of the document XML tree. Item IDs are UUIDs in the following format (h stands for a hexadecimal digit): hhhhhhhh-hhhh-hhhh-hhhh-hhhhhhhhhhhh.  
     [0053] In addition to identifiers, names and change numbers, nodes and especially red nodes may include creator identifiers, category information, and {any} fields. Category information enables data to be grouped and/or distinguished in some way, such as to share certain calendar information with golf buddies, send an email to immediately family, designate things such as which telephone number is the user&#39;s primary number, e.g., if a user has a second home, and so on. Fields of type “any” may comprise fully-typed, namespace-qualified fields that contain any type of content (e.g., free-form XML) therein. Such “any” fields thus allow extensibility of the schema, yet maintain the defined structure of a schema.  
     [0054] In one implementation, the core data-manipulation language implemented by the .NET My Services includes an insertRequest, or insert message. This primitive inserts any schema-valid XML fragment into a selected context, thereby changing the existing state of the document. A queryRequest, or message, retrieves data, such as to retrieve a document. Multiple queries may be specified in one request, and queries that select nothing are considered successful. It is possible to assert that the number of nodes in the selection falls in a given range. This is expressed using minOccurs and maxOccurs attributes. If a minOccurs/maxOccurs test fails on any node, the request is considered unsuccessful. Note that this is different from a failure code, which would be returned, for example, for a malformed request.  
     [0055] A deleteRequest primitive deletes the selected nodes and all their children. Note that, just like for other requests, attributes may be selected as well as elements. Empty selections result in successful operations, similar to Query. The minOccurs/maxOccurs tests are supported wherever select is allowed.  
     [0056] A replaceRequest primitive (replace message) is designed to replace the content of each of the selected nodes with the specified new content. Selected nodes themselves are not affected in any way. This may be considered as an atomic delete of the content of the selected node, followed by an insert. The content (text, attributes, elements) in the selected nodes are replaced with the new item specified in this message. The node type of the selected node and of the replacement node are thus required to be the same. The changequery request essentially returns result comprising data that has changed.  
     [0057] As mentioned above, each of the services includes a RoleList document and scope information that describes which users have what type of access to which data. For example, a data owner will have read/write access to his or her own data, and can provide various types of rights to that data to other users based on their IDs, (e.g., read only to some users, read write to others). Each role list identifier may be associated with a scope, by which the kinds of data stored according to a given schema can be controlled per user. For example, a user can give a friend (with one identity) access via a service to a home telephone number, home address and so forth, but can give other users (with other identities) access only to a business telephone number. In general, a scope can be defined such that that it includes everything except any specifically listed items, or excludes everything except any specifically listed items.  
     [0058] .NET Lists (myLists) Service  
     [0059] The .NET Lists service is a general purpose service designed to manage simple lists with minimal structure for what a list is, and what an item is within a list. Like other .NET My Services, the .NET Lists service allows free-form, name-space qualified extensions to be added to a list, or an item within a list. This mechanism is useful to add semi-structured information to the service, although with such freeform extensions, the service is unable to schema-validate these extensions.  
     [0060] The .NET Lists service breaks down a list into two major components which are the list defined by the list element, and an item defined by the item element.  
     [0061] The list element is designed to contain the definition of a list, and serves as an anchor location to which items that belong to that list may refer. Lists may also refer to lists. In any event, the linkage is designed to be a soft linkage so that list definitions may be defined within the confines of the .NET Lists service as well as external to the service. This linkage pattern is that same as the linkage pattern used between element categorization and category definitions, (e.g., as defined in the .NET Category section in the aforementioned U.S. patent application Ser. No. 10/017,680). With this linkage model, the service is able to support personal list definitions in the per-user content document, global list definitions in the shared system document, and external list definitions stored in other addressable resources. The .NET Lists service defines a number of pre-defined lists in the system document. An xpQuery of //sys:list from the .NET Lists service&#39;s system document will return these lists.  
     [0062] The item element is designed to represent something that belongs to one or more lists. An item may be categorized (personal, private, sports, and so on) using standard .NET My Services categorization techniques, must have a title, an optional full description, may contain external references via the URL namespace, may be associated or “assigned” to another user, and so on. As noted above, an item refers to a list element, and may in fact refer to multiple list elements. There are however no referential integrity checks made through these references because as will be seen, some will likely use the reference itself as an implicit definition of a list element and in some cases, that element may not exist or may be inaccessible.  
     [0063] An item associates itself with one or more lists by using the listRef element and specifying a relative or absolute URI in the listRef/@ref attribute. The URI is able to refer to a list element by name where the list element is physically stored in the system document of the .NET Lists service, the content document of the .NET Lists service and/or an arbitrary XML file located by URI containing list elements.  
     [0064] The listRef element refers to a list definition by absolute or relative URI. The linkage between the two is through the list/@idName attribute and the listRef/@ref attribute. The list/@idName attribute specifies the local id for the list definition, and the listRef/@ref attribute is the value of that reference.  
     [0065] The value of the listRef/@ref attribute may take the form:  
     [0066] system#name-of-list  
     [0067] The list definition being referenced is located in the system document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. For example, the list reference of &lt;listRef ref=“system#todo”/&gt; is a reference to the list definition whose list/@idName value is “todo”, and that this list definition is located in the system document of the .NET Lists service i.e. &lt;list idName=“todo”/&gt;.  
     [0068] The value of the listRef/@ref attribute may also take the form:  
     [0069] content[?puid=puid-value]#name-of-list  
     [0070] The list definition being referenced is located in the content document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. The instance of the .NET Lists service (i.e., the puid of the service) is implied by the context of the reference. This may be made explicit by inserting ?puid=puid-value to the URI, and when this is done, it means the content document of the .NET Lists service whose puid is “puid-value” holds the list definition. For example, the list reference of &lt;listRef ref=“content#bellSqaureShopping”/&gt; is a reference to the list definition whose list/@idName value is “bellSquareShopping”, and that this list definition is located in the content document of the .NET Lists service for the current puid i.e. &lt;list idName=“bellSquareShopping”/&gt;.  
     [0071] The value of the listRef/@ref attribute may also take the form:  
     [0072] any-uri#name-of-list  
     [0073] The category list being referenced is located in an external (to .NET My Services) resource. The “any-uri” portion of the reference refers to a resource containing the list element whose @idName attribute matches the “name-of-list”. The mapping between the “any-uri” portion of the reference and an XML document containing the list elements is a function of the “any-uri”. By convention, this uri is the name of an XML document containing those elements. The purpose of this reference form is to allow and support a free form set of extended list definitions that are global and available to all. For example, the list reference of &lt;cat ref=“http://schemas.xyz.com/im/lists.xml#imChatRoom”/&gt; is a reference to the list definition whose list/@idName value is “imChatRoom”, and that this category definition is located in an external resource located at “http://schemas.xyz.com/im/lists.xml”. Note that it is expected that list definitions will exist in the appropriate locations, but there is no requirement or enforcement of this.  
     [0074] In any events, the mapping between a listRef reference, and the list definition is very simple:  
     [0075] 1. Locate the document containing the list definition by taking the name prior to the “#”.  
