Facilitating mobile device awareness of the availability of new or updated server-side applications

COPYRIGHT NOTICE

0001A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by any one of the patent document or patent disclosure, as it appears in a Patent Office patent file or records, but otherwise reserves all copyright rights whatsoever.

FIELD OF THE INVENTION

0002The present invention relates to software, devices and methods allowing varied mobile devices to interact with server side software applications, and more particularly, to software, devices and methods for facilitating mobile device awareness of the availability of new or updated server-side applications.

BACKGROUND OF THE INVENTION

0003Wireless connectivity is a feature of the modern telecommunications environment. An increasing range of people are using a wide variety of wireless data networks to access corporate data applications.

0004However, there are numerous competing mobile devices (i.e. wireless communications devices) that can be used to achieve this. Each device has its own operating system and its own display characteristics. Operating systems are not mutually compatible, nor are the display characteristics—some are color, some are black and white, some are text-only, and some are pictorial.

0005At the same time, an increasing number of mobile device users are people without a technical background or high level of educational achievement. Such people are often intimidated by the need to run complex installation programs. Furthermore, at present, such installation programs generally depend on cable connections to a personal computer by the means of a ‘cradle’ or other such device.

0006U.S. Patent Publication No. US 2003/0060896, which is hereby incorporated by reference hereinto, discloses a mechanism allowing server-side applications to be presented at multiple wireless devices with minimal modification of the application at the server. As disclosed, the manner in which an application is presented at a mobile device is defined by a text based application definition file. The definition file describes how an application is to be presented at mobile device; the format of transactions over the wireless network; and a format of data related to the application to be stored at the mobile device. A virtual machine software component at the mobile device interprets the definition file and presents an interface to the application in accordance with the definition file. Conveniently, the application definition file may be independent of the particular type of mobile device, while virtual machine software components specific to the mobile device may be created.

0007As is also disclosed in U.S. Patent Publication No. US 2003/0060896, a mobile device may interrogate a middleware server to determine which applications are available to that device. Unfortunately, such an arrangement may have certain shortcomings. In particular, a mobile device only becomes aware of the applications available to it by actively querying the middleware server. No provision exists for notifying the mobile device of the availability of a new application or updated version of an existing application. As a result, the set of applications capable of use at the mobile device may become outdated in relation to the set of applications which are potentially available for use at the mobile device.

0008Accordingly, there is a need for facilitating mobile device awareness of new or updated server-side applications.

SUMMARY OF THE INVENTION

0009To facilitate wireless communication device awareness of the availability of new or updated server-side applications, in response to either of a new application being made available at a server or an updated version of an application being made available at a server, a message is transmitted over a wireless connection to a set of wireless communications devices indicating that the new or updated application is available. The notification may be displayed on each of the mobile devices in the set. A device user may choose to register for the new or updated application on the basis of the notification. Notification may be performed when an application has been added to a group of applications to which access is provided as a whole. Notification at a particular wireless communications device may be conditional upon a grant of access by the device to said group of applications.

0010In one aspect of the present invention, there is provided a method of facilitating wireless communication device awareness of the availability of new or updated server-side applications, said method comprising: in response to either of a new application being made available at a server or an updated version of an application being made available at a server, transmitting a message over a wireless connection to a set of wireless communications devices indicating that said new or updated application is available.

0011In another aspect of the present invention, there is provided a server comprising a processor and memory in communication with said processor storing machine-executable code adapting said server to: in response to either of a new application being made available at said server or an updated version of an application being made available at said server, transmit a message over a wireless connection to a set of wireless communications devices indicating that said new or updated application is available.

0012In a further aspect of the present invention, there is provided a server comprising a processor and memory in communication with said processor storing machine-executable code adapting said server to: in response to either of a new application being made available at said server or an updated version of an application being made available at said server, transmit a message over a wireless connection to a set of wireless communications devices indicating that said new or updated application is available.

0013Other aspects and features of the present invention will become apparent to those of ordinary skill in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

0014In the figures which illustrate by way of example only, embodiments of the present invention,

0015<figref idref="DRAWINGS">FIG. 1</figref> schematically illustrates a mobile device, exemplary of an embodiment of the present invention, including virtual machine software, further exemplary of an embodiment of the present invention;

0016<figref idref="DRAWINGS">FIG. 2</figref> further illustrates the organization of exemplary virtual machine software at the mobile device of <figref idref="DRAWINGS">FIG. 1</figref>;

0017<figref idref="DRAWINGS">FIG. 3</figref> illustrates an operating environment for the device of <figref idref="DRAWINGS">FIG. 1</figref>;

0018<figref idref="DRAWINGS">FIG. 4</figref> illustrates the structure of example application definitions stored at a server of <figref idref="DRAWINGS">FIG. 2</figref> used by the device of <figref idref="DRAWINGS">FIG. 1</figref>;

0019<figref idref="DRAWINGS">FIG. 5</figref> schematically illustrates the formation of application definition files at a middleware server of <figref idref="DRAWINGS">FIG. 2</figref>;

0020<figref idref="DRAWINGS">FIG. 6</figref> schematically illustrates the middleware server of <figref idref="DRAWINGS">FIG. 2</figref>, exemplary of an embodiment of the present invention, including an application definitions database, further exemplary of an embodiment of the present invention;

0021<figref idref="DRAWINGS">FIG. 7</figref> is a flow diagram (also referred to as a sequence diagram) illustrating the exchange of sample messages passed between a mobile device, middleware server and application server of <figref idref="DRAWINGS">FIG. 2</figref>;

0022<figref idref="DRAWINGS">FIG. 8</figref> is a sequence diagram illustrating operation for notifying a mobile device of the availability of a new or updated application;

0023<figref idref="DRAWINGS">FIG. 9</figref> illustrates an exemplary GUI by which new or updated application notification may be triggered at a middleware server;

0024<figref idref="DRAWINGS">FIG. 10</figref> illustrates the format and content of an exemplary message which may be used for purposes of notifying mobile devices of new or updated applications;

0025<figref idref="DRAWINGS">FIG. 11</figref> illustrates the format and content of an exemplary general “application notify” message;

0026<figref idref="DRAWINGS">FIGS. 12-14</figref> illustrate steps performed at a mobile device under control of virtual machine software of <figref idref="DRAWINGS">FIG. 2</figref>;

0027<figref idref="DRAWINGS">FIG. 15</figref> illustrates the format of messages exchanged in the message flow of <figref idref="DRAWINGS">FIG. 7</figref>;

0028<figref idref="DRAWINGS">FIG. 16</figref> illustrates a presentation of a user interface for a sample application at a mobile device;

0029<figref idref="DRAWINGS">FIG. 17</figref> illustrates a sample portion of an application definition file defining a user interface illustrated in <figref idref="DRAWINGS">FIG. 16</figref>;

0030<figref idref="DRAWINGS">FIG. 18</figref> illustrates the format of a message formed in accordance with the sample portion of an application definition file of <figref idref="DRAWINGS">FIG. 17</figref>;

0031<figref idref="DRAWINGS">FIG. 19A</figref> illustrates a sample portion of an application definition file defining a local storage at a mobile device;

0032<figref idref="DRAWINGS">FIG. 19B</figref> schematically illustrates local storage in accordance with <figref idref="DRAWINGS">FIG. 19A</figref>;

0033<figref idref="DRAWINGS">FIG. 19C</figref> illustrates how locally stored data is updated by a sample message in accordance with the sample portion of an application file definition of <figref idref="DRAWINGS">FIG. 19A</figref>; and

0034FIGS. <b>20</b>A-<b>20</b>LLL contain Appendix “A” detailing example XML entities understood by the virtual machine software of the mobile device of <figref idref="DRAWINGS">FIG. 1</figref>.

