Abstract:
Disclosed is a method for remotely controlling a first computing device from at least one of a plurality of second computing devices, the first computing device having a user interface and a data communications connection to the second computing device and the second computing device adapted to present a user interface. The method comprises analyzing the static and dynamic logic of the first computing device&#39;s user interface and creating a logically equivalent user interface in a platform-independent format for the second computing device. The equivalent user interface enables control of the first coupling device from the second computing device.

Description:
This invention relates to the field of remotely controlling a first computing device from at least one of a plurality of second computing devices. This application corresponds to U.S. provisional patent application Ser. No. 60/194,168 filed Apr. 3, 2000. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     A remote control system enables a first (or “local”) computing device to be controlled via a second (or “remote”) computing device. 
     U.S. Pat. No. 5,949,412 issued to Huntsman, entitled “Computer Remote Control System”, proposed a remote control system where the client is a Web browser. A screen image of the controlled application is transferred as a bitmap image displayable within a Web browser (GIF file). 
     His solution lacks the following: 
     client graphical user interface (GUI) is a bitmap image and not made of logical elements; 
     no on-the-fly conversion; 
     no continuous update of client screen; 
     no customization and adaptation of the client widgets; 
     his invention used a click-able image to send coordinates to the server, however, he does not explain how the image is constructed nor does he claim that the image is constructed automatically; 
     while mouse input is supported, keyboard input is not, though keyboard capabilities are mentioned in passing; 
     the client uses HTML, not DHTML, consequently, there are no event handlers (only coordinate click events); 
     no collaboration; 
     no support for 3-tier architecture (our FIG.  1 ). 
     Other prior art remote control systems had similar limitations and further limitations: 
     First, they generally involve a bit-to-bit representation of the first computing device&#39;s GUI on the second computing device. This is an inefficient method which does not lend itself to customization: the GUI on the second computing device has to be the same as that on the first computing device. 
     Second, the communications are binary, which is heavier than logical, text based communications. For example, if the first GUI changes to show new text, the image of that text must be sent to the second computing device. Whereas if the communication were logical, simply the text would be passed. 
     Third, since the second GUI is just a graphic, all its logic must come from the first computing device. For example, if the remote user clicks on a button, that event must be sent to the first computing device which then sends back an image of the button being recessed. Whereas if the second computing device had display level logic, it would know to display the clicking without having to contact the first computing device. 
     Fourth, binary communications are not “firewall friendly”. Generally a firewall must be reconfigured to allow a remote control system to operate across it. 
     Fifth, since the binary communications format of prior remote control applications is less secure, when a first computing device is on a LAN, it must be on the gateway to the LAN. In other words, the first computing device cannot be a workstation on the LAN because that might compromise security. 
     Sixth, until now it has not been possible to separate the GUI logic of desktop applications from the program logic as it is with client-server applications. 
     Seventh, because the previous remote control systems used “bit-to-bit” communications, there were sometimes problems getting the system to work correctly when the second computing device was a different software and/or hardware platform than the first computing device. 
     The present invention differs substantially from prior solutions in that the user interface (UI) of the first computing device is analysed and a second, logically equivalent, UI is generated and sent to the second computing device. A user can thereby operate the first computing device via the second UI on the second computing device. In a preferred embodiments of the present invention the UI is specifically a GUI (graphical user interface). The logically equivalent GUI is constructed, in these embodiments, of DHTML which is displayed in a browser on the second (remote) computing device. 
     To illustrate how the logical GUI used in the present invention differs from the image-based systems used in prior remote control systems, consider the example of Microsoft Corporation&#39;s Windows (R). There the GUI consists of objects, such as buttons. When the user clicks a button, the button display changes to show itself appearing to be recessed and then return to its original state. At the same time the button might send a “clicked-on” message to the underlying program. The underlying program might then reply by changing the text or color of the button. 
     In some operating systems the GUI&#39;s structure can be detected and analyzed (e.g., via the Windows HWND handle). Based on this analysis, the second, logically equivalent UI mentioned above can be built. The second UI becomes the new interface to the first computing device— In effect, the present invention converts a desktop application into a two tier application (client-server). 
     The second UI is as platform-independent as possible so as to enable it to be displayed on a wide range of second computing devices. For example, the second GUI can be built with a dynamic markup language such as DHTML, which can be viewed in most Web browsers, irrespective of the platform the browser is running on. 
     Therefore, one of the major objects of the present invention is to analyze a program&#39;s UI and build a functional universal copy by which a remote computing device can control the original program. 
