Abstract:
Embedded links or hotspots in source Web pages are upgraded to reflect the new Universal Resource Locations (URLs) of moved target Web Pages. In a World Wide Web communication network with user access via a plurality of data processor controlled interactive display stations for displaying Web pages transmitted to receiving display stations from Uniform Resource Locations (URLs) remote from said stations, said Web pages being linkable with each other through embedded links in source Web page, a system is provided for updating said embedded links in source Web pages when the URL of a target Web page is moved. The basic system includes means associated with the target Web page of a selected link in a requesting Web page for informing the requesting page that the target page has moved together with means associated with the requesting page responsive to this informing means for forwarding the URL of the source web page of the requesting page to the original URL of the target page so that the source Web page may be thus upgraded on a one time basis the first time a requesting Web page from this source tries to link to a target page with a new URL.

Description:
TECHNICAL FIELD 
     The present invention relates to computer managed communication networks such as the World Wide Web (Web) and, particularly, to the updating of embedded links or hotspots in source Web pages to reflect the new Universal Resource Locations (URLs) of moved target Web Pages. 
     BACKGROUND OF RELATED ART 
     The 1990&#39;s decade has been marked by a technological revolution driven by the convergence of the data processing industry with the consumer electronics industry. The effect has, in turn, driven technologies which have been known and available but relatively quiescent over the years. A major one of these technologies is the Internet or Web related distribution of documents, media and programs. The convergence of the electronic entertainment and consumer industries with data processing exponentially accelerated the demand for wide ranging communication distribution channels, and the Web or Internet, which had quietly existed for over a generation as a loose academic and government data distribution facility, reached “critical mass” and commenced a period of phenomenal expansion. With this expansion, businesses and consumers have direct access to all matter of documents, media and computer programs. 
     In addition, Hypertext Markup Language (HTML), which had been the documentation language of the Internet or Web for years, offered direct links between Web pages. This even further exploded the use of the Internet or Web. It was now possible for the Web browser or wanderer to spend literally hours going through document after document in often less than productive excursions through the Web. These excursions often strained the users&#39; time and resources. In order for the Internet to mature from its great expectations to solid commercial fruition, it will be necessary for the Internet to greatly reduce its drain on time and related resources. A significant source of this drain is in the Web page itself (the basic document page of the Web). 
     In the case of Web pages, we do not have the situation of a relatively small group of professional designers working out the human factors; rather, in the era of the Web, anyone and everyone can design a Web page. As a result, Web pages are frequently set up and designed in an eclectic manner. Often, there is insufficient provision made for embedded links or hotspots in such Web pages which link to target Web pages which no longer exist or have been moved and are located at new URLs. This could potentially lead to chaotic Web browsing as the user wastes time going up blind alleys. 
     SUMMARY OF THE PRESENT INVENTION 
     The present invention provides a structured way to update the URLs pointed to by embedded links in source Web pages when the target pages of such links have moved and have new URLs. The invention also can provide the host or owner of the target page with the opportunity to refuse to have the source page embedded link updated, and provide the host of the source page with the capability of not updating its embedded link to thereby eliminate the link to a new URL. 
     The present invention is implemented in a Web communication network with user access via a plurality of data processor controlled interactive display stations for displaying Web pages transmitted to receiving display stations from URLs remote from said stations, said Web pages being linkable with each other through embedded links in source Web page. It provides a system for updating said embedded links in source Web pages when the URL of a target Web page is moved. The basic system includes means associated with the target Web page of a selected link in a requesting Web page for informing the requesting page that the target page has moved together with means associated with the requesting page responsive to this informing means for forwarding the URL of the source Web page of the requesting page to the original URL of the target page. 
     Some basic definitions are provided. The source Web page is the basic Web page which contains the embedded links; it is at the URL of the owner or host who provided the page. The requesting Web page is the same source Web page having the same embedded links which was provided from the source to a user at a receiving display station. The requesting Web page is so designated because it made the selected request via an embedded link to the target Web page which has moved and thus changed its URL. 
     The system further includes means associated with the target page for returning the new URL of the target page to the source Web page, and means associated with the source Web page for updating the selected embedded link with the new URL of the target page. Accordingly, upon the first occurrence of a selection of a link in a requesting page to a target Web page which has moved, the above system will operate to update the source Web page link with the new URL of the moved target page so that the link will be updated in any subsequent requesting Web pages resulting from the updated source Web page. 