DETAILED DESCRIPTION

0035<figref idref="DRAWINGS">FIG. 1</figref> illustrates a mobile device <b>10</b>, exemplary of an embodiment of the present invention. Mobile device <b>10</b> may be any conventional mobile device, modified to function in manners exemplary of the present invention. As such, mobile device <b>10</b> includes a processor <b>12</b>, in communication with a network interface <b>14</b>, storage memory <b>16</b>, and a user interface <b>18</b> typically including a keypad and/or touch-screen. Network interface <b>14</b> enables device <b>10</b> to transmit and receive data over a wireless network <b>22</b>. Mobile device <b>10</b> may be, for example, be a Research in Motion (RIM) two-way paging device, a WinCE based device, a PalmOS device, a WAP enabled mobile telephone, or the like. Memory <b>16</b> of device <b>10</b> stores a mobile operating system such as the PalmOS, or WinCE operating system software <b>20</b>. Operating system software <b>20</b> typically includes graphical user interface and network interface software having suitable application programmer interfaces (“API”s) for use by other applications executing at device <b>10</b>.

0036Memory at device <b>10</b> further stores virtual machine software <b>24</b>, exemplary of an embodiment of the present invention. Virtual machine software <b>24</b>, when executed by mobile device <b>10</b> enables device <b>10</b> to present an interface for server side applications provided by a middleware server, described below. Specifically, virtual machine software <b>24</b> interprets a text application definition file defining a user interface <b>18</b> controlling application functionality, and the display format (including display flow) at device <b>10</b> for a particular server-side application; the format of data to be exchanged over the wireless network for the application; and the format of data to be stored locally at device <b>10</b> for the application. Virtual machine software <b>24</b> uses operating system <b>20</b> and associated APIs to interact with device <b>10</b>, in accordance with the received application definition file. In this way, device <b>10</b> may present interfaces for a variety of applications, stored at a server. From the perspective of operating system <b>20</b>, virtual machine software <b>24</b> is viewed as another application resident at device <b>10</b>. Moreover, multiple wireless devices each having a similar virtual machine software <b>24</b> may use a common server side application in combination with an application definition, to present a user interface and program flow specifically adapted for the device.

0037As such, and as will become apparent, the exemplary virtual machine software <b>24</b> is specifically adapted to work with the particular mobile device <b>10</b>. Thus if device <b>10</b> is a RIM Blackberry device, virtual machine software <b>24</b> is a RIM virtual machine. Similarly, if device <b>10</b> is a PalmOS or WinCE device, virtual machine software <b>24</b> would be a PalmOS or a WinCE virtual machine. As further illustrated in <figref idref="DRAWINGS">FIG. 1</figref>, virtual machine software <b>24</b> is capable of accessing local storage <b>26</b> at device <b>10</b>.

0038As detailed below, an exemplary application definition file may be formed using a mark-up language, like XML. In accordance with an embodiment of the present invention, defined XML entities are understood by the virtual machine software <b>24</b>. Defined XML entities are detailed in Appendix “A” hereto (the AIRIX Markup Language (ARML) Specification) and Appendix “A” of U.S. Patent Publication No. 2003/0060896. ARML is an XML markup language used in the present embodiment. The defined XML entities are interpreted by the virtual machine software <b>24</b>, and may be used as building blocks to present server-side applications at mobile device <b>10</b>, as detailed herein.

0039Specifically, as illustrated in <figref idref="DRAWINGS">FIG. 2</figref>, virtual machine software <b>24</b> includes a conventional XML parser <b>61</b>; an event handler <b>65</b>; a screen generation engine <b>67</b>; and object classes <b>69</b> corresponding to XML entities supported by the virtual machine software <b>24</b>, and possibly contained within an application definition file <b>28</b>. Supported XML entities are detailed in Appendix “A” hereto. A person of ordinary skill will readily appreciate that those XML entities identified in Appendix “A” are exemplary only, and may be extended, or shortened as desired.

0040XML parser <b>61</b> may be formed in accordance with the Document Object Model, or DOM, available at www.w3.org/DOM/, which is hereby incorporated by reference hereinto. Parser <b>61</b> enables virtual machine software <b>24</b> to read an application definition file. Using the parser, the virtual machine software <b>24</b> may form a binary representation of the application definition file for storage at the mobile device, thereby eliminating the need to parse text each time an application is used. Parser <b>61</b> may convert each XML tag contained in the application definition file, and its associated data to tokens, for later processing. As will become apparent, this may avoid the need to repeatedly parse the text of an application definition file.

0041Screen generation engine <b>67</b> displays initial and subsequent screens at the mobile device, in accordance with an application definition <b>28</b>, as detailed below.

0042Event handler <b>65</b>; of virtual machine software <b>24</b> allows device <b>10</b> under control of virtual machine software <b>24</b> to react to certain external events. Example events include user interaction with presented screens or display elements, incoming messages received from a wireless network, or the like.

0043Object classes <b>69</b> also form part of virtual machine <b>24</b> and define objects that allow device <b>10</b> to process each of the supported XML entities at the mobile device. Each of object classes <b>69</b> includes attributes used to store parameters defined by the XML file, and functions allowing the XML entity to be processed at the mobile device, as detailed in Appendix “A”, for each supported XML entity. So, as should be apparent, supported XML entities are extensible. Virtual machine software <b>24</b> may be expanded to support XML entities not detailed in Appendix “A”. Corresponding object classes could be added to virtual machine software <b>24</b>.

0044As detailed below, upon invocation of a particular application at mobile device <b>10</b>, the virtual machine software <b>24</b> presents an initial screen based on the contents of the application definition <b>28</b> for the application. Screen elements are created by screen generation engine <b>67</b> by creating instances of corresponding object classes for defined elements, as contained within object classes <b>69</b>. The object instances are created using attributes contained in the application definition file <b>28</b>. Thereafter the event handler <b>65</b> of the virtual machine software <b>24</b> reacts to events for the application. Again, the event handler consults the contents of the application definition file for the application in order to properly react to events. Events may be reacted to by creating instances of associated “action” objects, from object classes <b>69</b> of virtual machine software <b>24</b>.

0045Similarly, object classes <b>69</b> of virtual machine software <b>24</b> further include object classes corresponding to data tables and network transactions defined in the Table Definition and Package Definition sections of Appendix “A”. At run time, instances of object classes corresponding to these classes are created and populated with parameters contained within application definition file, as required.

0046Using this general description, persons of ordinary skill in the art will be able to form virtual machine software <b>24</b> for any particular device. Typically, virtual machine software <b>24</b> may be formed using conventional object oriented programming techniques, and existing device libraries and APIs, as to function as detailed herein. As will be appreciated, the particular format of screen generation engine <b>67</b>, object classes <b>69</b> will vary depending on the type of virtual machine software, its operating system and API available at the device. Once formed, a machine executable version of virtual machine software <b>24</b> may be loaded and stored at a mobile device, using conventional techniques. It can be embedded in ROM, loaded into RAM over a network, or from a machine readable medium.

0047Although, in the preferred embodiment the virtual machine software <b>24</b> and software forming object classes <b>29</b> are formed using object oriented structures, persons of ordinary skill will readily appreciate that other approaches could be used to form suitable virtual machine software. For example, object classes <b>69</b> forming part of the virtual machine could be replaced by equivalent functions, data structures or subroutines formed using a conventional (i.e. non-object oriented) programming environment. Operation of virtual machine software <b>24</b> under control of an application definition containing various XML definitions exemplified in Appendix “A” is further detailed below.