     [0076] 2. If the document is “system”, then the document containing the list definition is the system document of the .NET Lists service and is addressed using request/@(service=“myLists” and request/@document=“system”.  
     [0077] 3. If the document is “content”, then the document containing the list definition is the content document of the .NET Lists service and is addressed using request/@service=“myLists” and request/@document=“content”. If the ?puid=puid-value argument is present, the request is further qualified by request/key/@puid=“puid-value”. Otherwise, this attribute contains the puid of the document containing the reference.  
     [0078] 4. For any other document, the value is the uri of the XML document containing the list definition.  
     [0079] 5. Locate the list idName which is the portion of the reference after the “#”.  
     [0080] 6. With the document in hand, the xpath expression //list[@idName=‘list-id’] selects the list definition.  
     [0081] Like several other .NET My Services, the .NET Lists service makes use of categorization in order to classify, and categorize, both lists and elements.  
     [0082] myLists/Roles  
     [0083] The myLists service controls access by using the rt0, rt1, rt2, rt3 and rt99 roleTemplates, using the following scopes:  
                                                  scope allElements           &lt;hs:scope id=7215df55-e4af-449f-a8e4-72a1f7c6a987&gt;                         &lt;hs:shape base=t&gt;           &lt;/hs:shape&gt;                         &lt;/hs:scope&gt;           scope onlySelfElements           &lt;hs:scope id=a159c93d-4010-4460-bc34-5094c49c1633&gt;                         &lt;hs:shape base=nil&gt;                         &lt;hs:include select=//*[@creator=‘$callerId’]/&gt;                         &lt;/hs:shape&gt;                         &lt;/hs:scope&gt;           scope onlySelfSubscriptionElements           &lt;hs:scope id=b7f05a6d-75cd-4958-9dfb-f532ebb17743&gt;                         &lt;hs:shape base=nil&gt;                         &lt;hs:include select=//subscription[@creator=‘$callerId’]/&gt;                         &lt;/hs:shape&gt;                         &lt;/hs:scope&gt;           scope onlyPublicElements           &lt;hs:scope id=da025540-a0c0-470f-adcf-9f07e5a5ec8f&gt;                         &lt;hs:shape base=nil&gt;                         &lt;hs:include select=//*[cat/@ref=‘hs:public’]/&gt;           &lt;hs:include select=//subscription[@creator=‘$callerId’]/&gt;                         &lt;/hs:shape&gt;                         &lt;/hs:scope&gt;                      
 
     [0084] The myLists roleTemplate rt0 role gives complete read/write access to the information within the content document of the service being protected through this roleTemplate. The following table illustrates the available methods and the scope in effect when accessing the myLists service through that method while mapped to this roleTemplate:  
               TABLE                          myLists roleTemplate rt0                             method   scope/name                       Query   allElements           Insert   allElements           Replace   allElements           Delete   allElements           Update   allElements                      
 
     [0085] The myLists roleTemplate rt1 role gives complete read access to all information within the content document of the service being protected through this roleTemplate. Applications mapping to this role also have a limited ability to write to information in the content document. Applications may create nodes in any location, but may only change/replace, or delete nodes that they created. The following table illustrates the available methods and the scope in effect when accessing the myLists service through that method while mapped to this roleTemplate:  
               TABLE                          myLists roleTemplate rt1                             method   scope/name                       Query   allElements           Insert   onlySelfElements           Replace   onlySelfElements           Delete   onlySelfElements                      
 
     [0086] The myLists roleTemplate rt2 role gives complete read access to the information within the content document of the service being protected through this roleTemplate. Applications mapping to this role have very limited write access and are only able to create and manipulate their own subscription nodes. The following table illustrates the available methods and the scope in effect when accessing the myLists service through that method while mapped to this roleTemplate:  
               TABLE                          myLists roleTemplate rt2                             method   scope/name                       Query   allElements           Insert   onlySelfSubscriptionElements           replace   onlySelfSubscriptionElements           Delete   onlySelfSubscriptionElements                      
 
     [0087] The myLists roleTemplate rt3 role gives limited read access to information within the content document that is categorized as “public.” The following table illustrates the available methods and the scope in effect when accessing the myLists service through that method while mapped to this roleTemplate:  
                              myLists roleTemplate rt3                             method   scope/name                       Query   onlyPublicElements                      
 
     [0088] The myLists roleTemplate rt99 blocks access to the content document. Note that lack of a role in the roleList has the same effect as assigning someone to rt99.  
     [0089] myLists/Content  
     [0090] The content document is an identity centric document, with its content and meaning a function of the user identifier (puid) used to address the service. Accessing the document is controlled by the associated roleList document. The following table comprises a schema outline that illustrates the layout and meaning of the information found in the content document for the myLists service:  
                                    &lt;m:myLists    changeNumber     =″...″ instanceId=″...″                         xmlns:m=″http://schemas.microsoft.com/hs/2001/10/myLists″           xmlns:hs=″http://schemas.microsoft.com/hs/2001/10/core″&gt; 1..1             &lt; m:list    idName     =″...″    changeNumber   =″...″  id =″...″    creator   =″...″&gt; 0 unbounded                           &lt;   m:cat       ref   =″...″&gt; 0 unbounded &lt;/   m:cat   &gt;           &lt;   m:listRef       ref   =″...″ order=″...″&gt; 0 unbounded &lt;/   m:listRef   &gt;           &lt;   m:title    xml:lang=″...″ dir=″...″&gt; 0 unbounded &lt;/   m:title   &gt;           &lt;m:description xml:lang=″...″ dir=″...″&gt; 0 unbounded &lt;/m:description&gt;           &lt;m:status&gt; 0..1 &lt;/m:status&gt;               {any}                             &lt;/ m:list &gt;           &lt; m:item    changeNumber     =″...″    id   =″...″    creator   =″...″&gt; 0 unbounded                           &lt;   m:cat       ref   =″...″&gt; 0 unbounded &lt;/   m:cat   &gt;           &lt;   m:title    xml:lang=″...″ dir=″...″&gt; 0 unbounded &lt;/   m:title   &gt;           &lt;m:description xml:lang=″...″ dir=″...″&gt; 0 unbounded &lt;/m:description&gt;           &lt;m:url&gt; 0 unbounded &lt;/m:url&gt;           &lt;   m:listRef       ref   =″...″ order=″...″&gt; 1 unbounded &lt;/   m:listRef   &gt;           &lt;   m:date       ref   =″...″&gt; 0 unbounded &lt;/   m:date   &gt;           &lt;   m:status   &gt; 0 1 &lt;/   m:status   &gt;           &lt;   m:priority   &gt; 0 1 &lt;/   m:priority   &gt;           &lt;m:assignedTo&gt; 0 unbounded                           &lt;hs:name xml:lang=″...″ dir=″...″&gt; 0 .1 &lt;/hs:name&gt;           &lt;hs:puid&gt; 0 1 &lt;/hs:puid&gt;           &lt;hs:email&gt; 0 1 &lt;/hs:email&gt;                         &lt;/m:assignedTo&gt;               {any}                             &lt;/ m:item &gt;           &lt; m:subscription    changeNumber     =″...″    id   =″...″    creator   =″...″&gt; 0 unbounded                           &lt;hs:trigger select=″...″ mode=″...″ baseChangeNumber=″...″&gt; 1 1 &lt;/hs:trigger&gt;           &lt;hs:expiresAt&gt; 0 1 &lt;/hs:expiresAt&gt;           &lt;hs:context uri=″...″&gt; 1 1    {any} &lt;/hs:context&gt;           &lt;hs:to&gt; 1 1 &lt;/hs:to&gt;                         &lt;/ m:subscription &gt;             {any}                   &lt;/ m:myLists &gt;                  
 
     [0091] The meaning of the attributes and elements shown in the table are set forth below, wherein in the syntax used in the table, boldface type corresponds to a blue node, and underlined type to a red node, as described above, and the minimum occurrence information (0, 1) indicates whether an element or attribute is required or optional, and maximum occurrence information (1, unbounded) indicates whether one or many are possible.  