     The present invention also may include means for forwarding the contents of the source Web page along with its URL back to the original target page URL so that the means at the target page for returning the new URL of the target page also updates the selected embedded link in the source page with said new URL. 
     In accordance with a more particular aspect of the present invention, the means associated with the target Web page for informing the requesting Web page that the target page has moved is a detour or surrogate page. In such a particular set up, the requesting Web page may have associated Web browser means for conventional accessing of Web pages, and this browser also includes the means for forwarding the source page contents and URL via this detour page to said source page. 
     The present invention may also include security means for limiting access to said source page from said target page in combination with means for permitting said return of said new target page URL and said updating of said embedded link when said access limitations are met. Thus, the host who owns the source Web page is given the capability of excluding the updating of links to the new URLs by setting access limitations. This may be accomplished through a Web server connecting the display station having the source Web page to the Web, so that the security means for limiting access and the means for permitting access are included in said Web server. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be better understood and its numerous objects and advantages will become more apparent to those skilled in the art by reference to the following drawings, in conjunction with the accompanying specification, in which: 
     FIG. 1 is a block diagram of a data processing system including a central processing unit and network connections via a communications adapter which is capable of functioning as user interactive Web station for receiving and transmitting Web pages, e.g. source, requesting and target Web pages; 
     FIG. 2 is a generalized diagrammatic view of a Web portion showing how the Web may be accessed to and from the Web stations for the requesting, old target page address, new target page address and source pages; 
     FIG. 3 is an illustrative flowchart describing the setting up of the elements needed for the program for updating of embedded links in Web pages after the change in address of the target Web pages; and 
     FIG. 4 is a flowchart of an illustrative run of the program set up in FIG.  3 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, a typical data processing terminal is shown which may function as the computer controlled network terminals or Web terminals used as any of the receiving or transmitting terminals for requesting, target and source Web pages in implementing the present invention for updating the URLs of target Web pages in the embedded links of source or requesting pages when the target pages move to new URLs. 
     A central processing unit (CPU)  10 , such as one of the PC microprocessors or workstations, e.g. RISC System/6000(™) (RS/6000) series available from International Business Machines Corporation (IBM), is provided and interconnected to various other components by system bus  12 . An operating system  41  runs on CPU  10 , provides control and is used to coordinate the function of the various components of FIG.  1 . Operating system  41  may be one of the commercially available operating systems such as the AIX 6000(™) operating system available from IBM; Microsoft&#39;s Windows 98(™) or Windows NT(™), as well as UNIX and AIX operating systems. Application programs  40 , controlled by the system, are moved into and out of the main memory random access memory (RAM)  14 . These programs include the programs of the present invention for the updating of embedded source Web page links to moved target Web pages to be subsequently described in combination with any conventional Web browser, such as the Netscape Navigator 3.0(™) or Microsoft&#39;s Internet Explorer(™). A read only memory (ROM)  16  is connected to CPU  10  via bus  12  and includes the basic input/output system (BIOS) that controls the basic computer functions. RAM  14 , I/O adapter  18  and communications adapter  34  are also interconnected to system bus  12 . I/O adapter  18  may be a small computer system interface (SCSI) adapter that communicates with the disk storage device  20 . Communications adapter  34  interconnects bus  12  with an outside network enabling the data processing system to communicate with other such systems over a local area network (LAN) or wide area network (WAN), which includes, of course, the Web or Internet. The latter two terms are meant to be generally interchangeable and are so used in the present description of the distribution network. I/O devices are also connected to system bus  12  via user interface adapter  22  and display adapter  36 . Keyboard  24  and mouse  26  are all interconnected to bus  12  through user interface adapter  22 . It is through such input devices that the user may interactively relate to Web pages, as well as the programming objects for performing functions relating to the Web page according to the present invention. Display adapter  36  includes a frame buffer  39 , which is a storage device that holds a representation of each pixel on the display screen  38 . Images may be stored in frame buffer  39  for display on monitor  38  through various components, such as a digital to analog converter (not shown) and the like. By using the aforementioned I/O devices, a user is capable of a inputting information to the system through the keyboard  24  or mouse  26  and receiving output information from the system via display  38 . 
     Before going further into the details of specific embodiments, it will be helpful to understand from a more general perspective the various elements and methods which may be related to the present invention. Since a major aspect of the present invention is directed to Web pages, transmitted over global networks, such as the Web or Internet, an understanding of networks and their operating principles would be helpful. We will not go into great detail in describing the networks to which the present invention is applicable. For details on Internet nodes, objects and links, reference is made to the text,  Mastering the Internet , G. H. Cady et al., published by Sybex Inc., Alameda, Calif., 1996. 