0048<figref idref="DRAWINGS">FIG. 3</figref> illustrates the operating environment for a mobile device <b>10</b>. Further example mobile devices <b>30</b>, <b>32</b> and <b>34</b> are also illustrated in <figref idref="DRAWINGS">FIG. 3</figref>. These mobile devices <b>30</b>, <b>32</b> and <b>34</b> are similar to device <b>10</b> and also store and execute virtual machine software exemplary of an embodiment of the present invention.

0049Virtual machine software like that stored at device <b>10</b>, executes on each mobile device <b>10</b>, <b>30</b>, <b>32</b>, <b>34</b>, and communicates with a middleware server <b>44</b> by way of example wireless networks <b>36</b> and <b>38</b> and network gateways <b>40</b> and <b>42</b>. Example gateways <b>40</b> and <b>42</b> are generally available as a service for those people wishing to have data access to wireless networks. Wireless networks <b>36</b> and <b>38</b> are further connected to one or more computer data networks, such as the Internet and/or private data networks by way of gateway <b>40</b> or <b>42</b>. As will be appreciated, the invention may work with many types of wireless networks. Middleware server <b>44</b> is in turn in communication with a data network, that is in communication with wireless network <b>36</b> and <b>38</b>. The communication used for such communication is via TCP/IP over an HTTP transport. As could be appreciated, other network protocols such as X.25 or SNA could equally be used for this purpose.

0050At least three categories of communication between middleware server <b>44</b> and devices <b>10</b>, <b>30</b>, <b>32</b>, and <b>34</b> exist. First, virtual machine software <b>24</b> at each device may query middleware server <b>44</b> for a list of applications that a user of an associated mobile device <b>10</b>, <b>30</b>, <b>32</b> or <b>34</b> can make use of. If a user decides to use a particular application, device <b>10</b>, <b>30</b>, <b>32</b> or <b>34</b> can download a text description, in the form of an application definition file, for the application from the middleware server <b>44</b> over its wireless interface. As noted, the text description is preferably formatted using XML. Second, middleware server <b>44</b> may notify one or more of devices <b>10</b>, <b>30</b>, <b>32</b> and <b>34</b> of the availability of new applications or updated versions of existing applications at the application server so that a user of the mobile device(s) may decide whether or not it is desired to download a corresponding (new or updated) application definition file from the middleware server <b>44</b> so that the new or updated application may be used remotely. Third, virtual machine software <b>24</b> may send, receive, present, and locally store data related to the execution of applications, or its own internal operations. The format of exchanged data for each application is defined by an associated application definition file. Again, the exchanged data is formatted using XML, in accordance with the application definition file. As will become apparent, it is the second category of communication which is the focus of the present application.

0051Middleware server <b>44</b> stores text application definition files for those applications that have been enabled to work with the various devices <b>10</b>, <b>30</b>, <b>32</b>, and <b>34</b> using virtual machine software <b>24</b> in a pre-defined format understood by virtual machine software <b>24</b>. Software providing the functions of the middleware server <b>44</b>, in the exemplary embodiment is written in C#, using SQL Server or MySQL database.

0052As noted, text files defining application definitions and data may be formatted in XML. For example XML version 1.0, detailed in the XML version 1.0 specification third edition and available at www.w3.org/TR/2004/REC-xml-20040404, may be used. However, as will be appreciated by those of ordinary skill in the art, the functionality of storing XML description files is not dependent on the use of any given programming language or database system.

0053Each application definition file is formatted according to defined rules and uses pre-determined XML mark-up tags known by both virtual machine software <b>24</b>, and complementary middleware server software <b>68</b>. That is, each application definition file <b>26</b> is an XML data instance file which conforms to a predefined XML schema designed to support the execution of server-side applications at various types of mobile devices. Tags define XML entities used as building blocks to present an application at a mobile device. Knowledge of these rules, and an understanding of how each tag and section of text should be interpreted, allows virtual machine software <b>24</b> to process an XML application definition and thereafter execute an application, as described below. Virtual machine software <b>24</b> effectively acts as an interpreter for a given application definition file.

0054<figref idref="DRAWINGS">FIG. 4</figref> illustrates an example format for an XML application definition file <b>28</b>. As illustrated, the example application definition file <b>28</b> for a given device and application includes three components: a user interface definition section <b>48</b>, specific to the user interface for the device <b>10</b>, which defines the format of screen or screens for the application and how the user interacts with them and contains application flow control events and actions; a network transactions definition section <b>50</b> defining the format of data to be exchanged with the application; and a local data definition section <b>52</b> defining the format of data to be stored locally on the mobile device by the application.

0055Defined XML mark-up tags correspond to XML entities supported at a device, and are used to create an application definition file <b>28</b>. The defined tags may broadly be classified into three categories, corresponding to the three sections <b>48</b>, <b>50</b> and <b>52</b> of an application definition file <b>28</b>.

0056Example XML tags and their corresponding significance are detailed in Appendix “A”. As noted above, virtual machine software <b>24</b> at a mobile device includes object classes corresponding to each of the XML tags. At run time, instances of the objects are created as required.

0057Broadly, the following list includes example XML tags (i.e. XML elements) which may be used to define the user interface definition: <ul id="ul0001" list-style="none"><li id="ul0001-0001" num="0000"><ul id="ul0002" list-style="none"><li id="ul0002-0001" num="0058"> SCREEN—this defines a screen. A SCREEN tag pair contains the definitions of the user interface elements (buftons, radio buttons, and the like) and the events associated with the screen and its elements </li><li id="ul0002-0002" num="0059"> BUTTON—this tag defines a button and its associated attributes </li><li id="ul0002-0003" num="0060"> LIST—this tag defines a list box </li><li id="ul0002-0004" num="0061"> CHOICEBOX—this tag defines a choice item, that allows selection of a value from predefined list </li><li id="ul0002-0005" num="0062"> MENU—the application developer will use this tag to define a menu for a given screen </li><li id="ul0002-0006" num="0063"> EDITBOX—this tag defines an edit box </li><li id="ul0002-0007" num="0064"> TEXT ITEM—this tag describes a text label that is displayed </li><li id="ul0002-0008" num="0065"> CHECKBOX—this tag describes a checkbox </li><li id="ul0002-0009" num="0066"> HELP—this tag can define a help topic that is used by another element on the screen </li><li id="ul0002-0010" num="0067"> IMAGE—this tag describes an image that appears on those displays that support images </li><li id="ul0002-0011" num="0068"> ICON—this tag describes an icon </li><li id="ul0002-0012" num="0069"> EVENT—this defines an event to be processed by the virtual machine software. Events can be defined against the application as a whole, individual screens or individual items on a given screen. Sample events would be receipt of data over the wireless interface, or a edit of text in an edit box </li><li id="ul0002-0013" num="0070"> ACTION—this describes a particular action that might be associated with an event handler. Sample actions would be navigating to a new window or displaying a message box. </li></ul></li></ul>

0071The second category of example XML tags describes the network transaction section <b>50</b> of application definition <b>28</b>. These may include the following example XML tags: <ul id="ul0003" list-style="none"><li id="ul0003-0001" num="0000"><ul id="ul0004" list-style="none"><li id="ul0004-0001" num="0072"> TABLEUPDATE—using this tag, the application developer can define an update that is performed to a table in the device's local storage. Attributes allow the update to be performed against multiple rows in a given table at once; </li><li id="ul0004-0002" num="0073"> PACKAGEFIELD—this tag is used to define a field in a data package that passes over the wireless interface </li></ul></li></ul>