     Another object of the present invention is to effect this process on-the-fly, i.e., when a user of the second computing device opens a new program on the local computing device for remote control, the present invention automatically analyzes the first GUI, generates the second GUI, and sends it to the second computing device. No user intervention is required. 
     To summarize some of the major innovations of the present invention: it detects (on the fly) the appearance and logic of the UI of a local program (application or operation system) on a first computing device, transfers control of the local program to the logical UI running on the second computing device, and enables post-processing customization of the logical UI, its interaction with the user, and its interaction with the local program. And these operations can be performed on local programs that were not designed for client-server operation. 
     Some of the major advantages of the present invention are as follows: 
     First, a first GUI is converted to a second, logically equivalent GUI— not a bit-to-bit image. This conversion is done on-the-fly: as a layout (window) is displayed in the first GUI, a logically equivalent duplicate GUI is generated and transferred to the second computing device where it is displayed. 
     Second, less data needs to be transferred since only logic is transferred, not pixel changes. For example, if the local program changes the text on a GUI object, the remote client is sent just an instruction to change the test displayed rather than a completely new image of the object including the new text. 
     Third, the remote client can display results of user input itself. For example, when a user clicks a button, the DHTML page handles displaying the visual effect without having to be sent an image of the button going in and then another image of the button coming back out. 
     Fourth, since the remote GUI is separate from the local program, the second GUI can be customized (after the on-the-fly creation) in various respects, including: the appearance/location of GUI objects, the handling of user actions, and/or the handling of events (messages) from the local application. 
     Fifth, the DHTML is sent to the remote client as test via the HTTP protocol. This is a well known, secure protocol that conforms to security requirements. For example, firewalls normally enable HTTP data communications. Therefore in LAN installations, the first computing device is not restricted for security reasons to a gateway, and instead can be any workstation on the LAN. 
     Sixth, the remote GUI will display correctly in any second computing device capable of displaying a DHTML web page, regardless of whether that second computing device is a different type of hardware, (e.g., mobile phone, personal digital assistant, etc.) and/or has a different resolution than the first computing device. 
     Seventh, when a second computing device joins an active remote control session it receives the second GUI in its current state. 
     Eighth, remote GUIs for multiple local programs can be combined in a single remote GUI. 
     Ninth, multiple instances of a remote GUI for a given local program can run simultaneously on multiple remote computing devices, enabling active or passive collaboration. 
     Tenth, the second GUI can be frozen at any time—when unfrozen it will update to display the current state of the local program. 
     BRIEF DESCRIPTION OF THE PRESENT INVENTION 
     There is thus provided in accordance with a preferred embodiment of a method for remotely controlling a first computing device from at least one of a plurality of second computing devices, the first computing device having a user interface and a data communications connection to to the second computing device, the second computing device adapted to present a user interface, the method comprising: 
     analyzing the static and dynamic logic of the first computing device&#39;s user interface; 
     creating an equivalent user interface in a platform-independent format, wherein said static and dynamic logic is substantially replicated; 
     sending said equivalent user interface to the second computing device where it is implemented; 
     handling user input to said equivalent user interface, including sending output to the first computing device; 
     handling output originating in the first computing device, said handling including sending output to said equivalent user interface on the second computing device; 
     thereby enabling control of the first computing device from the second computing device. 
     Furthermore, in accordance with another preferred embodiment there is provided: 
     A method for remotely controlling a first computing device from at least one of a plurality of second computing devices, the first computing device having a graphical user interface and a data communications connection via a Web server to the second computing device, the second computing device adapted to display a Web browser, the method comprising: 
     analyzing the static and dynamic logic of the first computing device&#39;s graphical user interface and creating an equivalent graphical user interface in a Web browser supported format, wherein said static and dynamic logic is substantially replicated; 
     sending said equivalent graphical user interface to the second computing device where it is displayed in the Web browser; 
     detecting changes in the status of the first computing device and sending those changes to said equivalent graphical user interface; 
     receiving control input from said equivalent graphical user interface and executing it on the first computing device; 
     thereby enabling control of the first computing device from the second computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said equivalent graphical user interface is created in real time. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said equivalent graphical user interface is created automatically. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said equivalent graphical user interface&#39;s visual characteristics, its input handlers, and its output handlers is customizable. 