     [0092] The /myLists (minOccurs=1 maxOccurs=1) element encapsulates the content document for the .NET Lists service. The /myLists/@changeNumber (minOccurs=maxOccurs=1) changeNumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0093] The /myLists/@instanceId (string minOccurs=0 maxOccurs=1) attribute is a unique identifier typically assigned to the root element of a service. It is a read-only element and assigned by the .NET My Services system when a user is provisioned for a particular service.  
     [0094] The /myLists/list (minOccurs=0 maxOccurs=unbounded) element defines a list which includes categorization of the list, a localized name for the list, a brief description of the list, and any other application specific properties contained within the any block(s).  
     [0095] The /myListsAist/@idName (string minOccurs=0 maxOccurs=1) attribute specifies the name of the list that can be used in a list reference. Note that list references are coded as URIs in both absolute, and myLists relative forms. This attribute is the value of the fragment identifier from those URIs. For example, a listRef/@ref value of “system#todo” would map to a list element whose @idName attribute was todo, and that is located in the system document of the myLists service.  
     [0096] The /myLists/list/@changeNumber (minOccurs=0 maxOccurs=1) changenumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0097] The /myLists/list/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored.  
     [0098] The /myLists/list/@creator (string minOccurs=0 maxOccurs=1) attribute identifies the creator in terms of userId, appId, and platformId of the node.  
     [0099] The /myLists/list/cat (minOccurs=0 maxOccurs=unbounded) element is used to categorize the element that contains it by referencing a global category definition in either the .NET Categories service system document or an external resource containing category definitions, or by referencing an identity centric category definition in the content document of the .NET Categories service for a particular puid. The /myLists/list/cat/@ref (anyURI minOccurs=0 maxOccurs=1) attribute references a category definition (&lt;catDef/&gt;) element using the rules outlined in the myCategories section described above.  
     [0100] The /myLists/list/listRef (minOccurs=0 maxOccurs=unbounded) element specifies the lists that this item is considered contained within. Note that it is valid to have a free-form list item that is not considered to be in part of any list, which is why this element is not required (minOccurs=0).  
     [0101] The /myLists/list/listRef/@ref (anyURI minOccurs=0 maxOccurs=1) attribute contains the name of a list element encoded as a URI. The URI follows encoding rules similar to those used in cat/catDef linkage:  
     [0102] system#name-of-list  
     [0103] The list (definition) being referenced is located in the system document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. For example, the listRef of &lt;listRef ref=“system#todo”/&gt; is a reference to the list definition whose list/@idName value is “todo”, and that this list definition is located in the system document of the .NET Lists service i.e. &lt;list name=“todo”/&gt;.  
     [0104] content[?puid=puid-value]#name-of-list  
     [0105] The list definition being referenced is located in the content document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. The instance of the .NET Lists service (i.e., the puid of the service) is implied by the context of the reference. This may be made explicit by inserting ?puid=puid-value to the URI, and when this is done, it means the content document of the .NET Lists service whose puid is “puid-value” holds the list definition. For example, the list reference of &lt;listRef ref=“content#bellSqareShopping”/&gt; is a reference to the list definition whose list/@idName value is “bellSquareShopping”, and that this list definition is located in the content document of the .NET List service for the current puid i.e. &lt;list name=“bellSquareShopping”/&gt;.  
     [0106] any-uri#name-of-list  
     [0107] The list definition being referenced is located in an external (to .NET My Services) resource. The “any-uri” portion of the reference refers to a resource containing the list element whose @idName attribute matches the “name-of-list”. The mapping between the “any-uri” portion of the reference and an XML document containing the list elements is a function of the “any-uri”. By convention, this uri is the name of an XML document containing those elements. The purpose of this reference form is to allow and support a free form set of extended list definitions that are global and available to all. For example, the list reference of &lt;listRef ref=“http://schemas.xyz.com/im/globalLists.xml#xyzStuff”/&gt; is a reference to the list definition whose list/@idName value is “xyzStuff”, and that this list definition is located in an external resource located at “http://schemas.xyz.com/im/globaILists.xml”. Note that it is expected that list definitions will exist in the appropriate locations, but there is no requirement or enforcement of this.  
     [0108] The /myLists/list/listRef/@order (int minOccurs=0 maxOccurs=1) attribute contains an optional numeric order for the containing item relative to this list. Since an item (or even a list) may logically be contained within multiple lists, the order of the item is attached to the list reference so that an item&#39;s order can vary based on the list that it is contained within.  
     [0109] The /myLists/list/title (string minOccurs=0 maxOccurs=unbounded) element specifies the title of the list. The /myLists/list/title/@xrnl:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /myLists/list/title/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the default layout direction for the localized string. Valid values are rtl (right to left), and ltr (left to right).  
     [0110] The /myLists/list/description (string minOccurs=0 maxOccurs=unbounded) element specifies a more detailed description of the list. The /myLists/list/description/@xml:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /myLists/list/description/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the base direction of directionally neutral text. Possible values include rtl (right to left), or ltr (left to right).  
     [0111] The /myLists/list/status (anyURI minOccurs=0 maxOccurs=1) contains a status value for a list the optional status of that list. This elements value is coded as a category reference and follows the same rules as found in the usage of cat/@ref. The value may reference a category in the myCategories system document, a private status value in the user&#39;s myCategories content document, or an external category definition. It is expected that pre-defined system category values in the “system#status” category will be used and this would mean that expected values for this element include system#notStarted, system#inProgress, system#completed, system#waiting and system#defered.  
     [0112] A node select of “//sys:catDef[hs:cat[@ref=‘system#status’]” will locate all definitions for system defined status values.  
     [0113] The /myLists/list/{any} (minOccurs=0 maxOccurs=unbounded) provides extensibility.  
     [0114] The /myLists/item (minOccurs=0 maxOccurs=unbounded) element defines a list item, something that is considered as part of a list. An item may be part of multiple lists by including multiple listRef elements. These listRef elements may refer to list elements in the content document, the system document, or to external resources containing list elements.  
     [0115] The /myLists/item/@changeNumber (minOccurs=0 maxOccurs 1) changenumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0116] The /myLists/item/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored.  