0074The third category of XML tags used to describe an application are those used to define a logical database that may be stored at the mobile device. The tags available that may be used in this section are: <ul id="ul0005" list-style="none"><li id="ul0005-0001" num="0000"><ul id="ul0006" list-style="none"><li id="ul0006-0001" num="0075"> TABLE—this tag, and its attributes, define a table. Contained within a pair of TABLE tags are definitions of the fields contained in that table. The attributes of a table control such standard relational database functions as the primary key for the table. </li><li id="ul0006-0002" num="0076"> FIELD—this tag describes a field and its attributes. Attributes of a field are those found in a standard relational database system, such as the data type, whether the field relates to one in a different table, the need to index the field, and so on. </li></ul></li></ul>

0077In addition to these XML tags, virtual machine software <b>24</b> may, from time to time, be required to perform certain administrative functions on behalf of a user. In order to do this, one of object classes <b>69</b> has its own repertoire of tags to intercommunicate with the middleware server <b>44</b>. Such tags differ from the previous three groupings in that they do not form part of an application definition file, but are solely used for administrative communications between the virtual machine software <b>24</b> and the middleware server <b>44</b>. Data packages using these tags are composed and sent due to user interactions with the virtual machine's configuration screens. The tags used for this include: <ul id="ul0007" list-style="none"><li id="ul0007-0001" num="0000"><ul id="ul0008" list-style="none"><li id="ul0008-0001" num="0078"> REG—this allows the application to register and deregister a user for use with the middleware server </li><li id="ul0008-0002" num="0079"> FINDAPPS—by using this operation, users can interrogate the server for the list of applications that are available to them </li><li id="ul0008-0003" num="0080"> APP REG—using this operation, the end-user can register (or deregister) for an application and have the application interface downloaded automatically to their device (or remove the interface description from the device's local storage). </li><li id="ul0008-0004" num="0081"> SETACTIVE—If the user's preferred device is malfunctioning, or out of power or coverage, they will need a mechanism to tell the Server to attempt delivery to a different device. The SETACTIVE command allows the user to set the device that they are currently using as their active one </li><li id="ul0008-0005" num="0082"> APPNOTIFY—this XML element is used by the middleware server <b>44</b> to communicate the fact that a new application or updated version of an existing application is available for downloading and use by the mobile device (i.e. a transaction definition file which facilitates use of the new or updated application is available for download from the middleware server <b>44</b>). As will be apparent, the APPNOTIFY tag is central to the new or updated application notification process. </li></ul></li></ul>

0083Referring again generally to the manner in which execution of server-based applications at mobile devices is facilitated, <figref idref="DRAWINGS">FIG. 5</figref> illustrates the organization of application definitions at middleware server <b>44</b> and how middleware server <b>44</b> may form an application definition file <b>28</b> (<figref idref="DRAWINGS">FIG. 4</figref>) for a given device <b>10</b>, <b>30</b>, <b>32</b> or <b>34</b>. In the illustration of <figref idref="DRAWINGS">FIG. 5</figref>, only two mobile devices <b>10</b> and <b>30</b> are considered. Typically, since network transactions and local data are the same across devices, the only piece of the application definition that varies for different devices is the user interface definition.

0084So, middleware server <b>44</b> stores a master definition <b>58</b> for a given server side application. This master definition <b>58</b> contains example user interface descriptions <b>48</b>, <b>54</b>, <b>56</b> for each possible type of mobile device <b>10</b>, <b>30</b>, <b>32</b>; descriptions of the network transactions <b>50</b> that are possible and data descriptions <b>52</b> of the data to be stored locally on the mobile device. Preferably, the network transactions <b>50</b> and data descriptions <b>52</b> will be the same for all mobile devices <b>10</b>, <b>30</b> and <b>32</b>.

0085For device <b>10</b>, middleware server <b>44</b> composes an application definition file <b>28</b> by querying the device type and adding an appropriate user interface description <b>48</b> for device <b>10</b> to the definitions for the network transactions <b>50</b> and the data <b>52</b>. For device <b>30</b>, middleware server <b>44</b> composes the application definition by adding the user interface description <b>54</b> for device <b>10</b> to the definitions for the network transactions <b>50</b> and data <b>52</b>.

0086The master definition <b>58</b> for a given application is created away from the middleware server and loaded onto the middleware server by administrative staff charged with its operation. Master definition files could be created either by use of a simple text editor, or by a graphical file generation tool. Such a tool might generate part or all of the file, using knowledge of the XML formatting rules, based on the user's interaction with screen painters, graphical data definition tools and the like. It will be appreciated that the master definition file <b>58</b> is an XML data instance which conforms to a predefined XML schema referenced above. Notably, when a new application or updated version of an existing application becomes available at the application server <b>70</b> (described in connection with <figref idref="DRAWINGS">FIG. 6</figref> below), a new master definition file <b>58</b> corresponding to the new or updated application will be created and stored at middleware server <b>44</b>.

0087<figref idref="DRAWINGS">FIG. 6</figref> illustrates the organization of middleware server <b>44</b> and associated master definitions <b>58</b>. Middleware server <b>44</b> may be any conventional application server, modified to function in manners exemplary of the present invention. As such, middleware server <b>44</b> includes a processor <b>60</b>, in communication with a network interface <b>66</b> and storage memory <b>64</b>. Middleware server <b>44</b> may be, for example, a Windows 2000 server, a Sun Solaris server, or the like. Memory of middleware server <b>44</b> stores an operating system such as Windows 2000, or Solaris operating system software <b>62</b>.

0088Network interface <b>66</b> enables middleware server <b>44</b> to transmit and receive data over a data network <b>63</b>. Transmissions are used to communicate with both the virtual machine software <b>24</b> (via the wireless networks <b>36</b>, <b>38</b> and wireless gateways <b>40</b>, <b>42</b>) and one or more application servers, such as application server <b>70</b>, that are the end recipients of data sent from the mobile client applications and the generators of data that is sent to the mobile client applications.

0089Memory at middleware server <b>44</b> further stores software <b>68</b>, exemplary of an embodiment of the present invention. Middleware server software <b>68</b>, when executed by middleware server <b>44</b> enables the middleware server to understand and compose XML data packages that are sent and received by the middleware server. These packages may be exchanged between middleware server <b>44</b> and the virtual machine software <b>24</b>, or between the middleware server <b>44</b> and the application server <b>70</b>. Middleware server software <b>68</b> may also provide a graphical user interface for use by a system administrator tasked with maintaining up-to-date access to applications hosted at application server <b>70</b> by users of mobile devices <b>10</b>, <b>30</b>, <b>32</b>, and <b>34</b>, or a subset thereof. Middleware server software <b>68</b> may be loaded from a machine readable medium.

0090As described above, communication between the application server <b>70</b> and the middleware server <b>44</b> can, in an exemplary embodiment, use HTTP running on top of a standard TCP/IP stack; however this is not a requirement. An HTTP connection between a running application at the application server <b>70</b> and the middleware server <b>44</b> is established in response to the application at a mobile device presenting the application. The server side application provides output to middleware server <b>44</b> over this connection. The server side application data is formatted into appropriate XML data packages understood by the virtual machine software <b>24</b> at a mobile device by the server side application.

0091That is, a server side application (or an interface portion of the application) formats application output into XML in a manner consistent with the format defined by the application definition file for the application. Alternatively, an interface component separate from the application could easily be formed with an understanding of the format and output for a particular application. That is, with a knowledge of the format of data provided and expected by an application at application server <b>70</b>, an interface component could be a produced using techniques readily understood by those of ordinary skill. The interface portion could translate application output to XML, as expected by middleware server <b>44</b>. Similarly, the interface portion may translate XML input from a mobile device into a format understood by the server side application.

