Abstract:
A method and an apparatus for providing bidirectional communication between a user agent and an Internet Web server. Some applications include user agent initiated on demand access to Web content without requiring a Web page reload, updating of shopping cart information, extension of displayed product information and tracking of user interaction history. Web content can be accessed in response to a user agent detectable event, including such as the selection of a text field or a button. This approach enables user agent resident JAVA script to access and process Web content before it is rendered to a user.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates generally to a method and apparatus for bi-directional communication between a user agent and an Internet Web server, and specifically to a method and apparatus for user agent initiated bi-directional communication yielding on-demand access to Web content.  
       COMPUTER PROGRAM LISTING APPENDIX  
       [0002]     Enclosed with the specification are two (2) compact discs (Copy 1 and Copy 2) which are identical. The files recorded on each of the attached compact discs (Copy 1 and Copy 2) represent a computer program listing appendix and are incorporated herein by reference. These files are compatible with the Microsoft Internet Information Services (IIS) server with Active Server Pages (ASP) support. The IIS server executes on the Microsoft operating systems including Microsoft NT Server, Microsoft 2000 Server and Microsoft Server 2003. Listed below are the files recorded on each compact disc including their names, size in bytes and date of creation.  
                                                   1)   File Name:   cls_server_content.js   Type:   JScript Script File           Size:   6KB;   Date of Creation:   Oct. 27, 2004.       2)   File Name:   default.html   Type:   HTML Document;           Size:   3KB;   Date of Creation:   Oct. 27, 2004.       3)   File Name:   demo.css   Type:   Cascading Style Sheet Document           Size:   1KB;   Date of Creation:   Oct. 27, 2004.       4)   File Name:   load_demo_content.asp   Type:   ASP File;           Size:   1KB;   Date of Creation:   Oct. 27, 2004.       5)   File Name:   nojava.html   Type:   HTML Document;           Size:   1KB;   Date of Creation:   Oct. 27, 2004.       6)   File Name:   preload.gif   Type:   GIF Image;           Size:   1KB;   Date of Creation:   Feb. 6, 2004.       7)   File Name:   READ_ME.txt   Type:   Text Document;           Size:   2KB;   Date of Creation:   Oct. 27, 2004.       8)   File Name:   style.js   Type:   JScript Script File;           Size:   3KB;   Date of Creation:   Aug. 31, 2004.                  
 
       BACKGROUND OF THE INVENTION  
       [0003]     The Internet is a decentralized global network connecting large numbers of client and server computers. The world wide web (WWW) is a system of Internet connected server computers, referred to as Web servers, that support the storage and transmission of hypertext markup language (HTML) encoded documents, referred to as Web pages. An Internet connected computer, if executing user agent and related software, can function as a Web client, or if executing Web server and related software, can function as a Web server. A user agent is also referred to as a Web browser. The related software performs operating system and communication protocol functionality required to operate as a Web client or server.  
         [0004]     Historically, the design and implementation of a user agent, a Web server and related software has undergone rapid change and evolution. Various designs, implementations and versions of user agent, Web server and related software have been developed and provided from a variety of sources over time. Users of Web server, user agent and related software vary with respect to which combination of brands and versions of software they choose to employ and how frequently they upgrade to newer versions of software. Some users continue to use older versions of software long after upgrades are available.  
         [0005]     As a result, while in operation, a user agent program typically interfaces with a variety of different brands and versions of Web server programs and a Web server program typically interfaces with a variety of different brands and versions of user agent programs. Programmed functionality that functions correctly between a particular Web server and a particular user agent, may not function correctly between the particular Web server and another user agent or between another Web server and the particular user agent or between another Web server and another user agent.  
         [0006]     The subset of functionality that can be expected to interoperate correctly between a variety of Web servers and user agents is limited to a not so clearly defined common denominator of interoperating Web server and user agent functionality, exercised between a limited set of user agents and Web servers from various sources. Furthermore, the boundaries of this common denominator are uncertain and frequently subject to change. The reliability and portability of interoperating Web server and/or user agent functionality residing outside of this common denominator is less certain.  