     [0117] The /myLists/item/@creator (string minOccurs=0 maxOccurs=1) attribute identifies the creator in terms of userId, appId, and platformId of the node.  
     [0118] The /myLists/item/cat (minOccurs=0 maxOccurs=unbounded) element is used to categorize the element that contains it by referencing a global category definition in either the .NET Categories service system document or an external resource containing category definitions, or by referencing an identity centric category definition in the content document of the .NET Categories service for a particular puid.  
     [0119] The /myLists/item/cat/@ref (anyURI minOccurs=0 maxOccurs=1) attribute references a category definition (&lt;catDef/&gt;) element using the rules outlined in the myCategories section described above.  
     [0120] The /myLists/item/title (string minOccurs=0 maxOccurs=unbounded) element specifies the title of the list item. The /myLists/item/title/@xml:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /myLists/item/title/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the default layout direction for the localized string. Valid values are rtl (right to left), and ltr (left to right).  
     [0121] The /myLists/item/description (string minOccurs=0 maxOccurs=unbounded) element specifies a more detailed description of the list item. The /myLists/item/description/@xml:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /myLists/item/description/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the base direction of directionally neutral text. Possible values include rtl (right to left), or ltr (left to right).  
     [0122] The /myLists/item/url (anyURI minOccurs=0 maxOccurs=unbounded) optional element specifies a URL associated with this list item.  
     [0123] The /myLists/item/listRef (minOccurs=1 maxOccurs=unbounded) element specifies the lists that this item is considered contained within.  
     [0124] The /myLists/item/listRef/@ref (anyURI minOccurs=0 maxOccurs=) attribute contains the name of a list element encoded as a URI. The URI follows encoding rules similar to those used in cat/catDef linkage:  
     [0125] system#name-of-list  
     [0126] The list (definition) being referenced is located in the system document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. For example, the listRef of &lt;listRef ref=“system#todo”/&gt; is a reference to the list definition whose list/@idName value is “todo”, and that this list definition is located in the system document of the .NET Lists service i.e.&lt;list name=“todo”/&gt;.  
     [0127] content[?puid=puid-value]#name-of-list  
     [0128] The list definition being referenced is located in the content document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. The instance of the .NET Lists service (i.e., the puid of the service) is implied by the context of the reference. This may be made explicit by inserting ?puid=puid-value to the URI, and when this is done, it means the content document of the .NET Lists service whose puid is “puid-value” holds the list definition. For example, the list reference of &lt;listRef ref=“content#bellSqareShopping”/&gt; is a reference to the list definition whose list/@idName value is “bellSquareShopping”, and that this list definition is located in the content document of the .NET List service for the current puid i.e.&lt;list name=“bellSquareShopping”/&gt;.  
     [0129] any-uri#name-of-list  
     [0130] The list definition being referenced is located in an external (to .NET My Services) resource. The “any-uri” portion of the reference refers to a resource containing the list element whose @idName attribute matches the “name-of-list”. The mapping between the “any-uri” portion of the reference and an XML document containing the list elements is a function of the “any-uri”. By convention, this uri is the name of an XML document containing those elements. The purpose of this reference form is to allow and support a free form set of extended list definitions that are global and available to all. For example, the list reference of &lt;listRef ref=“http://schemas.xyz.com/im/globalLists.xml#xyzStuff”/&gt; is a reference to the list definition whose list/@idName value is “xyzStuff”, and that this list definition is located in an external resource located at “http://schemas.xyz.com/im/globalLists.xml”. Note that it is expected that list definitions will exist in the appropriate locations, but there is no requirement or enforcement of this.  
     [0131] The /myLists/item/listRef/@order (int minOccurs=0 maxOccurs=1) attribute contains an optional numeric order for the containing item relative to this list. Since an item (or even a list) may logically be contained within multiple lists, the order of the item is attached to the list reference so that an item&#39;s order can vary based on the list that it is contained within.  
     [0132] The /myLists/item/date (dateTime minOccurs=0 maxOccurs=unbounded) optional element specifies a categorized date/time for this item. A single optional category reference may be attached to the date. It is expected that system defined dates like “system#dueDate” will be used, but this is not meant to be limiting.  
     [0133] The /myLists/item/date/@ref (anyURI minOccurs=0 maxOccurs=1) optional attribute is a reference to an existing category for this date. For instance, a value of “system#dueDate” implies that this date is a due date.  
     [0134] The /myLists/item/status (anyURI minOccurs=0 maxOccurs=1) status value for an item indicates the optional status of that item. This element&#39;s value is coded as a category reference and follows the same rules as found in the usage of cat/@ref. The value may reference a category in the myCategories system document, a private status value in the user&#39;s myCategories content document, or an external category definition. It is expected that pre-defined system category values in the “system#status” category will be used and this would mean that expected values for this element include system#notStarted, system#inProgress, system#completed, system#waiting and system#defered.  
     [0135] A node select of “//sys:catDef[hs:cat[@ref=‘system#status’]” will locate all definitions for system defined status values.  
     [0136] The /myLists/item/priority (anyURI minOccurs=0 maxOccurs=1) contains a priority value for an item indicates the optional importance, or priority of that item. This elements value is coded as a category reference and follows the same rules as found in the usage of cat/@ref. The value may reference a category in the myCategories system document, a private priority value in the user&#39;s myCategories content document, or an external category definition. It is expected that pre-defined system category values in the “system#priority” category will be used and this would mean that expected values for this element include system#lowest, system#belowNormal, system#normal, system#aboveNormal and system#highest.  
     [0137] A node select of “//H/sys:catDef[hs:cat[@ref=‘system#priority’]” will locate all definitions for system defined priority values.  
     [0138] The /myLists/item/assignedTo (minOccurs=0 maxOccurs=unbounded) optional element may be repeated and specifies who the item is “assigned” to. It is most useful when sharing a list in myLists.  
     [0139] The /myLists/item/assignedTo/name (string minOccurs=0 maxOccurs=1) optional element specifies the name for the enclosing element. The /myLists/item/assignedTo/name/@xml:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /myLists/item/assignedTo/name/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the default layout direction for the localized string. Valid values are rtl (right to left), and ltr (left to right).  
     [0140] The /myLists/item/assignedTo/puid (string minOccurs=0 maxOccurs=1) optional element specifies the name for the enclosing element. The /myLists/item/assignedTo/email (string minOccurs=0 maxOccurs=1) optional name specifies an email address for the enclosing element. The /myLists/item/{any} (minOccurs=0 maxOccurs=unbounded) and /myLists/list/{any} (minOccurs=0 maxOccurs=unbounded) allows for extensibility of this schema.  
     [0141] The /myLists/subscription (minOccurs=0 maxOccurs=unbounded) element defines a subscription node as described above in the subscription section.  
     [0142] The following table illustrates the structure and contents of a simple “tripList” list. Note that changeNumbers, creator attributes, and other bookkeeping items are not included in this example for purposes of simplicity.  