0092The particular identity of the mobile device on which the application is to be presented may be identified by a suitable identifier, in the form of a header contained in the server side application output. This header may be used by middleware server <b>44</b> to forward the data to the appropriate mobile device. Alternatively, the identity of the connection could be used to forward the data to the appropriate mobile device.

0093<figref idref="DRAWINGS">FIG. 7</figref> illustrates a sequence diagram detailing data (application data or application definition files <b>28</b>) flow between mobile device <b>10</b> and middleware server <b>44</b>, in manners exemplary of an embodiment of the present invention.

0094For data requested from middleware server <b>44</b>, device <b>10</b>, under software control by virtual machine software <b>24</b> makes requests to middleware server <b>44</b> (also illustrated in <figref idref="DRAWINGS">FIG. 2</figref>), which passes over the wireless network <b>36</b> through network gateway <b>40</b>. Network gateway <b>40</b> passes the request to the middleware server <b>44</b>. Middleware server <b>44</b> responds by executing a database query on its database <b>46</b> that finds which applications are available to the user and the user's mobile device. For data passed from middleware server <b>44</b> to device <b>10</b>, data is routed through network gateway <b>40</b>. Network gateway <b>40</b> forwards the information to the user's mobile device over the wireless network <b>36</b>.

0095<figref idref="DRAWINGS">FIG. 7</figref> when considered with <figref idref="DRAWINGS">FIG. 3</figref> illustrates a sequence of communications between device <b>10</b>, and middleware server <b>44</b> that may occur when the user of a mobile device wishes to download an application definition file <b>28</b> for a server side application.

0096So, initially, device <b>10</b> interrogates server <b>44</b> to determine which applications are available for the particular mobile device being used. This may be accomplished by the user instructing the virtual machine software <b>24</b> at device <b>10</b> to interrogate the server <b>44</b>. Responsive to these instructions the virtual machine software <b>24</b> sends an XML message to the server requesting the list of applications (data flow <b>72</b>); as illustrated in <figref idref="DRAWINGS">FIG. 7</figref> the XML message may contain the <FINDAPPS> tag, signifying to the middleware server <b>44</b>, its desire for a list available application. In response, middleware server <b>44</b> makes a query to database <b>46</b>. Database <b>46</b>, responsive to this query, returns a list of applications that are available to the user and the mobile device. The list is typically based, at least in part, on the type of mobile device making the request, and the applications known to middleware server <b>44</b>. Middleware server <b>44</b> converts this list to an XML message and sends to the virtual machine (data flow <b>74</b>). Again, a suitable XML tag identifies the message as containing the list of available applications.

0097In response, a user at device <b>10</b> may choose to register for an available server side application. When a user chooses to register for an application, virtual machine software <b>24</b> at device <b>10</b> composes and sends an XML registration request for a selected application (data flow <b>76</b>) to middleware server <b>44</b>. As illustrated in <figref idref="DRAWINGS">FIG. 15</figref>, an XML message containing a <REG> tag is sent to middleware server <b>44</b>. The name of the application is specified in the message. The middleware server <b>44</b>, in response, queries its database for the user interface definition for the selected application for the user's mobile device. Thereafter, the middleware server creates the application definition file, as detailed with reference to <figref idref="DRAWINGS">FIG. 5</figref>. Then, middleware server <b>44</b> sends to the mobile device (data flow <b>78</b>-<figref idref="DRAWINGS">FIG. 7</figref>) the created application definition file <b>28</b>.

0098<figref idref="DRAWINGS">FIG. 8</figref> is a sequence diagram illustrating operation for notifying a mobile device of the availability of a new or updated application. In particular, the sequence diagram illustrates data flow between middleware server <b>44</b> and the virtual machine <b>24</b> executing at an exemplary mobile device.

0099For purposes of <figref idref="DRAWINGS">FIG. 8</figref>, it is assumed that a new application or updated version of an existing application has been made available at the application server <b>70</b> (<b>802</b>). It is also assumed that a new application definition file which corresponds to the new or updated application at application server <b>70</b> has been loaded or otherwise made available at the middleware server <b>44</b> (<b>804</b>).

0100In an exemplary embodiment, new or updated application notification is triggered by a system administrator at middleware server <b>44</b>. In particular, the system administrator, being aware of the new or updated application availability <b>802</b> and <b>804</b>, interacts with middleware server software <b>68</b> to cause a notification of the availability of the new or updated application to be sent to one or more mobile devices <b>10</b>.

0101An exemplary GUI <b>900</b> by which notification may be triggered is illustrated in <figref idref="DRAWINGS">FIG. 9</figref>. As illustrated, GUI <b>900</b> includes a list box <b>902</b> which contains a list of two groups mobile devices (“mobile groups”) with identifiers “Nexent” and “Nextair” of which the middleware server <b>44</b> is aware. mobile groups are sets of individual mobile devices which are grouped, e.g. by a system administrator, usually on the basis that the devices share similar application accessibility attributes. The grouping of mobile devices may be performed to ease system administration. For example, the mobile devices associated with employees of a particular department of a business enterprise may be incorporated into a single group (e.g. all mobile devices allocated to employees in a sales department are included in a “sales” group; all mobile devices allocated to marketing employees are included in a “marketing” group; and so on). Because employees of a particular department may all require access to the same set of applications, and because it may be desirable to ensure that employees are apprised of the latest applications, notification may be performed on the basis of mobile groups. Mobile groups may each have an associated maximum number of active mobile devices associated with the group.

0102Mobile groups may be used in conjunction with application groups defined at the middleware server <b>44</b> for purposes of defining the applications available to sets of mobile devices. Application groups are sets of applications to which access may be permitted or denied as a whole. Application groups may be defined, e.g. by a system administrator, to simplify application access control to applications on the middleware server <b>44</b> by sets of related mobile devices. For example, all sales-related applications may be grouped into a “sales” application group, to which each mobile device within a “sales” mobile group may be permitted access. The number of applications may differ between application groups. One application group may contain only a single application, while another may contain all of the applications present on the middleware server <b>44</b>.

0103Of course, it will be appreciated that the use of mobile groups and application groups for new or updated application notification purposes is not required. Notification may also be performed on a mobile device-by-mobile device basis or on an application-by-application basis.

0104Referring again to <figref idref="DRAWINGS">FIG. 9</figref>, using the checkboxes <b>904</b>, the system administrator may select which mobile devices are notified of the new or updated application. A check mark indicates notification is to be performed. In the illustrated example, the system administrator may also optionally enter a custom message that will be displayed to the mobile users along with the new application notification, which may help the user of the mobile device to better appreciate why the new or updated application should or should not be used.

0105When the Send Notification button <b>906</b> of the GUI <b>900</b> is depressed, the notification is sent to the virtual machine software <b>24</b>, which notification is illustrated by in <figref idref="DRAWINGS">FIG. 8</figref> at <b>806</b>.