     Furthermore, in accordance with another preferred embodiment of the present invention, the most recent state of the first computing device is continuously sent to said equivalent graphical user interface in response to polling from said equivalent graphical user interface. 
     Furthermore, in accordance with another preferred embodiment of the present invention, the most recent state of the first computing device is sent to any additional computing device that joins the remote control session. 
     Furthermore, in accordance with another preferred embodiment of the present invention, the state of said equivalent graphical user interface can be frozen at any time and when unfrozen is immediately update to the current state of the first computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, a software component on the first computing device performs said analysis of the first computing device&#39;s graphical user interface. 
     Furthermore, in accordance with another preferred embodiment of the present invention, a software component on the first computing device monitors output events from the first computing device and based on said dynamic and static analysis, determines what action to take. 
     Furthermore, in accordance with another preferred embodiment of the present invention, a software component on the first computing device monitors input events from the second computing device and handles those events based on said dynamic and static analysis. 
     Furthermore, in accordance with another preferred embodiment of the present invention, a software component on said Web server mediates communication between the first computing device and the said equivalent graphical user interface. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said Web server is on the first computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said Web server is on a separate hardware device and has data communication connections with the first computing device and with the second computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said data communications connection between said Web server and the first computing device is a LAN. 
     Furthermore, in accordance with another preferred embodiment of the present invention, there if provided: 
     A system for remotely controlling a first computing device from at least one of a plurality of second computing devices, the first computing device having a graphical user interface and a data communications connection via a Web server to the second computing device, the second computing device adapted to display a Web browser, the system comprising: 
     a window analysis system that analyzes the static and dynamic logic of the first computing device&#39;s graphical user interface and creates an equivalent graphical user interface in a Web browser supported format, wherein said static and dynamic logic is substantially replicated; 
     a mediation system that: 
     sends said equivalent graphical user interface to the second computing device where it is displayed in the Web browser, and sends updated information about the state of the first computing device to the equivalent graphical user interface, and receives control input from the equivalent graphical user interface; 
     a visual status monitoring system that detects changes in the status of the first computing device and sends those changes to said mediation system for transfer to the second computing device; 
     a command executing system that receives said control input from said mediation system and executes it on the first computing device; 
     thereby enabling control of the first computing device from the second computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said equivalent graphical user interface is created in real time. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said equivalent graphical user interface&#39;s visual characteristics, its input handlers, and its output handlers can be customized. 
     Furthermore, in accordance with another preferred embodiment of the present invention, the most recent state of the first computing device is continuously sent to said equivalent graphical user interface in response to polling from said equivalent graphical user interface. 
     Furthermore, in accordance with another preferred embodiment of the present invention, the state of said equivalent graphical user interface can be frozen at any time and when unfrozen is immediately updated to the current state of the first computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said mediation system sends an updated equivalent graphical user interface to any additional computing device that joins the remote control session. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said Web server is on the first computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said Web server is on a separate hardware device and has data communication connections with the first computing device and with the second computing device. 
     Furthermore, in accordance with another preferred embodiment of the present invention, said data communications connection between said Web server and the first computing device is a LAN. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIG. 1 is a high level architectural view in accordance with the principles of the present invention. 
     FIG. 2 is a high level architectural view in accordance with the principles of the present invention. 
     FIG. 3 is a sample dialog box layout and the code generated for that layout in accordance with the principles of the present invention. 
     FIG. 4 is an architectural view of the primary components of the local server component in accordance with the principles of the present invention. 
     FIG. 5 is a flow chart of the process for handling events received from the second computing device in accordance with the principles of the present invention. 
     FIG. 6 is a flow chart of the process for handling events occurring on the first computing device in accordance with the principles of the present invention. 
     FIG. 7 is an architectural view of the mediating software component in accordance with the principles of the present invention. 
    