                                  &lt; myLists &gt;                         &lt; list    idName     =“tripList”    id   =“1”&gt;                         &lt;title xml:lang=“en” dir=“ltr”&gt;SVC Trip, Todo List&lt;/title&gt;           &lt;listRef    idName   =“system#todo” order=“1”/&gt;           &lt;status&gt;system#inProgress&lt;/status&gt;                         &lt;/ list&gt;             &lt; item    id     =“2”&gt;                         &lt;   title    xml:lang=“EN”&gt;Make Dental Appointment&lt;/   title   &gt;           &lt;listRef    idName   =“content#tripList” order=“1”/&gt;           &lt;   status   &gt;system#notStarted&lt;/   status   &gt;                         &lt;/   item   &gt;           &lt; item    id     =“3”&gt;                         &lt;   title    xml:lang=“EN”&gt;Pick up Suit&lt;/   title   &gt;           &lt;listRef    idName   =“content#tripList” order=“2“/&gt;           &lt;   status   &gt;system#notStarted&lt;/   status   &gt;                         &lt;/ item&gt;             &lt; item    id     =“3”&gt;                         &lt;   title    xml:lang=“EN”&gt;Work on Resume&lt;/   title   &gt;           &lt;listRef    idName   =“content#tripList” order=“1”/&gt;           &lt;   status   &gt;system#inProgress&lt;/   status   &gt;                         &lt;/ item &gt;                 &lt;/ myLists &gt;                  
 
     [0143] With this information, a simple list display might present this list as:  
                               SVC Trip, Todo List                                                Not Started   Make Dental Appointment           Not Started   Pick up Suit           In Progress   Work on Resume                      
 
     [0144] The following table illustrates the structure and contents of a simple “trip” list and a shopping list for things to purchase or pick up at the mall. Note that some elements appear in both lists. Further, note that changeNumbers, creator attributes and other bookkeeping items are not included in this example for simplicity.  
                                  &lt; myLists &gt;                         &lt; list    idName     =“tripList”    id   =“1”&gt;                         &lt;title xml:lang=“en” dir=“ltr”&gt;SVC Trip, Todo List&lt;/title&gt;           &lt;listRef    idName   =“system#todo” order=“1”/&gt;           &lt;status&gt;system#inProgress&lt;/status&gt;                         &lt;/ list &gt;           &lt; item    id     =“2”&gt;                         &lt;   title    xml:lang=“EN”&gt;Make Dental Appointment&lt;/   title   &gt;           &lt;listRef    idName   =“content#tripList” order=“1”/&gt;           &lt;   status   &gt;system#notStarted&lt;/   status   &gt;                         &lt;/ item &gt;           &lt; item    id     =“3”&gt;                         &lt;   title    xml:lang=“EN”&gt;Pick up Suit&lt;/   title   &gt;           &lt;listRef    idName   =“content#tripList” order=“2”/&gt;           &lt;listRef    idName   =“system#shopping” order=“1”/&gt;           &lt;   status   &gt;system#notStarted&lt;/   status   &gt;                         &lt;/ item &gt;           &lt; item    id     =“3”&gt;                         &lt;   title    xml:lang=“EN”&gt;Work on Resume&lt;/   title   &gt;           &lt;listRef    idName   =“content#tripList” order=“1”/&gt;           &lt;   status   &gt;system#inProgress&lt;/   status   &gt;                         &lt;/ item &gt;           &lt; item    id     =“4”&gt;                         &lt;   title    xml:lang=“EN”&gt;Tennis Shoes&lt;/   title   &gt;           &lt;listRef    idName   =“system#shopping” order=“3”/&gt;           &lt;   status   &gt;notStarted&lt;/   status   &gt;                         &lt;/ item &gt;           &lt; item    id     =“5”&gt;                         &lt;   title    xml:lang=“EN”&gt;Buy a CD&lt;/   title   &gt;           &lt;listRef    idName   =“system#shopping” order=“2”/&gt;           &lt;   status   &gt;notStarted&lt;/   status   &gt;                         &lt;/ item &gt;                 &lt;/ myLists &gt;                  
 
     [0145] With this information, a simple list display might present these lists as:  
                               SVC Trip, Todo List                                                Not Started   Make Dental Appointment           Not Started   Pick up Suit           In Progress   Work on Resume                      
 
     [0146]                               Shopping                                                Not Started   Pick up Suit           Done   Buy a CD           Not Started   Tennis               Shoes                        
     [0147] myLists/System  
     [0148] The system document is a global document for the service, having content and meaning that are independent of the puid used to address the service. The document is read only to all users. The system document contains a set of base items common to other services in the .NET My Services model, as described above in the common system section of the present application, and is extended to include service-specific global information by the following:  
     [0149] This schema outline in the table below illustrates the layout and meaning of the information for the myLists service and in the myLists system document:  
               TABLE                       Common /MyLists/ system                                    &lt; sys:system    changeNumber     =“ ...” instanceId=“ ...”                         xmlns:hs=“ http://schemas.microsoft.com/hs/2001/10/core”           xmlns:sys=“ http://schemas.microsoft.com/hs/2001/10The /MyLists/system” &gt; 1 1             &lt; hs:systemVersion    changeNumber     =“ ...”    id   =“ ...”    creator   =“ ...”&gt; 1 1                           &lt;hs:version majorVersion=“ ...” minorVersion=“ ...” buildNumber=“ ...” qfe=“ ...” &gt; 1..1                           &lt;hs:productReleaseName&gt; 1 1 &lt;/hs:productReleaseName&gt;           &lt;hs:productImplementationName&gt; 1 1 &lt;/hs:productImplementationName&gt;                         &lt;/hs:version&gt;           &lt;hs:buildDate&gt; 1 1 &lt;/hs:buildDate&gt;           &lt;hs:buildDetails machine=“ ...” branch=“ ...” type=“ ...” official=“ ...” &gt; 1 1 &lt;/hs:buildDetails&gt;                         &lt;/ hs:systemVersion &gt;           &lt; hs:roleMap    changeNumber     =“ ...”    id   =“ ...”    creator   =“ ...” &gt; 1 1                           &lt;hs:scope    id   =“ ...” &gt; 0 unbounded                           &lt;hs:name xml:lang=“ ...” dir=“ ...” &gt; 0 unbounded &lt;/hs:name&gt;           &lt;hs:shape base=“ ...” &gt; 1 1                           &lt;hs:include select=“ ...” &gt; 0 unbounded &lt;/hs:include&gt;           &lt;hs:exclude select=“ ...” &gt; 0 unbounded &lt;/hs:exclude&gt;                         &lt;/hs:shape&gt;                         &lt;/hs:scope&gt;           &lt;hs:roleTemplate name=“ ...” priority=“ ...” &gt; 0 unbounded                           &lt;hs:fullDescription xml:lang=“ ...” dir=“ ...” &gt; 0 1 &lt;/hs:fullDescription&gt;           &lt;hs:method name=“ ...” scopeRef=“ ...” &gt; 0 unbounded &lt;/hs:method&gt;                         &lt;/hs:roleTemplate&gt;                         &lt;/ hs:roleMap &gt;           &lt; hs:methodMap    changeNumber     =“ ...”    id   =“ ...”    creator   =“ ...” &gt; 1 1                           &lt;hs:method name=“ ...” &gt; 0 unbounded    {any} &lt;/hs:method&gt;                         &lt;/ hs:methodMap &gt;           &lt; hs:schemaMap    changeNumber     =“ ...”    id   =“ ...”    creator   =“ ...” &gt; 1 .1                           &lt;hs:schema namespace=“ ...” schemaLocation=“ ...” alias=“ ...” &gt; 0 unbounded    {any} &lt;/hs:schema&gt;                         &lt;/ hs:schemaMap &gt;           &lt; hs:wsdlMap    changeNumber     =“ ...”    id   =“ ...”    creator   =“ ...” &gt; 1 1                           &lt;hs:wsdl wsdlLocation=“ ...” &gt; 0 unbounded    {any} &lt;/hs:wsdl&gt;           &lt;hs:disco discoLocation=“ ...” &gt; 0 unbounded    {any} &lt;/hs:disco&gt;           &lt;hs:wsil wsilLocation=“ ...” &gt; 0 unbounded    {any} &lt;/hs:wsil&gt;                         &lt;/ hs:wsdlMap &gt;                         &lt;/ any &gt;                 &lt;/sys:system&gt;                  
 
     [0150] The meaning of the attributes and elements shown in the preceding sample document outline follow, beginning with /system (minOccurs=1 maxOccurs=1), the element that encapsulates a system document common to the various services. Although each service has its own system document, the common system document attributes and elements are described once, for purposes of simplicity, with service-specific system document attributes and elements specified for each service, below. The /system/@changeNumber (minOccurs=0 maxOccurs=1) attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0151] The /system/@instanceId (string minOccurs=0 maxOccurs=1) attribute is a unique identifier typically assigned to the root element of a service. It is a read-only element and assigned by the .NET My Services system when a user is provisioned for a particular service.  