0106For each mobile in each mobile group which is checked in list box <b>902</b>, a message will be queued, with the XML format <b>1000</b> illustrated in <figref idref="DRAWINGS">FIG. 10</figref>. As illustrated, the message includes an <APPNOTIFY> element (at lines <b>3</b> to <b>15</b>) having the following attributes: <ul id="ul0009" list-style="none"><li id="ul0009-0001" num="0000"><ul id="ul0010" list-style="none"><li id="ul0010-0001" num="0107"> ID—The application ID of the application in respect of which notification is being sent. In the case where a general application notify is sent (e.g. when an application group is activated for a mobile group), this has a predetermined value of “−<b>1</b>”. </li><li id="ul0010-0002" num="0108"> NAME—The application name of the application in respect of which notification is being sent </li><li id="ul0010-0003" num="0109"> DESC—A description of the application in respect of which notification is being sent </li><li id="ul0010-0004" num="0110"> VERSION—The version of the application in respect of which notification is being sent </li><li id="ul0010-0005" num="0111"> MSG—A custom message which may be entered by a system administrator triggering the notification. </li></ul></li></ul>

0112Also included in the message to a given mobile device will be a list of applications currently available to the mobile device, which is provided within the tags <APPS> . . . </APPS> illustrated in <figref idref="DRAWINGS">FIG. 10</figref> (at lines <b>6</b> to <b>14</b>). Each <APP> element represents a single application available to the relevant mobile device.

0113At the virtual machine software <b>24</b> operating at a mobile device, upon receiving notification <b>806</b> (<figref idref="DRAWINGS">FIG. 8</figref>), the custom message (or a predetermined standard message) is displayed to the user to notify them of the availability of the new or updated application, and the user is presented with the opportunity to register for (i.e. download) the application. When a user chooses to register for an application, virtual machine software <b>24</b> composes and sends an XML registration request for the selected application (data flow <b>808</b>, which is analogous to data flow <b>76</b> of <figref idref="DRAWINGS">FIG. 7</figref>) to middleware server <b>44</b>. The middleware server <b>44</b>, in response, queries its database for the user interface definition for the selected application for the user's mobile device. Thereafter, the middleware server creates the corresponding application definition file and sends it to the mobile device (data flow <b>810</b>, which is analogous to data flow <b>78</b> of <figref idref="DRAWINGS">FIG. 7</figref>).

0114Following the receipt of an application definition file for a new or updated application at a mobile device <b>10</b>, <b>30</b>, <b>32</b>, or <b>34</b>, parser <b>61</b> of virtual machine software <b>24</b> may parse the XML text of the newly received application definition file to form a tokenized version of the file. That is, each XML tag may be converted a defined token for compact storage, and to minimize repeated parsing of the XML text file. The tokenized version of the application definition file may be stored for immediate or later use by device <b>10</b>. In this context, the term “tokenized” may refer to placement of the XML structure into binary objects, which is much like conversion of a script into byte code.

0115Thereafter, assuming that the virtual machine software <b>24</b> of the mobile device is able to use the functionality defined by the interface definition file to send and receive data. Advantageously, the mobile device user now has access to the most recent version of the application.

0116<figref idref="DRAWINGS">FIG. 11</figref> illustrates the format <b>1100</b> of a general “application notify” message which may be sent whenever an application group is activated for a mobile group. This notification is similar to the notification illustrated in <figref idref="DRAWINGS">FIG. 10</figref>, except that the ID attribute is set to “−1” to indicate that a general notification is being provided and that the <APPNOTIFY> element lacks any other specified attributes.

0117It should be appreciated that new or updated application notification could be performed automatically in an alternative embodiment. That is, instead of being triggered by a system administrator at middleware server <b>44</b> as described above, application notification may occur automatically, e.g., whenever the middleware server <b>44</b> detects the loading of a new application definition file. Such automatic notification could be performed to all mobile devices (whether by mobile group or individually) or to a subset of mobile devices sharing a predetermined set of characteristics.

0118In the paragraphs which follow, the execution of a server-side application (whether a new/updated application or an existing application) by a mobile device in accordance with an application definition file is described.

0119Upon invocation of a particular application for which the device <b>10</b> has registered, the screen generation engine <b>67</b> of the virtual machine software <b>24</b> at the device causes the virtual device to locate the definition of an initial screen for that application. The initial screen is identified within the application definition file <b>28</b> for that application using a <SCREEN> tag, and an associated attribute of <First screen=“yes”>.

0120Steps performed by virtual machine software <b>24</b> in processing a first or subsequent screen are illustrated in <figref idref="DRAWINGS">FIG. 12</figref>. As illustrated, screen generation engine <b>67</b>, generates an instance of an object class, defining a screen by parsing the section of the XML application definition file corresponding to the <SCREEN> tag in step S<b>802</b>. Supported screen elements may be buttons, edit boxes, menus, list boxes, and choice items, as identified in Appendix “A”. Other screen elements, such as images and checkboxes, as detailed in Appendix “A” may also be supported. For clarity of illustration, their processing by screen generation engine <b>67</b> however, is not detailed. Each supported tag under the SCREEN definition section, in turn causes creation of instances of object classes within the virtual machine software <b>24</b>. Typically, instances of objects corresponding to the tags, used for creation of a screen, result in presentation of data at mobile device <b>10</b>. As well the creation of such objects may give rise to events (e.g. user interaction) and actions to be processed at device <b>10</b>.

0121Each element definition causes virtual machine software <b>24</b> to use the operating system of the mobile device to create corresponding display element of a graphical user interface as more particularly illustrated in <figref idref="DRAWINGS">FIG. 13</figref>. Specifically, for each element, the associated XML definition is read in step S<b>806</b>, S<b>816</b>, S<b>826</b>, S<b>836</b>, and S<b>846</b>, and a corresponding instance of a screen object defined as part of the virtual machine software <b>24</b> is created by the virtual machine software <b>24</b> in steps S<b>808</b>, S<b>818</b>, S<b>828</b>, S<b>838</b> and S<b>848</b>, in accordance with steps S<b>902</b> and onward illustrated in <figref idref="DRAWINGS">FIG. 13</figref>. Each interface object instance is created in step S<b>902</b>. Each instance takes as attribute values defined by the XML text associated with the element. A method of the virtual machine object is further called in step S<b>904</b>, and causes a corresponding device operating system object to be created. Those attributes defined in the XML text file, stored within the virtual machine object instance are applied to the corresponding instance of a display object created using the device operating system in steps S<b>908</b>S-S<b>914</b>. These steps are repeated for all attributes of the virtual machine object instance. For any element allowing user interaction, giving rise to an operating system event, the event handler <b>65</b> of virtual machine software <b>24</b> is registered to process operating system events, as detailed below.

0122Additionally, for each event (as identified by an <EVENT> tag) and action (as identified by an <ACTION> tag) associated with each XML element, virtual machine software <b>24</b> creates an instance of a corresponding event and action object forming part of virtual machine software <b>24</b>. Virtual machine software <b>24</b> further maintains a list identifying each instance of each event and action object, and an associated identifier of an event in steps S<b>916</b> to S<b>928</b>.

0123Steps S<b>902</b>-S<b>930</b> are repeated for each element of the screen in steps S<b>808</b>, S<b>818</b>, S<b>828</b>, S<b>838</b> and S<b>848</b> as illustrated in <figref idref="DRAWINGS">FIG. 12</figref>. All elements between the <SCREEN> definition tags are so processed. After the entire screen has been so created in memory, it is displayed in step S<b>854</b>, using conventional techniques.

0124As will be appreciated, objects are specific to the type of device executing the virtual machine software <b>24</b>. Functions initiated as a result of the XML description may require event handling. This event handling is processed by event handler <b>65</b> of virtual machine software <b>24</b> in accordance with the application definition file <b>28</b>. Similarly, receipt of data from a mobile network will give rise to events. Event handler <b>65</b>, associated with a particular application presented at the device similarly processes incoming messages for that particular application. In response to the events, virtual machine software <b>24</b> creates instance of software objects, and calls functions of those object instances, as required by the definitions contained within the XML definitions contained within the application definition file <b>28</b>, giving rise to the event.