         [0007]     To complicate matters, the popularity of the Web is placing upward pressure upon the size and complexity of Web accessible applications and their associated Web pages. New ways of implementing Web server and user agent functionality are needed to accommodate more complex Web applications and larger Web pages in an efficient, reliable and portable manner across a variety of user agent and Web server configurations.  
       SUMMARY OF THE INVENTION  
       [0008]     The invention provides a method and apparatus of bi-directional communication between a user agent (Internet Web client) and an application server (Internet Web server). In one aspect, the invention provides for user agent initiated on demand access to Web content. The invention further enables the display of the on demand accessed Web content as a portion of a previously displayed Web page, without requiring the re-display (re-rendering) of an entire previously rendered Web page.  
         [0009]     In another aspect, applications of the invention include but are not limited to, updating the content of a shopping cart, extending displayed product information upon the selection of an item and rotating advertisements displayed by a user agent. In another aspect, applications include tracking user interaction history and interactive messaging between a user agent and a web server.  
         [0010]     In yet another aspect, the invention provides a relatively portable means for accessing Web content by circumventing the need to rely upon the HTTP body field of an HTTP message to carry the accessed Web content. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     For a further understanding of these and objects of the invention, reference will be made to the following detailed description of the invention which is to be read in connection with the accompanying drawings, wherein:  
         [0012]      FIG. 1  illustrates an arrangement of Internet components including a user agent and display monitor, an HTTP client and HTTP server, a communications link and an application server with access to various portions of Web content.  
         [0013]      FIG. 2  illustrates a Web page including three text fields that is displayed onto a display monitor via a user agent.  
         [0014]      FIG. 3  illustrates a user agent detectable event where the text field labeled “Event  1 ” is being selected via a mouse pointer.  
         [0015]      FIG. 4  illustrates the communication of an HTTP request message from the HTTP client and a following communication of an HTTP response message from the HTTP server, upon occurrence of the user agent detectable event illustrated in  FIG. 3 .  
         [0016]      FIG. 4B  illustrates an embodiment of a simplified sample of HTML script that associates a user agent detectable event with a java script action.  
         [0017]      FIG. 4C  illustrates an embodiment of a simplified sample of java script that performs actions in association with the user agent detectable event defined within the HTML script of  FIG. 4B .  
         [0018]      FIG. 4D  illustrates an embodiment of a simplified sample of ASP server script that performs actions in response to receiving the HTTP request message transmitted from the user agent.  
         [0019]      FIG. 5  illustrates the result of the user agent receiving and processing the Web content information included within the HTTP response message illustrated in  FIG. 4 .  
         [0020]      FIG. 6  illustrates an alternative method of processing the Web content information included within the HTTP response message as illustrated in  FIG. 4 .  
         [0021]      FIG. 7  illustrates a user agent detectable event where the text field labeled “Event  3 ” is being selected via a mouse pointer.  
         [0022]      FIG. 8  illustrates the result of the user agent receiving and processing the Web content information in response to the user agent detectable event of  FIG. 7 .  
         [0023]      FIG. 9  illustrates a simplified anatomy of an HTTP message that includes a start line, one or more header fields and an optional message body.  
         [0024]      FIG. 10  illustrates components of a concatenated Uniform Resource Identifier (URI) string that includes a server procedure identifier, and that optionally includes an event identifier, a date/time identifier and an HTTP object identifier residing within a header field of an HTTP request message. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0025]     In accordance with the invention,  FIG. 1  illustrates an arrangement of Internet components including a user agent  120 , a client script interpreter  130 , a display monitor  136 , a HTTP (Hyper Text Transfer Protocol) client  110  and HTTP server  150 , a communications link  190 , an application server  160  and server script interpreter  170  with access to various portions of web content  180 A- 180 N. The user agent  120  and HTTP client  110  are embodied as separate software modules that reside within a personal computer  138 . The application server  160  and HTTP server  150  are also embodied as separate software modules that reside within a network accessible computer.  
         [0026]     The user agent  120  is a software module that interacts with a user via a display monitor  136  and via other input devices including a keyboard and a pointing device, such as a mouse (not shown). The HTTP client  110  is a software module that sends and receives HTTP message transactions (messages) to and from at least one other HTTP server  150 .  