     [0152] The /system/systemVersion (minOccurs=1 maxOccurs=1) element defines version information describing this instance of the .NET MyServices service. The /systemVersion/@changeNumber (minOccurs=0 maxOccurs=1) changeNumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications; attempts to write this attribute are silently ignored, (e.g., without generating an error).  
     [0153] The /system/systemVersion/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored.  
     [0154] The /system/systemVersion/@creator (string minOccurs=0 maxOccurs=1) attribute identifies the creator in terms of userId, appId, and platformId of the node. The /system/systemVersion/version (minOccurs=1 maxOccurs=1) element defines major, minor, and build number version information. The /system/systemVersion/version/@majorVersion (string minOccurs=0 maxOccurs=1) attribute specifies the major version number of the .NET MyServices service.  
     [0155] The /system/systemVersion/version/@minorVersion (string minOccurs=0 maxOccurs=1) attribute specifies the minor version number of the .NET MyServices service. The /system/systemVersion/version/@buildNumber (string minOccurs=0 maxOccurs=1) attribute specifies the buildNumber of the .NET MyServices service. The /system/systemVersion/version/@qfe (string minOccurs=0 maxOccurs=1) attribute specifies the qfe version number of the .NET MyServices service. The /system/systemVersion/version/productReleaseName (string minOccurs=1 maxOccurs=1) element defines the major product release string (as in .NET My Services Beta 1, and so on). The /system/systemVersion/version/productImplementationName (anyURI minOccurs=1 maxOccurs=1) element defines the class of the service to differentiate between different implementations.  
     [0156] The /system/systemVersion/buildDate (dateTime minOccurs=1 maxOccurs=1) element defines the date and time that the .NET My Services system was built. The time is in UTC (Z relative) form. The /systemVersion/buildDetails (minOccurs=1 maxOccurs=1) element defines details of the build including the machine that generated the build, the branch id of the software that contributed to the build, the type of build (chk/fre), and if the build was generated by an official build release process.  
     [0157] The /system/systemVersion/buildDetails/@machine (string minOccurs=0 maxOccurs=1) attribute specifies the machine that generated the build. The system/systemVersion/buildDetails/@branch (string minOccurs=0 maxOccurs=1) attribute specifies the software branch id for the source code that contributed to this build. The /system/systemVersion/buildDetails/@type (string minOccurs=0 maxOccurs=1) attribute specifies the type of build. A value of chk indicates that this is a checked or debug build. A value of fre indicates that this is a retail build. The /system/systemVersion/buildDetails/@official (string minOccurs=0 maxOccurs=1) attribute indicates that the build was produced by an official build process (value of yes), or an unofficial process (value of no).  
     [0158] The /system/roleMap (minOccurs=1 maxOccurs=1) element encapsulates all the elements that make up a roleMap, which include document class relative roleTemplate, priority, name, method, and per-method scope. An individual roleTemplate defines the maximum scope of information, and the allowable methods used to access that information for each request mapped into the template. The /system/roleMap/@changeNumber (minOccurs=0 maxOccurs=1) changeNumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored. The /system/roleMap/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored.  
     [0159] The /system/roleMap/@creator (string minOccurs=0 maxOccurs=1) attribute identifies the creator in terms of userId, appId, and platformId of the node. The /system/roleMap/scope (minOccurs=0 maxOccurs=unbounded) element defines a scope which may be referred to by roles within this roleMap to indicate what portions of the document are visible to this role for the specified method.  
     [0160] The /system/roleMap/scope/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored. The /system/roleMap/scope/name (string minOccurs=0 maxOccurs=unbounded) node includes the /system/roleMap/scope/name/@xml:lang (minOccurs=1 maxOccurs=1) required attribute, which is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /system/roleMap/scope/name/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the default layout direction for the localized string. Valid values are rtl (right to left), and ltr (left to right).  
     [0161] The /system/roleMap/scope/shape (minOccurs=1 maxOccurs=1) comprises a shape that defines the node set that is visible through the document when operating through this shape element. The /system/roleMap/scope/shape/@base (string minOccurs=0 maxOccurs=1) attribute specifies the initial set of nodes visible through the shape. A value of t indicates that the shape is initialized to include all possible nodes relative to the shape that is currently in effect. For instance, each role defines a scope containing a shape. When defining a shape for a role, the value t indicates all possible nodes available in the specified document for this role. When defining a shape in an ACL entry, a value of t means all of the nodes visible in the shape for the computed role. When using a shape in a data language (e.g., query, insert, replace and so on) operation, a value of t indicates all of the possible nodes selected by the data language operation (relative to the ACL shape which itself is relative to the role&#39;s shape). The value nil indicates the opposite of t, which is the empty node set. Nodes from this set may then be included into the shape.  
     [0162] The /system/roleMap/scope/shape/include (minOccurs=0 maxOccurs=unbounded) element specifies the set of nodes that should be included into the shape relative to the possible set of nodes indicated by the base attribute. The /system/roleMap/scope/shape/include/@select (string minOccurs=0 maxOccurs=1) item specifies an XPATH expression that selects a set of nodes relative to the externally established context. The expression can never travel outside the node-set established by this externally established current context. The expression may match zero or more nodes, and the operation manipulates all selected nodes. The minOccurs and maxOccurs attributes are optional and place restrictions and limitations on the number of nodes selected.  