0125As noted, the virtual machine software <b>24</b> includes object classes, allowing the virtual machine to create object instances corresponding to an <EVENT> tag. The event object classes includes methods specific to the mobile device that allow the device to process each of the defined XML descriptions contained within the application definition file, and also to process program/event flow resulting from the processing of each XML description.

0126Events may be handled by virtual machine software <b>24</b> as illustrated in <figref idref="DRAWINGS">FIG. 14</figref>. Specifically, as device handler <b>65</b> has been registered with the operating system for created objects, upon occurrence of an event, steps S<b>1002</b> and onward are performed in response to the operating system detecting an event.

0127An identifier of the event is passed to event handler <b>65</b> in step S<b>1002</b>. In steps S<b>1004</b>-S<b>1008</b>, this identifier is compared to the known list of events, created as a result of steps S<b>916</b>-S<b>930</b>. For an identified event, actions associated with that event are processed in step S<b>1008</b>-S<b>1014</b>.

0128That is, virtual machine software <b>24</b> performs the action defined as a result of the <ACTION> tag associated with the <EVENT> tag corresponding to the event giving rise to processing by the event handler <b>65</b>. The <ACTION> may cause creation of a new screen, as defined by a screen tag, a network transmission, a local storage, or the like.

0129New screens, in turn, are created by invocation of the screen generation engine <b>61</b>, as detailed in <figref idref="DRAWINGS">FIGS. 8 and 9</figref>. In this manner the navigation through the screens of the application is accomplished according to the definition embodied in the XML application definition.

0130Similarly, when the user wishes to communicate with the middleware server, or store data locally, event handler <b>65</b> creates instances of corresponding object classes within the object classes <b>69</b> of virtual machine software <b>24</b> and calls their methods to store or transmit the data using the local device operating system. The format of data is defined by the device local definition section <b>52</b>; the format of network packages is defined in the network transaction package definition section <b>50</b>.

0131For example, data that is to be sent to the wireless network is assembled into the correct XML packages using methods within an XML builder object, formed as a result of creating an instance of a corresponding object class within object classes <b>69</b> of virtual machine software <b>24</b>. Methods of the XML builder object create a full XML package before passing the completed XML package to another message server object. The message server object uses the device's network APIs to transmits the assembled data package across the wireless network.

0132Received XML data packages from network <b>63</b> (<figref idref="DRAWINGS">FIG. 2</figref>) give rise to events processed by event handler <b>65</b>. Processing of the receipt of data packages is not specifically illustrated in <figref idref="DRAWINGS">FIG. 13</figref>. However, the receipt of data triggers a “data” event of the mobile device's operating system. This data event is passed to the virtual machine, and event handler <b>65</b> inspects the package received. As long as the data received is a valid XML data package as contained within the application definition, the virtual machine inspects the list of recognised XML entities.

0133So, for example, a user could send a login request <b>80</b> by interacting with an initial login screen, defined in the application definition file for the application. This would be passed by the middleware server <b>44</b> to the backend application server <b>70</b>. The backend application server according to the logic embedded within its application, would return a response, which the middleware server <b>44</b> would pass to the virtual machine software <b>24</b>. Other applications, running on the same or other application servers might involve different interactions, the nature of such interactions being based upon the functionality and logic embedded within the application server <b>70</b>.

0134<figref idref="DRAWINGS">FIG. 16</figref> illustrates sample XML messages passed as the result of message flows illustrated in <figref idref="DRAWINGS">FIG. 6</figref>. For each message, the header portion, between the <HEAD> . . . </HEAD> tags contains a timestamp and the identifier of the sending device.

0135Example message <b>72</b> is sent by the mobile device to request the list of applications that the server has available to that user on that device. It specifies the type of device by a text ID contained between the <PLATFORM> . . . </PLATFORM> tags. Example message <b>74</b> is sent in response to message <b>70</b> by middleware server <b>44</b> to the mobile device <b>10</b>. It contains a set of <APP> . . . </APP> tag pairs, each of which identifying a single application that is available to the user at device <b>10</b>. Example message <b>76</b> is sent from the mobile device <b>10</b> to middleware server <b>44</b> to register for a single server side application. The tags specify information about the user. Message <b>78</b> is sent by the middleware server <b>44</b> to the mobile device in response to a request to register device <b>10</b> for an application. The pair of tags <VALUE> . . . </VALUE> gives a code indicating success or failure. In the sample message shown, a success is shown, and is followed by the interface description for the application, contained between the <INTERFACE> . . . </INTERFACE> tags. This interface description may then be stored locally within memory <b>16</b> of device <b>10</b>.

0136As noted, when a user starts an application that has been downloaded in the manner described above, the virtual machine software <b>24</b> reads the interface description that was downloaded for that device <b>10</b>, and the virtual machine software <b>24</b> identifies the screen that should be displayed on startup, and displays its elements as detailed in relation to <figref idref="DRAWINGS">FIGS. 9 and 10</figref>. The user may then use the functionality defined by the user interface definition section <b>48</b> of the application definition <b>28</b> to send and receive data from a server side application.

0137For the purposes of illustration, <figref idref="DRAWINGS">FIGS. 16 and 17</figref> illustrate the presentation of a user interface for a sample screen on a Windows CE Portable Digital Assistant. As illustrated in <figref idref="DRAWINGS">FIG. 17</figref>, a portion of an application definition file <b>28</b> defines a screen with the name ‘New Msg’. This interface description may be contained within the user interface definition section <b>48</b> of an application definition file <b>28</b> associated with the application. The screen has a single button identified by the <‘BTN NAME’=“OK”, CAPTION=“Send” INDEX=“0”> tag, and identified as item D in <figref idref="DRAWINGS">FIG. 17</figref>. This button (if selected at run time) gives rise to a single event, (identified by the <EVENTS NUM=“1” tag) giving rise to a single associated action (defined by the tag <ACTION TYPE=“ARML”>). This action results in the generation of a network package (defined by the tag <PKG TYPE=“ME”>), having an associated data format as defined between the corresponding tags. Additionally, the screen has three editboxes, as defined after the <EDITBOXESNUM=3> tag, and identified as items A, B, and C.

0138Upon invocation of the application at the local device, screen generation engine <b>67</b> of virtual machine software <b>24</b> at the device process the screen definition, as detailed with reference to <figref idref="DRAWINGS">FIGS. 8 and 9</figref>. That is, for each tag D, the screen generation engine <b>67</b> creates a button object instance, in accordance with steps S<b>804</b>-S<b>812</b>. Similarly for each tag A, B and C within the application definition file, virtual machine software <b>24</b> at the device creates an instance an of edit box object (i.e. steps S<b>834</b>-S<b>842</b> (<figref idref="DRAWINGS">FIGS. 8 and 9</figref>)). The data contained within the object instances reflects the attributes of the relevant button and edit box tags, contained in the application definition <b>28</b> for the application.

0139The resulting screen at the mobile device is illustrated in <figref idref="DRAWINGS">FIG. 16</figref>. Each of the screen items is identified with reference to the XML segment within XML portion <b>92</b> giving rise to the screen element. The user interface depicts a screen called ‘NewMsg’, which uses the interface items detailed in <figref idref="DRAWINGS">FIG. 12</figref>, but which adds the ability to compose and send data. This screen has three edit boxes, named ‘To’, ‘Subject’ and ‘Body’ as displayed in <figref idref="DRAWINGS">FIG. 16</figref> (<b>84</b>,<b>86</b>,<b>88</b>); these are represented by the XML tags A, B and C. The screen also incorporates a button, named ‘OK’, also as displayed in <figref idref="DRAWINGS">FIG. 16</figref> (<b>90</b>), which represents the XML BTN element (tag D of <figref idref="DRAWINGS">FIG. 17</figref>).