         [0027]     The user agent software  120  interoperates with the HTTP client  110  via a programming interface  115 . The programming interface  115  represents a software boundary between the HTTP client software  110  and other software external to the HTTP client  110 .  
         [0028]     The programming interface  115  enables the transfer of information between the user agent  120  and the HTTP client  110  and enables the user agent  120  to request the transmission of information by the HTTP client  110  to the application server  160  via the HTTP server  150 . The programming interface  115  also enables the user agent  120  to receive information transmitted from the application server  160  through the HTTP server  150  and through the HTTP client  110 .  
         [0029]     In a typical use scenario, during its initialization, the user agent  120  loads and displays web content to a user, in the form of an initial web page. In response to the entry of a web address by the user, the user agent  120  requests, receives and loads other web content from a web server, in the form of another web page, in accordance with the web address entered by the user.  
         [0030]     To load a web page, the user agent  120  invokes a request for the web page via its programming interface  115  with the HTTP client  110 . The web page is identified by a Uniform Resource Identifier (URI)) which is constructed by the user agent  120  and passed along with the request to the HTTP client  110 . A uniform resource locator (URL) is a type of URI.  
         [0031]     The HTTP client  110  processes the request from the user agent  120  by transmitting an HTTP request message to an HTTP server  150  that is associated with the URI. The HTTP server  150  receives the HTTP request message and transfers the URI to the application server  160  via its programming interface  155  with the application server  160 .  
         [0032]     The application server  160  receives the URI, accesses and transfers the URI addressed Web content to the HTTP server  150  via the programming interface  155 . The HTTP server transmits an HTTP response message including the addressed Web content through the Internet to the HTTP client  110 . The HTTP response message carries the Web content, such as a Web page including HTML, within its body field. The HTTP client  110  receives the HTTP response message from the Internet and transfers the Web content to the user agent  120 . The user agent  120  processes the Web content via a web page reload (display).  
         [0033]     Information is communicated between the user agent  120  and the application server  160  over the communications link  190  via the transmission of HTTP protocol request and response message transactions (messages). In a typical scenario, an HTTP request message, transmitted from an HTTP client  110 , identifies and requests the transmission of Web content from the HTTP server  150 . An HTTP response message, transmitted from an HTTP server  150 , carries the Web content to the source of the HTTP request message, namely the HTTP client  110 .  
         [0034]     Web content is typically represented in the form of Hypertext Markup Language (HTML) that is packaged into one or more Web pages and stored within one or more files residing on a network accessible computer. The HTML may encapsulate or reference other types of script languages, including JAVA script.  
         [0035]     The Web content received by the user agent  120  is processed as a Web page. In contrast to the methods of the invention, a user agent  120  typically displays a newly received web page by rendering (drawing over) and replacing all information previously displayed onto the display monitor  136 . This action is also referred to as a web page reload.  
         [0036]     Typically, the client script interpreter  130  is a JAVA script interpreter  130  that processes JAVA script associated (encapsulated) with web content received by the user agent  120 . The JAVA script interpreter  130  interoperates with the user agent  120  via a programming interface  125 . The programming interface  125  provides the JAVA script interpreter  130  with limited access to the internal functionality of the user agent  120 .  
         [0037]     Also, the server script interpreter  170  is typically an ASP (Active Server Page) script interpreter  130  that processes ASP script identified by a URI received from a user agent  120 . The ASP script interpreter  170  interoperates with the application server  160  via a programming interface  175 . The programming interface  175  provides the ASP script interpreter  130  with limited access to the internal functionality of the application server  160 .  
         [0038]     In accordance with the invention, an alternative method of bi-directional communication between a user agent and a web server is disclosed. In one aspect, the alternative method enables on-demand delivery of web content to the user agent without necessitating a web page reload by the user agent. In another aspect, the alternative method employs the HTTP protocol and employs a cookie, embodied as an HTTP message header field, to transfer web content. An in another aspect, the alternate method functions for a combination of a variety of designs and versions of Web server and user agent software  120 .  
         [0039]     In yet another aspect, this alternative method circumvents the use of a body field that resides within an HTTP response message to transfer web content. Typically, user agent software that receives and processes a body field including Web content will display the body field as a reload of an entire Web page. This type of user agent  120  behavior can be a disadvantage to the user.  