     Any data communication system which interconnects or links computer controlled systems with various sites defines a communications network. Of course, the Internet or Web is a global network of a heterogeneous mix of computer technologies and operating systems. Higher level objects are linked to the lower level objects in the hierarchy through a variety of network server computers. These network servers are the key to network distribution, such as the distribution of Web pages and related documentation. Web documents are conventionally implemented in HTML language, which is described in detail in the text entitled  Just Java , van der Linden, 1997, SunSoft Press, particularly at Chapter 7, pp. 249-268, dealing with the handling of Web pages; and also in the above-referenced  Mastering the Internet , particularly pp. 637-642, on HTML in the formation of Web pages. In addition, aspects of this invention will involve Web browsers. A general and comprehensive description of browsers may be found in the above-mentioned  Mastering the Internet  text at pp. 291-313. 
     A generalized diagram of a portion of the Internet, which the computer controlled display terminal  57  used for Web page receiving and browsing, is connected as shown in FIG.  2 . Computer display terminal  57  may be implemented by the computer system setup in FIG.  1  and connection  58  (FIG. 2) is the network connection shown in FIG.  1 . For purposes of the present embodiment, computer  57  serves as a Web display station and has received displayed Web page  56  containing an embedded link  34 . 
     Reference may be made to the above-mentioned  Mastering the Internet , pp. 136-147, for typical connections between local display stations to the Web via network servers, any of which may be used to implement the system on which this invention is used. The system embodiment of FIG. 2 has a host-dial connection. Such host-dial connections have been in use for over 30 years through network access servers  53  which are linked  61  to the Web  50 . The servers  53  may be maintained by a service provider to the client&#39;s display terminal  57 . The host&#39;s server  53  is accessed by the client terminal  57  through a normal dial-up telephone linkage  58  via modem  54 , telephone line  55  and modem  52 . The HTML file representative of the Web page  56  has been downloaded to display terminal  57  through Web access server  53  via the telephone line linkages from server  53  which may have accessed them from the Internet  50  via linkage  61 . 
     In continuing with the description of the Web portion shown in FIG. 2, we will describe the apparatus shown within the context of what occurs when the user selects a link to a Web page the address of which has changed. Let us assume that the user of Web page  56  at display station  57  has selected link  34 . Web page  56  is thereby the requesting Web page. The Web page request via link  34  is transmitted over the Web  50  through Web access server  49  to the old URL  59  of the target page to which link  34  points. However, the target Web page has moved to new URL  60 , location accessible from the Web  50  through Web access server  48 . However, when the target Web page was moved, there was left at the Web access server  49  which served the old URL, a surrogate or detour Web page  42 . This detour page is under the protocols and control of Common Gateway Interface (CGI)  43  of server  49 . The CGI in the server controls communications between server and resources. The CGI controls Web page interactivity. CGI functions are described in the  Microsoft Press Computer Dictionary  at pp. 85. As will be hereinafter described in detail with respect to the running of the program, the detour page informs the requesting page  56  that the Web page pointed to by selected link  34  has moved, and also requests the URL of the source page for requesting page  56 . The source page for Web page  56 , i.e. the source from which page  56  was originally transmitted over the Web, is source Web page  35  connected to Web  50  through Web access server  51 . In response to the request from detour page  42 , the URL of source page  35  is sent addressed to the old URL of the target page, and thus ends up at detour page  42 . The computer Web station  57  customarily has an associated Web browser program as described above. This Web browser has the URL of the source page  35  since it fetched requesting page  56  from the source page  35 . Since the browser also already has the contents of the source Web page  35 , it may preferably also forward the contents of the source page back to the old target page URL which ends up in detour page  42  under the control of the CGI  43  in Web access server  49 . If there are no access limitations which will be hereinafter described, then CGI  43  and detour page  42  will forward to source page  35  via Web  50  and Web access server  51  the updated new URL  60  of the target page and the embedded link position  34  which must be changed to point to the new URL. The source page  35  will be updated so that all subsequent request for Web pages from this source will have the new URL for link  34 , and, thus, not need any further modification. 
     As mentioned above, the system of the present invention does provide for security, i.e. there are means associated with the source page for placing access limitations as to which links may be updated with which new URLs. For example: there will be no updates to the following URLs. Such access limitation is conducted in a security layer  45  under control of CGI  44  in Web access server  51 . The target Web page at its new URL  60  accessing the Web  50  via Web access server  48  may also impose access limitations as to which source pages it will permit to update embedded links therein. For example: there will be no forwarding of the target page new URLs to source pages for the following URLs. Such access limitation is conducted in a security layer  47  under control of CGI  46  in Web access server  48 . 