0140Call-backs associated with the presented button cause graphical user interface application software/operating system at the mobile device to return control to the event handler <b>65</b> of virtual machine software <b>24</b> at the device. Thus, as the user interacts with the application, the user may input data within the presented screen using the mobile device API. Once data is to be exchanged with middleware server <b>44</b>, the user may press the OK button, thereby generating an event, initially handled by the operating system of the mobile device. However, during the creation of button D, in steps S<b>804</b>-S<b>810</b> any call-back associated with the button was registered to be handled by event handler <b>65</b> of virtual machine software <b>24</b>. Upon completion, virtual machine software <b>24</b> receives data corresponding to the user's interaction with the presented user interface and packages this data into XML messages using corresponding objects, populated according to the rules within the application definition file.

0141Event handler <b>65</b>, in turn processes the event caused by interaction of the button in accordance with the <EVENT> tag and corresponding <ACTION> tag associated with the button D. The events, and associated actions are listed as data items associated with the relevant user interface item, as result of the EVENT and ACTION tags existing within the definitions of the relevant user interface item, within the application definition file. This <ACTION> tag causes the virtual machine software <b>24</b> to create an instance of an object that sends an XML package to the middleware server in accordance with the format defined between the <ACTION> tag. That is, a “template” (defined after the <PKG TYPE=“ME”> tag) for the XML package to be sent is defined against the EVENT handler for a given user interface item. This template specifies the format of the package to be sent, but will include certain variable fields. These are pieces of data in the formatted XML package that will vary according to the values contained in data entry fields on the current and previous screens. The definition of the template specifies which data entry field should be interrogated to populate a given entry within a data package that is to be sent.

0142This template fills some of its fields dynamically from data inserted by a user into edit boxes that were presented on the mobile device's screen. The template has within it certain placeholders delimited by square brackets. These placeholders specify a data source from which that section of the template should be filled. A data source might be a user interface field on the current screen, a user interface field on the previous screen, or a database table. Virtual machine software <b>24</b>, reading the data source name, searches for the field corresponding to that data source and replaces the placeholder with actual data contained within the data source. For example, the SUBJECT attribute of the MAIL tag in XML portion <b>92</b> is read from the edit box named ‘Subject’ on the screen named ‘NewMsg’ This process is repeated for each such placeholder, until the virtual machine, reading through the template has replaced all placeholders in the template. At this point the template has been converted into a well-formed XML message <b>94</b>.

0143A resulting XML message <b>94</b> containing data formed as a result of input provided to the fields of the “NewMsg” screen is illustrated in <figref idref="DRAWINGS">FIG. 18</figref>. This exemplary XML message <b>94</b> that is created by pressing the button <b>90</b> in XML message portion <b>92</b>. In this case, the editbox <b>86</b> named ‘Subject’ contains the text “Hello Back”; the editbox <b>84</b> named ‘To’ contains the text “jdoe@mycompany.com”; and the editbox <b>88</b> named ‘Body’ contains the text “I am responding to your message”.

0144The virtual machine software <b>24</b> using the template inspects these three fields, and places the text contained within each edit box in the appropriate position in the template. For example, the placeholder [Subject] is replaced by “Hello Back”. The virtual machine software <b>24</b>, inspecting the template contained in the XML message portion <b>92</b> and populating the variable fields, creates the sample XML message <b>94</b> by invoking the functionality embedded within an XML builder software object. Once the XML message <b>94</b> has been assembled in this fashion, the relevant method of the message server object is then invoked to transmit the XML message <b>94</b> in a data package across the network.

0145Similarly, when data is received, the event handler <b>65</b> of the virtual machine software <b>24</b> is notified. In response, the event handler examines the data package that it has received using the parser <b>61</b> to build a list of name value pairs containing the data received. Thereafter, methods within an object class for processing incoming packets are invoked to allow virtual machine software <b>24</b> to inspect the application definition for the application to identify the fields in the database and user interface screens that need to be updated with the new data. Where screens are updated, this is done according to the procedures normal to that device.

0146Handling of incoming packages is defined in the application definition file <b>28</b> at the time the application description file was downloaded. That is, for each of the possible packages that can be received, application description file <b>28</b> includes definitions of database tables and screen items that should be updated, as well as which section of the package updates which database or screen field. When a package is received, event handler <b>65</b> of virtual machine software <b>24</b> uses rules based on the application description file <b>28</b> to identify which database and screen fields need to be updated.

0147<figref idref="DRAWINGS">FIGS. 19A-19C</figref> similarly illustrates how local storage on the device, and the messages that update it, are defined in the application definition file <b>28</b>. XML portion <b>96</b> forming part of the device local definition section <b>52</b> of an application definition defines an example format of local storage for the email application described in <figref idref="DRAWINGS">FIGS. 12 and 13</figref>. Two example tables, labeled E and F are defined in the local storage for the application. One table (E) stores details of sent emails. A second table (F) stores the recipients of sent emails. The first table E, “SentItems”, has four fields; the second table F, “Recipients” has three fields. This is illustrated in graphical form below the XML fragment.

0148<figref idref="DRAWINGS">FIGS. 19A and 19B</figref> further illustrates the use of local storage to store to data packages that are sent and received. Specifically, as illustrated in <figref idref="DRAWINGS">FIG. 19A</figref> the table given in <figref idref="DRAWINGS">FIG. 19A</figref> may store an email contained in the example message <b>94</b>, shown in <figref idref="DRAWINGS">FIG. 18</figref>. So application definition file <b>28</b> for this application would contain, along with XML message portions <b>92</b> and XML portion <b>96</b>, the XML fragment <b>102</b>. XML fragment <b>102</b> defines how the data packages composed by the XML message portion <b>92</b> (an example of which was illustrated in <figref idref="DRAWINGS">FIG. 17</figref>), updates the tables defined by the XML portion <b>96</b>.

0149XML fragment <b>102</b> includes two sections <b>104</b> and <b>106</b>. First section <b>104</b> defines how the fields of the data package would update the “SentItems” table E. An example line <b>108</b> describes how the ‘MSGID’ field in the data package would update the ‘LNGMESSAGEID’ field in the table E. Similarly, the second section <b>106</b> describes how the fields of the data package would update the “Recipients” table.

0150Attributes of the illustrated <AXDATAPACKET> tag instruct the virtual machine software <b>24</b> as to whether a given data package should update tables in local storage. These rules are applied whenever that package is sent or received.

0151As can be seen from the preceding description and example, such an approach has significant advantages over the traditional method of deploying applications onto mobile devices. First, the definition of an application's functionality is separated from the details associated with implementing such functionality, allowing the implementers of a mobile application to concentrate on the functionality and ignore implementation details. Second, application definitions can be downloaded wirelessly, wherever the device happens to be at the time. This greatly improves the usefulness of the mobile device, by removing reliance on returning the device to a cradle and running a complex installation program. Thirdly, the use of application definition files allows flexible definitions for numerous applications. Server-side application may be easily ported for a number of devices.

0152It will be further understood that the invention is not limited to the embodiments described herein which are merely illustrative of a preferred embodiment of carrying out the invention, and which is susceptible to modification of form, arrangement of parts, steps, details and order of operation. The invention, rather, is intended to encompass all such modification within its scope, as defined by the claims.