    
     DETAILED DESCRIPTION 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 Glossary 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 (G)UI 
                 (Graphical) User Interface 
               
               
                 Client 
                 Standard Internet browser capable apparatus 
               
               
                 machine 
               
               
                 Collaboration 
                 Operation mode where many remote clients are 
               
               
                   
                 working on the same instance of the same application. 
               
               
                 DCE-RPC 
                 Data Communications Exchange - Remote Procedure 
               
               
                   
                 Call 
               
               
                 DCOM 
                 Dynamic Component Object Model (Microsoft 
               
               
                   
                 Technology) 
               
               
                 DHTML 
                 Dynamic Hypertext Markup Language 
               
               
                 HTTP 
                 Hypertext Transfer Protocol 
               
               
                 HWND 
                 Window handle in Windows environment 
               
               
                 IPC 
                 Internal Procedure Call 
               
               
                 ISDN 
                 Integrated Services Digital Network 
               
               
                 Layout 
                 Set of widgets in predetermined geographic 
               
               
                   
                 configuration onscreen. An example in Microsoft 
               
               
                   
                 Corporation&#39;s Windows is an application window or 
               
               
                   
                 dialog box. A layout is represented on a Web browser 
               
               
                   
                 as an DHTML page. 
               
               
                 WAP 
                 Wireless Application Protocol 
               
               
                 Widget 
                 A graphical onscreen object. A widget may serve as a 
               
               
                   
                 means to input commands or data to a computer 
               
               
                   
                 program and/or to display data from a computer 
               
               
                   
                 program. 
               
               
                 WML 
                 Wireless Markup Language 
               
               
                 XML 
                 eXtended Markup Language 
               
               
                   
               
             
          
         
       
     
     The present invention provides a method and a system for remote control of a first (or “local”) computing device by at least one of a plurality of second (or “remote”) computing devices. 
     This invention analyzes the first computing device&#39;s user interface on-the-fly, creates a logically equivalent second user interface in a universal (i.e., platform-independent) format, and sends it to the second computing device. 
     The second user interface running on the second computing device (“remote interface”) communicates with the first computing device (“local program”) via two software intermediaries, which are the primary components of the present invention. These intermediaries are shown in FIG.  1  and FIG. 2 They are the local server  18  software program, and mediator  16  software program. 
     The local server  18  comprises three active software components: window analyzer  34 , command executor  32 , and visual status monitor  30 . The local server  18  stores data in a configuration database  36 . 
     The local server  18  does the following: it monitors the UI output from the local program and sends appropriate output to the remote computing device  10  via the mediator  16 ; it sends commands received from the second computing device  10  via the mediator  16  to the local program; it analyzes the layouts (windows) displayed by the local program and then creates and maintains the logically equivalent GUI on the second computing device  10 . 
     The other major component of the present invention, the mediator software program  16 , serves as a mediator between the local server  18  and the second computing device  10 . The mediator receives input from both entities and sends output to both entities. In addition, it is the mediator that makes it possible to carry out collaborative sessions where multiple second computing devices  10  share a single local program. 
     The current invention is described here in two preferred embodiments wherein the local program runs in a Microsoft Windows GUI environment on a first computing device connected via the Internet to at least one of a plurality of second computing devices and wherein the second user interface is implemented as a DHTML web page displayed in a Web browser. However, it will be apparent to one skilled in the art that the present invention can be embodied alternatively using other types of user interface, operating system, communications connections, and/or remote interface implementation. The second computing device  10  in these embodiments may be any device with standard Internet browsing capabilities, such as a desktop PC handheld device, personal digital assistant, smart phone, network computer, etc. 
     In one preferred embodiment, shown in FIG. 1, second computing devices  10  are connected via the Internet  12  and firewall  14  to a mediator software program  16  residing on a Web server  15  connected to a LAN and communicate via HTTP (or other Internet secure protocol). The mediator program  16  communicates with a local server software program  18  residing on a first computing device  17  on the LAN via an intranet protocol (e.g., DCOM or DCE-RPC). 
     Another preferred embodiment is shown in FIG.  2 . Second computing devices  10  are connected via the Internet  12  and firewall  14  to a mediator  16  software program residing on a Web server  15  and communicate via HTTP (or other Internet secure protocol). In this embodiment the mediator  16  and the local server  18  reside on the same first computing device  17  (which is also a Web server  15 ), and communicate via an inter-process protocol (e.g., COM or IPC). 
     The description which follows applies for both of the preferred embodiments of the present invention. The description shows how the mediator  16  and the local server  18  work together to enable a second computing device  10  to control a local program (i.e., application, operating system component, etc.) running on the same first computing device  17  as the local server  18 . The relationship between the second computing device  10  and the local program it controls can be one to one, one to many, or many to one. In other words, one or more second computing devices can control one or more local programs running on one or more first computing devices. 
     The interface between the remote interface and the local program can be modified with post-processing. For example, new objects can be added to the remote interface, the behaviors of remote interface objects can be changed, etc. 
     The remote control system is activated when a user of a second computing device  10  contacts the mediator  16 . In these embodiments this is done by entering a URL in a browser on the second computing device  10  (can optionally be password protected. The mediator  16  replies with a list of local servers  18  and the user can select one or more programs on one or more local servers. 
     As will described later, the mediator sends the second computing device  10  a set of DHTML or WML pages, which run on the second computing device&#39;s  10  Web browser. These pages form the second user interface by which a user can control the first computing device  17 . 
     FIG. 3 shows a sample layout  40  (dialog box) for the second user interface and the layout&#39;s DHTML code. The term layout is used here to refer to a primary GUI entity, for example an application window or dialog box. On each page part of the script constantly polls the mediator  16  to query for changes that affect the visible state of any widget in the layout (or potentially affect the visible state, e.g., when a menu item is added and will be visible the next time the menu is opened). 
     When a user of the second computing device  10  performs an action (mouse or keyboard input) on a widget, the widget has associated event handling code. If the event handling code calls for it, an event or events are passed to the mediator  16 , from which it/they are passed to the local server for execution. 
     Multiple second computing devices  10  running on different machines can connect to the same mediator  16  to view the same application session simultaneously. Control can be allotted to one or more of these concurrent users. In an alternative configuration, each client has its own mediator  16  and runs its own session. 
     A second computing device  10  may freeze its input data stream (independent of other clients collaborating on the same application). When the client unfreezes, it is updated immediately with the current sate of the application (which is always maintained in the mediator  10 ). 
     FIG. 4 shows the primary components of the local server  18 , which runs on the first computing device. When a program is first selected by a remote user, the local server  18  activates the program (if it is not already active) and the window analyzer  34  generates a DHTML page for each layout. 
     The DHTML page can be customized for properties such as window size, font, language, color, refresh rate, target device, and communication protocol (e.g. HTTP, HTTP, WAP). 
     The window analyzer  34  can generate the DHTML pages according to parameters such as target second computing device  10  (e.g., Palm-Pilot, Cell-Phone), communication type (e.g., modem ISDN), or target browser (e.g., Microsoft Corporation&#39;s Explorer, Netscape Corporation&#39;s Navigator). 
     The visual status monitor  30  monitors GUI events (e.g., Windows messages) generated by the local program and updates the widgets (DHTML page) running on the second computing device  10 . 
     The command executor  32  gets messages from the widgets on the second computing device  10  and translates them into commands (or a series of commands) executed on the local program. 
     FIG. 3 shows a sample layout  40  (dialog box) and the layout&#39;s DHTML code  42  generated by the window analyzer. When the DHTML is displayed in the browser of the second computing device  10 , it substantially replicates the GUI of the local program. 
     The window analyzer  34  takes the GUI object identifier (e.g., HWND in the Windows environment) as input and analyzes the construction of the GUI object and its child GUI objects. The analysis is logical, i.e., the window analyzer  34  identifies the UI object type (button, list, etc.) and creates a database  36  record consisting of three parts: the object&#39;s static attributes (e.g., size, visibility state, etc.), the object&#39;s interface to the local program, and the object&#39;s interface to the second computing device  10 . 
     The DHTML code that the window analyzer  34  creates for a widget consists of the static attributes to display, handlers for events received from the local programs, and handlers for events occurring on the second computing device  10  (e.g., keyboard, mouse click, etc.). 
     When the DHTML page is running in the browser of the second computing device  10  and an event occurs (e.g., mouse click on a widget), then, depending on the widget and its handler for that event, one of the following occurs: the event generates output to the command executor  32 , the event affects the widget in the browser, both, or nothing. 
     The window analyzer  34  also records in the database  36  the local server input event handlers for output generated by the DHTML widget. The input event handlers are used later by the command executor  32  (described below) to generate messages to the local program or other commands (e.g., direct database access). 
     The visual status monitor  30  monitors GUI events (e.g., Windows messages) generated by the local program. When a GUI event occurs, the visual status monitor  30  looks it up in the configuration database  36  to determine whether to generate a message to the mediator  16  for the second computing device  10 . 
     FIG. 5 is a flow digram of the operation of the visual status monitor  30 . The following explanation is numbered according to the steps of the diagram. 
     Step  50 : The visual status monitor  30  monitors GUI events generated by the local program. 
     Step  52 : When the local program generates an event, the visual status monitor  30  checks it against a predefined list of relevant event types, if the event is not in the list, it is ignored. 
     Step  54 : If the GUI event is relevant, the visual status monitor  30  attempts to match the originating GUI widget (object) to a list of active local event handlers (meaning that at least one event has already been received from that widget). 
     Step  58 : If no match was found in step  54 , the visual status monitor  30  searches records of local program widget definitions created by the window analyzer  34  in the database  36 . If a match is found, the database layout for the widget is loaded (step  60 ). 
     Step  62 : If no match was found in step  58 , the visual status monitor  30  activates the window analyzer  34  to generate a new layout. 
     Step  60 : The layout is loaded. 
     Step  56 : The local event is sent to the widget in the layout to determine whether to process it. 
     Step  64 : If the widget determines that the event should be processed, then the visual status monitor  30  looks up the event in the configuration database  36  to determine what action to perform and performs this action. 
     Step  66 : The action&#39;s results are transmitted to the mediator  16 . 
     Examples of actions includes: get embedded text/image, get enable/check state, get new position/size etc. 
     The command executor  32  receives messages from the second computing device  10  (typically resulting from a user interaction with a DHTML widget) and translates them into commands (or series of commands) executed on the local program. 
     The role of the command executor  32  therefore, is to accept events from the second computing device  10 , identify the local object associated with the event, and pass the event to that local object. The local object performs the actions required. 
     The system uses default mappings of remote actions to local commands (as detected by the windows analyzer  34  when it analyzed the UI). By default the action is to send the equivalent message to the operating system (click is a click etc.) The default action can be changed by post-processing. 
     FIG. 6 is a flow diagram of the operation of the command executor  32 . 
     Step  70 : Command executor  32  waits for event from second computing device  10 . 
     Step  72 : Is there a local object (widget) associated with the event? 
     Step  74 : Does the local object have a command associated with the event? 
     Step  75 : Is the object in a mode where it can receive input? 
     Step  76 : Execute the command. 
     The mediator  16  is a computer program that is integrated with a Web server  15 , either as part of the Web server or as a plug-in. The mediator  16  is shown in FIG.  7 . 
     The mediator  16 &#39;s role is to serve as the mediation device between the local server  18  and the second computing device(s)  10 . 
     A mediator  16  mediates between one or more local server(s)  18  and one or more second computing devices  10 . Many mediators may execute on the same physical machine. 
     The mediator  16  accepts events from the local server  18  and buffers them according to their creation time. The second computing device  10  polls the mediator  16  for changes, and the mediator  16  replies with a list of events (in XML format), which the DHTML processes. Only events required to update the DHTML to the local program&#39;s current state are sent. 
     The mediator  16  consolidates overlapping events and saves the minimal set of events required to reflect the current application&#39;s state for a new computing device  10 . If a new computing device joins an ongoing remote session (e.g., buy opening the same URL), the DHTML page that it receives from the mediator  16  reflects the current state of the remote session. 
     Working in the opposite direction the mediator  16  accepts events from the second computing device  10  and transmits them to the local server  18  where the command executor  32  identifies the object definitions associated with those events and executes the associated commands (e.g., sends messages to the local program) as was described above. 
     The mediator  16  may be configured to allow only one client to control an application while the other participants are in read-only mode or to allow several clients shared control rights. 
     Once a layout has been generated with the window analyzer  36 , its properties (in the local database and/or in the DHTML page that is sent to the client) may be post processed, i.e., customized. 
     The following are some examples of widget properties that can be manipulated: change location within the layout, change size, hide, change static text to different font/size/color/language, define special imaging hardware (such as a frame grabber or cam) that supplies images to the local program UI, define the sampling rate for transmitting an image in the local program UI to the second computing device, modify mapping of events (e.g., draw, move, access a database). 
     It should be clear that the description of the embodiments and attached Figures set forth in this specification serves only for a better understanding of the invention, without limiting its scope as covered by the following claims. 
     It should also be clear that a person skilled in the art, after reading the present specification could make adjustments or amendments to the attached Figures and above described embodiments that would still be covered by the following claims.