     [0163] The /system/roleMap/scope/shape/exclude (minOccurs=0 maxOccurs=unbounded) element specifies the set of nodes that should be excluded from the shape relative to the possible set of nodes indicated by the base attribute. The /system/roleMap/scope/shape/exclude/@select (string minOccurs=0 maxOccurs=1) item specifies an XPATH expression that selects a set of nodes relative to the externally established context. The expression can never travel outside the node-set established by this externally established current context. The expression may match zero (0) or more nodes, and the operation manipulates all selected nodes. The minOccurs and maxOccurs attributes are optional and place restrictions and limitations on the number of nodes selected. The /system/roleMap/roleTemplate (minOccurs=0 maxOccurs=unbounded) element encapsulates the definition of a role. The attribute set for this element includes the document class that this roleTemplate refers to, the name of the roleTemplate, and the priority of the roleTemplate.  
     [0164] The /system/roleMap/roleTemplate/@name (string minOccurs=0 maxOccurs=1) element specifies the name of the role. The /system/roleMap/roleTemplate/@priority (int minOccurs=0 maxOccurs=1) element specifies the priority of the roleTemplate which is used to select that actual roleTemplate when the role evaluation determines that the subject maps to multiple roleTemplates.  
     [0165] The /system/roleMap/roleTemplate/fullDescription (string minOccurs=0 maxOccurs=1) element contains a description of this role template which specifies the capabilities a caller will have when accessing information through this role. The /system/roleMap/roleTemplate/fullDescription/@xml:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /system/roleMap/roleTemplate/fullDescription/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the default layout direction for the localized string. Valid values are rtl (right to left), and ltr (left to right).  
     [0166] The /system/roleMap/roleTemplate/method (minOccurs=0 maxOccurs=unbounded) element specifies the methods available within this roleTemplate by name, and by scope. When a subject maps to a roleTemplate, the method in the request must match one of these elements for the message to continue to flow. If the method exists, the data available to the method is a function of the scope referenced by this method combined with an optional scope referenced by the role defined in the roleList.  
     [0167] The /system/roleMap/roleTemplate/method/@name (string minOccurs=0 maxOccurs=1) element specifies the name of the method. The /system/roleMap/roleTemplate/method/@scopeRef (string minOccurs=0 maxOccurs=1) attribute specifies the scope within this document that is in effect for this method. The /system/methodMap (minOccurs=1 maxOccurs=1) element defines the methodMap. While in most cases, the roleMap section contains a definitive list of methods, these methods are likely to be scattered about the roleMap in various templates. This section contains the definitive non-duplicated list of methods available within the service.  
     [0168] The /system/methodMap/@changeNumber (minOccurs=0 maxOccurs=1) changeNumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0169] The /system/methodMap/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored. The /system/methodMap/@creator (string minOccurs=0 maxOccurs=1) attribute identifies the creator in terms of userId, appId, and platformId of the node.  
     [0170] The /system/methodMap/method (minOccurs=0 maxOccurs=unbounded) element defines a method that is available within this service. The /system/methodMap/method/@name (string minOccurs=0 maxOccurs 1) attribute specifies the name of a method available within the service. The /system/methodMap/method/{any} (minOccurs=0 maxOccurs=unbounded) provides for extensibility. The /system/schemaMap (minOccurs=1 maxOccurs=1) element defines the various schema&#39;s that define the data structures and shape of information managed by this service. Each schema is defined by its namespace URI, its location, and a preferred namespace alias.  
     [0171] The /system/schemaMap/@changeNumber (minOccurs=0 maxOccurs=1) changeNumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0172] The /system/schemaMap/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored.  
     [0173] The /system/schemaMap/@creator (string minOccurs=0 maxOccurs=1) attribute identifies the creator in terms of userId, appId, and platformId of the node. The /system/schemaMap/schema (minOccurs=0 maxOccurs=unbounded) element defines a schema which defines data-structures and the shape of information managed by this service. Multiple schema elements exist for each service, once for each logical grouping of information exposed by the service. The /system/schemaMap/schema/@namespace (anyURI minOccurs=0 maxOccurs=1) attribute specifies the namespace URI of this schema. The /system/schemaMap/schema/@schemaLocation (anyURI minOccurs=0 maxOccurs=1) attribute specifies the location (in the form of a URI) of the resource containing schema. When a schema is reachable through a variety of URIs, one schema element will exist for each location.  
     [0174] The /system/schemaMap/schema/@alias (string minOccurs=0 maxOccurs=1) attribute specifies the preferred alias that should be used if possible when manipulating information covered by this schema in the context of this service. The /system/schemaMap/schema/{any} (minOccurs=0 maxOccurs=unbounded) provides for extensibility. The /system/wsdlMap (minOccurs=1 maxOccurs=1) element defines the wsdlMap for this service. This map includes the location of WSDL documents, DISCO documents, and WSIL documents for this web service. These documents are used by applications to understand the format of messages that may be sent to the various services. The /system/wsdlMap/@changeNumber (minOccurs=0 maxOccurs=1) changeNumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0175] The /system/wsdlMap/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored. The /system/wsdlMap/@creator (string minOccurs=0 maxOccurs=) attribute identifies the creator in terms of userId, appId, and platformId of the node.  
     [0176] The /system/wsdlMap/wsdl (minOccurs=0 maxOccurs=unbounded) element is used to specify the location of a WSDL file for this service. Multiple entries may exist pointing to the same file hosted in multiple locations, or to variations on the content within the WSDL files.  
     [0177] The /system/wsdlMap/wsdl/@wsdlLocation (anyURI minOccurs=0 maxOccurs=1) attribute is a URI that specifies the location of the WSDL file. The /system/wsdlMap/wsdl/{any} (minOccurs=0 maxOccurs=unbounded) provides for extensibility.  
     [0178] The /system/wsdlMap/disco (minOccurs=0 maxOccurs=unbounded) element is used to specify the location of a DISCO (web-services discovery) file for this service. Multiple entries may exist pointing to the same file hosted in multiple locations, or to variations on the content within the DISCO files. The /system/wsdlMap/disco/@discoLocation (anyURI minOccurs=0 maxOccurs=1) attribute is a URI that specifies the location of the DISCO file. The /system/wsdlMap/disco/{any} (minOccurs=0 maxOccurs=unbounded) provides extensibility. The /system/wsdlMap/wsil (minOccurs=0 maxOccurs=unbounded) element is used to specify the location of a WSIL file for this service. Multiple entries may exist pointing to the same file hosted in multiple locations, or to variations on the content within the WSIL files. The /system/wsdlMap/wsil/@wsilLocation (anyURI minOccurs=0 maxOccurs=1) attribute is a URI that specifies the location of the WSIL file. The /system/wsdlMap/wsil/{any} (minOccurs=0 maxOccurs=unbounded) provides extensibility.  