     FIG. 3 is a flowchart showing the development of a process according to the present invention for the updating of embedded links in source Web pages to reflect changes in the URLs of moved target Web pages. Most of the programming functions in the process of FIG. 3 have already been described in general with respect to FIG. 2. A Web browser is provided at a receiving display station on the Web for accessing Web pages in the conventional manner and loading them at the display station, step  62 ; these Web pages will function as requesting Web pages. In step  63 , means are provided for the moving of the URLs of target Web pages which includes the provision of a surrogate or detour Web page  42  (FIG. 2) at the old URL of the target page. Means are provided in the detour pages for requesting the URL and HTML formats of the source Web pages of the requesting Web pages having the links to the moved target pages, step  64 . Means are provided, step  65 , in the Web browser associated with the requesting Web pages with the activated links (the Web browser associated with requesting page  56  on Web station  57  in FIG. 2) for transmitting to the detour page, the HTML format and URL of the source page  35  (FIG.  2 ). Means are provided associated with the new target page URL  60  (FIG. 2) for taking this source page HTML and URL from the detour page and for then transmitting to the source page, the new URL of the moved Web page and the upgrade of the embedded link in the source page to include this new URL, step  66 . In step  67 , security means are provided (security  45  and CGI  44  of server  51  in FIG. 2) for limiting the access of the source Web page to the URL upgrade data from the moved target page. Finally, means are provided for upgrading the source page (in the event that there is no security to limit access, or in the event of access security limitations, those access limitations being satisfied) with the moved target page URL and upgrade of embedded links to reflect this move, step  68 . 
     The running of the process set up in FIG.  3  and described in connection with FIG. 2 will now be described with respect to the flowchart of FIG.  4 . First, step  71 , the browser loads a page off the Web at a receiving display station. Then, step  72 , the user selects an embedded link on this page which now becomes the requesting page. Then a determination is made, decision step  73 , as to whether the target Web page of the selected link has moved. If No, then, step  74 , the target page is accessed and displayed. If Yes, then the detour page at the old target page URL requests the URL and HTML content of the source page which provided the requesting Web page, step  75 . In response, the Web browser associated with the Web station on which the requesting page is displayed sends the URL and HTML content of the source page to the target page via the detour page, step  76 . Then, the target page at the new location transmits to the source page, the new URL of the moved target Web page and the upgrade of the embedded link in the source page to include this new URL, step  77 . Then, decision step  78 , a determination is made as to whether access security is in effect at the source page. If No, then the source Web page and embedded link are upgraded to reflect the new URL of the target page, step  79 . If Yes, security is in effect, then step  80 , a determination is made as to whether the new URL or other access limiting conditions have been met. If Yes, the limitation conditions have been met, then the source Web page and embedded link are upgraded to reflect the new URL of the target page, step  79 . If the determination from step  80  is No, the access limitations have not been satisfied, then step  81 , a message like “Linked Page Not Accessible” is displayed. Then after any of step  81 ,  79  or  74 , a further determination is made, step  82 , as to whether another embedded link has been selected in the requesting Web page. If No, the Web page may be exited after the user completes his reading of it. However, if Yes, another link has been selected, then the process returns to step  72  via branch “A”, and the previously described process is repeated. 
     In this manner, the source Web page is upgraded only once to reflect the changed URL of a linked target page. Since the source page from which the requesting Web page was derived has the changed URL link rather than just the requesting page, then that URL link will be changed in every subsequent requesting page derived from this upgraded source page. 
     One of the preferred implementations of the present invention is in application programs  40  made up of programming steps or instructions resident in RAM  14 , FIG. 1, of Web station during various Web operations. Until required by the computer system, the program instructions may be stored in another readable medium, e.g. in disk drive  20 , or in a removable memory such as an optical disk for use in a CD ROM computer input, or in a floppy disk for use in a floppy disk drive computer input. Further, the program instructions may be stored in the memory of another computer prior to use in the system of the present invention and transmitted over a LAN or a WAN, such as the Internet, when required by the user of the present invention. One skilled in the art should appreciate that the processes controlling the present invention are capable of being distributed in the form of computer readable media of a variety of forms. 
     Although certain preferred embodiments have been shown and described, it will be understood that many changes and modifications may be made therein without departing from the scope and intent of the appended claims.