         [0040]     The increasing size and complexity of Web pages is causing increasing performance penalties for page re-loading and display. Unfortunately, functionality for accessing Web content within the common denominator of popular Web server and user agent configurations typically relies on the use of an HTTP body field within an HTTP message for carrying the Web content. The use of an HTTP body field within an HTTP message typically causes a Web page reload to be performed by a user agent  120 .  
         [0041]     Popular user agents  120  within this common denominator, including such as Microsoft&#39;s Internet Explorer 6.0 or Netscape 7.1, typically do not provide a way for JAVA script loaded within a resident Web page, to access and display other Web content carried within the body field of an HTTP message, without causing the reload and re-display (re-render) of an entire Web page.  
         [0042]     In one embodiment of the invention, a user agent  120  constructs and transmits a first communication including an HTTP request message to a (Web) application server  160 , preferably in response to a user agent detectable event. The HTTP request message includes a uniform resource identifier (URI). The URI preferably includes a procedure identifier. A procedure identifier uniquely identifies a server procedure  170  and communicates to the application server the identity of the server procedure  170  for which to execute and process the content of the HTTP request message transmitted from the user agent  120 .  
         [0043]     The server procedure  170  receives instructions transmitted from the user agent  120  via the content of the HTTP request message. Preferably, instructions are stored within the URI. The server procedure transmits a second communication including an HTTP response message in response to the instructions received from the HTTP request message included within the first communication. Preferably, the HTTP response message includes a cookie that stores any information to be delivered to the user agent  120 . A cookie is a type of header field stored within the HTTP response message. All header fields, including cookies, are stored outside of an HTTP body field of an HTTP message.  
         [0044]     In the preferred embodiment, URI information that is transmitted between a user agent  120  and a Web server  178  includes text strings packaged as “name =value” structures as shown in  FIG. 10 . A “name” can function as a parameter name, such as a name which identifies a data object, such as Web content or the name of a cookie to carry Web content. Optionally, other related information, such as a user agent event, a server procedure or time parameters can accompany the data object (web content) identifying parameter.  
         [0045]      FIG. 2  illustrates a first web page  230  that includes HTML represented text fields labeled “Event  1 ”  232 , “Event  2 ”  234 , and “Event  3 ”  236 . The first web page  230  is displayed onto a display monitor  136  via the user agent  120 . A mouse pointer  238  is also displayed onto the display monitor  136 . The web page  230  was previously transmitted from the application server  160 , through the HTTP server  150  and the HTTP client  110 , to the user agent  120 .  
         [0046]     The web page  230  includes hidden information, such as JAVA script, that is not displayed onto the display monitor  136  and stored within the user agent  120 . The JAVA script loaded into the first web page  230  includes a mapping of procedure identifiers to events associated with displayed portions of the web page  230 . Each procedure identifier represents a server procedure configured to interoperate and execute in association with the application server  160 . The server procedure can be configured to transmit web content information to the user agent  120 .  
         [0047]     HTML encodes images including graphics and text that are rendered (drawn) onto the display monitor  136  in the form of a matrix of pixels. HTML also includes and tags script, such as JAVA script, which is not displayed onto the display monitor  136 . The execution of a script is conditioned upon its context within HTML. A script can be executed upon the occurrence of an event associated with the rendered HTML field, such as a text field.  
         [0048]     The HTML loaded within the first web page  230  of  FIG. 2  includes instructions to direct the JAVA script interpreter  130  and/or the user agent  120  to render the text fields  232 ,  234 ,  236  onto the display monitor  136  and to execute a procedure within the loaded JAVA script upon the selection of any text field.  
         [0049]      FIG. 3  illustrates an occurrence of a user agent detectable event where the user agent  120  detects the selection of the text field  232 , labeled “Event  1 ”, by a user using a mouse pointing device with an associated displayed pointer  238 . The text field  232  is highlighted as indicated by a dashed perimeter border.  
         [0050]     Upon detecting the selection event, the user agent  120  invokes the JAVA script interpreter  130  to execute JAVA script loaded with the first web page  230 . The JAVA script anticipates and executes actions in response to various events associated with the first web page  230 .  
         [0051]      FIG. 4  illustrates the transmission of a HTTP request message  492 A to the application server  160  resulting from the occurrence of the user agent detectable event illustrated in  FIG. 3  and illustrates the transmission of a following HTTP response message  492 B from the application server  160 .  
         [0052]     Upon detecting the selection event of text field  232 , the user agent  120  executes the JAVA script loaded with the first web page  230  via invocation of the JAVA script interpreter  130 . In accordance with instruction from the loaded JAVA script, the JAVA script interpreter  130  associates a procedure identifier with the event that is associated with the selection of text field  232 , incorporates the procedure identifier into a URI and invokes a request for web content information addressed by the URI via the programming interface  125 . The JAVA script interpreter then waits to receive a data object, specifically a cookie, including the web content information addressed by the URI.  
         [0053]     To invoke the request, the HTTP Client  110  transmits an HTTP request message  492 A including the URI. The HTTP request message  492 A is received by the HTTP server  150 . The HTTP server  150  interoperates with the application server  160  via the programming interface  155 . The HTTP server  150  processes the received HTTP request message  492 A and transfers the URI to the application server  160 .  
         [0054]     The application server  160  processes the URI and accesses web content information  180   a - 180   n  addressed by the URI. The application server  160  then interoperates with the HTTP server  150  to construct a HTTP response message  492 B that includes the web content information addressed by the URI.  
         [0055]      FIG. 4B  illustrates an embodiment of a simplified sample of HTML script that associates a user agent detectable event with a java script action. The ServerContent function  1102  is a java script constructor method for an object named ServerContent. The ServerContent method  1102  is executed upon an event (onclick)  1104  defined by the selection of the text field having a label string equal to “Event  1 ”  1114 , via a pointing device. The text field having a label string equal to “Event  1 ”  11114  resides and is displayed as part of a Web page including the illustrated HTML script. Execution of the ServerContent method  1102  causes the java script interpreter to perform actions including the transmission of an HTTP request message  492 A within a first communication from the user agent  120  to the application server  160 .  
         [0056]     Upon execution, the ServerContent function is passed 5 parameters. The cookie_id parameter  1106  identifies a cookie to be transmitted within a second communication  492 B from the application server  160  to the user agent  120 . The event_id parameter  1108  identifies an event associated with the first communication from the user agent  120  to the application server  160 . The procedure_id  1110  parameter identifies the server procedure to execute and process the content of the first communication  492 A. The parameter  1112  is a delimiter used to separate information within the URI. The process_cookie_func parameter  1114  is the java script function that processes the cookie residing within the second communication  492 B.  
         [0057]      FIG. 4C  illustrates an embodiment of a simplified sample of java script that performs actions in association with the user agent detectable event defined within the HTML script of  FIG. 4B . During the execution of the ServerContent method, a HTTP request message  492 A is constructed and transmitted. Preferably, an empty image is constructed and used as a vehicle to construct the HTTP request message  492 A that is transmitted to the application server  160 .  
         [0058]     The ServerContent method  1102  constructs an empty image object  1120  and assigns a pointer to the image object  1120  to a data member of the ServerContent object named this.image  1122 . When a cookie is later received by the user agent, an “onload” event handler this.image.onload  1124  is executed. The ServerContent method  1102  assigns the function named process_cookie_func  1126  to the “onload” event handler (this.image.onload)  1124 . Consequently, when a cookie is later received by the user agent  120 , the process_cookie_func( ) function  1126  is executed.  
         [0059]     The ServerContent method  1102  calls the function GetRequestURI( )  1128  to return a pointer to a URI text string. The returned pointer to the URI text string is assigned to the data member of the Image object named this.image.src  1130 . This assignment causes the user agent to transmit an HTTP request message  492 A including an image content type header field for the empty image and including a URI header field, to the application server  160 .  
         [0060]      FIG. 4D  illustrates an embodiment of a simplified sample of active server page (ASP) server script that performs actions in response to receiving the HTTP request message  492 A transmitted from the user agent  120 . Upon receiving the HTTP request message  492 A, the application server  160  executes the server procedure identified by the procedure identifier  1110  residing within the URI field of the HTTP request message  492 A. The server procedure is executed via the server script interpreter  170 . During the execution of the server procedure  170 , the HTTP request message  492 A is parsed and an HTTP response message  492 B is transmitted to the user agent  120 .  
         [0061]     Summarizing the application server script of  FIG. 4D , line  1140 , the server script extracts the cookie identifier from the URI field residing within the HTTP request message  492 A. Line  1142 , extracts the event identifier from the URI field residing within the HTTP request message  492 A. Line  1144 , is a switch statement whose operation depends upon the value of the event_id  1108 . If the event_id  1108  equals the text string “Event  1 ”  1146 , then the web_content variable is assigned to the address of a text string “SERVER CONTENT  1 ”  1148 . If the event_id equals “Event  2 ”  1150 , then the web_content variable is assigned to the address of a text string “SERVER CONTENT  2 ”  1152 . If the event_id equals “Event  3 ”  1154 , then the web_content variable is assigned to an address of a text string “SERVER CONTENT  3 ”  1156 .  
         [0062]     Script line  1160 , transfers the event identifier (event_id)  1162  and the web content  1164  separated by a delimiter (|)  1166  into a cookie field of the HTTP response message  492 B identified by the cookie identifier (cookie_id)  1168 . Line  1170 , sets the content type field of the HTTP response message to “image/gif”  1172  which also causes the HTTP response message  492 B to be transmitted to the user agent  120 .  
         [0063]     The user agent  120 , upon receiving the transmitted cookie via the HTTP client  110 , generates an image onload event, which causes the execution of the image onload handler  1124  and the process_cookie_func( ) function  1126 . The process cookie_func( ) function  1126  extracts the transmitted web_content  1148 ,  1150 ,  1152  as a text string and displays the web_content onto a portion of the presently displayed web page.  
         [0064]      FIG. 5  illustrates the displayed results of receiving and processing the web content information included within the HTTP response message  492 B transmitted from the application server  160 , as illustrated in  FIG. 4 . Note that the text fields labeled “Event  2 ”  234  and “Event  3 ”  236  are unmodified.  
         [0065]     As previously stated, the loaded JAVA script instructs the JAVA script interpreter  130  to wait for the receipt of a response from application server  160 . In this embodiment, the response is an HTTP response message  492 B. The HTTP response message  492 B includes a data object that includes the web content information addressed by the URI field residing within the prior transmitted HTTP request message  492 A. The data object is a cookie residing inside of a header field within the HTTP response message  492 B.  
         [0066]     The HTTP client  110  software receives and processes the HTTP response message  492 B and extracts a cookie residing within a header field of the HTTP response message  492 B. The HTTP client software  110  then transfers the cookie to the user agent  120  via the programming interface  115 .  
         [0067]     The user agent  120  stores the cookie as a data member of a document object which is defined and instantiated within the user agent  120 . The document object is sub-classed from the window object which is also defined and instantiated within the user agent  120 . The cookie value, embodied as a character string, includes the requested first web content information.  
         [0068]     The JAVA script instructs the JAVA script interpreter  130  to check for and verify the presence of the cookie stored in association with the document object and renders the requested web content information (value of the cookie) over a portion of the displayed web page  230 , specifically over the top most text field  232 . Pixels included within the text field  232  are rendered (redrawn) to display the requested web content information. The requested web content information represents a new text field labeled “Server Content  1 ”  532 , expressed in HTML format.  
         [0069]      FIG. 6  illustrates an alternative way to process the newly received web content information included within the HTTP response message  492 A transmitted from the application server  160 , as illustrated in  FIG. 4 . Instead of drawing the text field  532  from left to right over the text field  232 , the JAVA script loaded within the first web page  230 , instructs the JAVA script interpreter  130  to draw the requested web content information from top to bottom over a portion of the first web page  230  that is separate from any previously rendered text field  232 ,  234  and  236 . In this scenario, all of the three text fields  232 ,  234 , and  236  remain unmodified after rendering (drawing) the newly received web content information.  
         [0070]      FIG. 7  illustrates a user agent detectable second event where the text field labeled “Event  3 ”  236  is selected via a mouse pointer  238 . The text field  236  is shown as being highlighted via a dashed line perimeter.  
         [0071]     Upon detecting the text field selection second event, the user agent  120  executes the JAVA script loaded with the original displayed web page  230 . The JAVA script associates a second procedure identifier with the second event that is associated with the text field  236  and incorporates the second procedure identifier into a second URI, invokes a second request for web content information including the second URI via the programming interfaces  125 .  
         [0072]     The JAVA script then waits to receive a second response from application server  160 . The second response being an HTTP response message including a second data object including second web content information transmitted to the user agent  120  from the application server  160 , in response to the second request message. The data object is a cookie residing inside of a header field within the second HTTP response message.  
         [0073]     The invocation of the second request for web content initiates transmission of an HTTP request message by the HTTP client  110  and a following transmission of an HTTP response message by the HTTP server, as described in association within  FIG. 4 . In this scenario, the second web content information is addressed by a second HTTP request message and the second web content information is transmitted as a data object residing inside of a second HTTP response message. In this embodiment, the data object is a cookie residing within a header field of the HTTP response message.  
         [0074]      FIG. 8  illustrates the displayed results of the user agent  120  processing the second web content information transmitted from the application server  160  in response to the user agent detectable second event illustrated in  FIG. 7 .  
         [0075]     The JAVA script loaded inside the user agent  120  along with the original displayed web page  230 , waits for the receipt of a data object, specifically a cookie, residing within an HTTP response message. The HTTP client  110  software receives and processes the HTTP response message, and extracts and stores a cookie residing within the HTTP response message in a manner that is accessible to the JAVA script interpreter.  
         [0076]     In this embodiment, the cookie is transferred from the HTTP client  110  to the user agent  120  via the programming interface  125 . The user agent  120  stores the cookie as a data member of a document object which is defined and instantiated within the user agent  120 . The document object is sub-classed from the window object which is defined and instantiated within the user agent  120 . The cookie value, embodied as a character string, includes the second web content information.  
         [0077]     The JAVA script software checks for and verifies the presence of the cookie stored in association with the document object and renders the second web content information (value of the cookie) over a portion of the displayed web page  230 , specifically over the bottom most text field  236 . Pixels included within the text field  236  are rendered (redrawn) to display the requested second web content information.  
         [0078]     The requested second web content information represents a new text field labeled “Server Content  3 ”  836 , expressed in HTML format.  
         [0079]      FIG. 9  illustrates a simplified structure of an HTTP message that includes a start line, one or more header fields  914 , and an optional message body  916 . The message body  916  is specified to carry web content for display by a user agent  120 . Further information regarding HTTP message structure is located within the HTTP 1.1 specification that is accessible at Internet Web address www.w3c.org and hereby incorporated by reference. Further information regarding the cookie structure is also available at www.w3c.org and at www.netscape.com.  
         [0080]      FIG. 10  illustrates the components of a concatenated uniform resource identifier (URI) string that includes a procedure identifier  1022 , and that optionally includes an event identifier  1024 , a time identifier  1026  and an object identifier  1028  residing within a header field  914  of an HTTP request message  492 A.  
         [0081]     A sample URI character string  1030  is also illustrated that includes a procedure identifier, an event identifier, a time identifier, and a data object identifier. The procedure identifier is set to the value “weather.asp”, the event identifier is set to “extended forecast” and the time identifier is set to “15:10 PM Feb. 10, 2004” and the data object identifier is set to “weather cookie”.  
         [0082]     Upon receipt of the URI  1030 , the application server  160  executes a server script  170  named “weather.asp” and provides the event identifier value equal to “extended forecast”, the date/time value equal to “15:10 PM Feb. 10, 2004” and the data object identifier equal to “weather cookie” as parameters to the “weather.asp” script.  
         [0083]     The “weather.asp” server script constructs a data object that is embodied as an HTTP cookie named “weather cookie” and sets the value of the cookie named “weather cookie” to a text string that is transmitted as a portion of an HTTP response message that is received and displayed by the user agent  120  via the client side script interpreter  130 .  
         [0084]     While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawing, it will be understood by one skilled in the art that various changes in detail may be effected therein without departing from the spirit and scope of the invention as defined by the claims.