               TABLE                       myLists / system                                    &lt; sys:system &gt;                         :           :  see common myLists / system above           :           &lt; sys:list    idName     =“...”    changeNumber   =“...”    id   =“...”    creator   =“...”&gt; 0 unbounded                           &lt;m:cat ref=“...”&gt; 0 unbounded &lt;/m:cat&gt;           &lt;m:listRef ref=“...” order=“...”&gt; 0 unbounded &lt;/m:listRef&gt;           &lt;m:title xml:lang=“...” dir=“...”&gt; 0 unbounded &lt;/m:title&gt;           &lt;m:description xml:lang=“...” dir=“...”&gt; 0 unbounded &lt;/m:description&gt;           &lt;m:status&gt; 0 1 &lt;/m:status&gt;             {any}                           &lt;/ sys:list &gt;             {any}                   &lt;/ sys:system &gt;                  
 
     [0179] The /system/list (minOccurs=0 maxOccurs=unbounded) element defines a list which includes categorization of the list, a localized name for the list, a brief description of the list, and any other application specific properties contained within the any block(s). The /system/list/@idName (string minOccurs=0 maxOccurs=1) attribute specifies the name of the list that can be used in a list reference. Note that list references are coded as URIs in both absolute, and myLists relative forms. This attribute is the value of the fragment identifier from those URIs. For example, a listRef/@ref value of “system#todo” would map to a list element whose @idName attribute was todo, and that is located in the system document of the myLists service.  
     [0180] The /system/list/@changeNumber (minOccurs=0 maxOccurs=1) changeNumber attribute is designed to facilitate caching of the element and its descendants. This attribute is assigned to this element by the .NET My Services system. The attribute is read-only to applications. Attempts to write this attribute are silently ignored.  
     [0181] The /system/list/@id (minOccurs=0 maxOccurs=1) attribute is a globally unique ID assigned to this element by .NET My Services. Normally, .NET My Services will generate and assign this ID during an insertRequest operation, or possibly during a replaceRequest. Application software can override this ID generation by specifying the useClientIds attribute in the request message. Once an ID is assigned, the attribute is read-only and attempts to write it are silently ignored.  
     [0182] The /system/list/@creator (string minOccurs=0 maxOccurs=1) attribute identifies the creator in terms of userId, appId, and platformId of the node.  
     [0183] The /system/list/cat (minOccurs=0 maxOccurs=unbounded) element is used to categorize the element that contains it by referencing a global category definition in either the .NET Categories service system document or an external resource containing category definitions, or by referencing an identity centric category definition in the content document of the .NET Categories service for a particular puid.  
     [0184] The /system/list/cat/@ref (anyURI minOccurs=0 maxOccurs=1) attribute references a category definition (&lt;catDef/&gt;) element using the rules outlined in the myCategories section above. The /system/list/listRef (minOccurs=0 maxOccurs=unbounded) element specifies the lists that this item is considered contained within. Note that it is valid to have a free-form list item that is not considered to be in part of any list which is why this element is minOccurs=0.  
     [0185] The /system/list/listRef/@ref (anyURI minOccurs=0 maxOccurs=1) attribute contains the name of a list element encoded as a URI. The URI follows encoding rules similar to those used in cat/catDef linkage:  
     [0186] system#name-of-list  
     [0187] The list (definition) being referenced is located in the system document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. For example, the listRef of &lt;listRef ref=“system#todo”/&gt; is a reference to the list definition whose list/@idName value is “todo”, and that this list definition is located in the system document of the .NET Lists service i.e.&lt;list name=“todo”/&gt;.  
     [0188] content[?puid=puid-value]#name-of-list  
     [0189] The list definition being referenced is located in the content document of the .NET Lists service, and its list/@idName attribute is “name-of-list”. The instance of the .NET Lists service (i.e., the puid of the service) is implied by the context of the reference. This may be made explicit by inserting ?puid=puid-value to the URI, and when this is done, it means the content document of the .NET Lists service whose puid is “puid-value” holds the list definition. For example, the list reference of &lt;listRef ref=“content#bellSqareShopping”/&gt; is a reference to the list definition whose list/@idName value is “bellSquareShopping”, and that this list definition is located in the content document of the .NET List service for the current puid i.e.&lt;list name=“bellSquareShopping”/&gt;.  
     [0190] y-uri#name-of-list  
     [0191] The list definition being referenced is located in an external (to .NET My Services) resource. The “any-uri” portion of the reference refers to a resource containing the list element whose @idName attribute matches the “name-of-list”. The mapping between the “any-uri” portion of the reference and an XML document containing the list elements is a function of the “any-uri”. By convention, this uri is the name of an XML document containing those elements. The purpose of this reference form is to allow and support a free form set of extended list definitions that are global and available to all. For example, the list reference of &lt;listRef ref=“http://schemas.xyz.com/im/globalLists.xml#xyzStuff”/&gt; is a reference to the list definition whose list/@idName value is “xyzStuff”, and that this list definition is located in an external resource located at “http://schemas.xyz.com/im/globalLists.xml”. Note that it is expected that list definitions will exist in the appropriate locations, but there is no requirement or enforcement of this.  
     [0192] The /system/list/listRef/@order (int minOccurs=0 maxOccurs=1) attribute contains an optional numeric order for the containing item relative to this list. Since an item (or even a list) may logically be contained within multiple lists, the order of the item is attached to the list reference so that an item&#39;s order can vary based on the list that it is contained within.  
     [0193] The /system/list/title (string minOccurs=0 maxOccurs=unbounded) element specifies the title of the list. The /system/List/title/@xml:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. Te /system/list/title/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the default layout direction for the localized string. Valid values are rtl (right to left), and ltr (left to right).  
     [0194] The /system/list/description (string minOccurs=0 maxOccurs=unbounded) element specifies a more detailed description of the list. The /system/List/description/@xml:lang (minOccurs=1 maxOccurs=1) required attribute is used to specify an ISO 639 language code or an ISO 3166 country code as described in RFC 1766. The value of this attribute indicates the language type of the content within this element. The /system/list/description/@dir (string minOccurs=0 maxOccurs=1) optional attribute specifies the base direction of directionally neutral text. Possible values include rtl (right to left), or ltr (left to right).  
     [0195] The /system/list/status (anyURI minOccurs=0 maxOccurs=1) contains a status value for a list the optional status of that list. This elements value is coded as a category reference and follows the same rules as found in the usage of cat/@ref. The value may reference a category in the myCategories system document, a private status value in the user&#39;s myCategories content document, or an external category definition. It is expected that pre-defined system category values in the “system#status” category will be used and this would mean that expected values for this element include, system#notStarted, system#inProgress, system#completed, system#waiting and system#defered.  
     [0196] A node select of “//sys:catDef[hs:cat[@ref=‘system#status’]” will locate all definitions for system defined status values.  
     [0197] The /system/list/{any} (minOccurs=0 maxOccurs=unbounded) and /system/{any} (minOccurs=0 maxOccurs=unbounded) fields provide extensibility as discussed above.  
     [0198] myLists Methods  
     [0199] The myLists service supports the standard methods query, insert, replace, delete, and update.  
     [0200] As can be seen from the foregoing detailed description, there is provided a schema-based myLists service that allows users to access their document data based on their identities and corresponding roles with respect to the data. The schema-based myLists service provides documents data access independent of the application program and device, and in a centrally-accessible location such as the Internet. The schema-based myLists service is extensible to handle extended documents information.  
     [0201] While the invention is susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention.