Abstract:
A simplified graphical user interface display unit which enables the user to view and change cache size relative to received cached documents and also to enable the user to track a sequence of received documents or a sequence of other computer controlled events. A data processor controlled receiving display station for receiving Web documents has apparatus for storing a sequence of received Web documents, tracking the sequence cf stored Web documents in combination with a displayed graphical unit including: a sequence of nondescriptive markers corresponding to the sequence of stored Web documents and a user interactive implementation for stepping sequentially through the sequence of markers. The receiving display station has caching apparatus of variable size and the graphical unit further includes an interactive implementation for varying the cache size which includes a space for the sequence of markers proportional in size to the size of the cache, and the implementation to vary the cache size varies the size of the space for the sequence of markers.

Description:
TECHNICAL FIELD 
     The present invention relates to computer controlled graphical user interfaces and particularly to ease of use interactive computer controlled display interfaces for tracking a sequence of data processor controlled events, such as tracking a sequence of Web documents received over the World Wide Web (Web) or Internet. More particularly, the invention relates to the tracking of received and cached Web documents or pages at a receiving display station through the graphical interface. 
     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 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 communications distribution channels and the Web or Internet (terms are used interchangeably), 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 Web documents, including media and computer programs. Web pages are now extensively used for commercial, academic and entertainment purposes. 
     In addition, because of the vast amount of information potentially available through networks such as the Internet, it is important that the presentation of the pages of a transmitted document be presented as quickly as possible on the display screen of the receiving display station and with as little effort as possible on the part of the receiving user. To this end, the Internet browser programs through which these users access the Internet are provided with caching capabilities at the receiving display station. 
     At this point, in order to better understand the factors associated with browsers and caching, a brief review of the current Internet background should be helpful. The most commonly used method of accessing and distributing data over the Internet is through the Web environment. In the Web environment, servers and clients conduct Web transactions using the Hypertext Transfer Protocol (HTTP), a common protocol for handling the transfer of various data files (e.g. text, still graphic images, audio, motion video, etc.), which may be included in Web documents. Information is formatted for transfer and presentation to a user by a standard page description language (Hypertext Markup Language (HTML)). Besides formatting, HTML allows developers to specify “hyperlinks” to other Web resources identified by a Uniform Resource Locator (URL). The URL defines a communication path to an Internet server containing information units known as Web pages. Web documents may be of any arbitrary size and may include text, graphics, media and computer programs. A Web document may include all files required to present the information requested by using the URL identifier. Retrieval from the Web is accomplished with the above-mentioned browser which is a HTML compatible application program for submitting requests for data through an URL submitted by the receiving or client display station. When such data is retrieved, the controlling Web browsers cache the documents or pages accessed at the receiving display station. Caching of pages permits the user to repeatedly view the information within a session without also repeatedly retrieving such information from the Web. The Web documents retrieved from the Internet are cached in the local memory at the receiving display station, usually in cache portions allocated in the local disk drive and in the local Random Access Memory (RAM). Most conventional Internet browsers have programming routines for evaluating incoming documents and allocating local disk drive storage and RAM for the document cache at the receiving display station. Such evaluations and allocations are based in part on the type and size of the files of data supporting the received documents. In addition, received files often contain control code indicative of cache size requirements which may be used by the browser to allocate disk drive storage and RAM portions for caching. However, all of these cache allocation procedures presuppose that the user, in setting up the browser, has set aside sufficient disk drive portions and RAM portions for such caches. For example, let us assume that the browser application using control information provided by an incoming Web page has determined that the document will require a cache having m megabytes of disk space and n megabytes of RAM. However, as it turns out, the user, in setting up the browser application, has set aside less that the n megabytes of RAM. The browser will attempt to load the document in the RAM cache, since there will be insufficient RAM cache available, the document will be loaded in the noncache portion of RAM. 
     Conventionally, many browser programs provide a customization option to specify the quantity of RAM and the quantity of disk drive storage that he wishes to set aside for cache. Since a major portion of Web users are relatively unsophisticated in computer arts, this presents difficulties to such users. Current Web browser programs have the user go through a sequence of “advanced options” dialogs in order to try to adjust the cache size to meet the demands of received Web documents involving drop down menus and dialog boxes which tend to further clutter and confuse already full graphical user interfaces. 
     SUMMARY OF THE PRESENT INVENTION 
     The present invention solves the cache size control problem by providing the user with a simplified graphical user interface displayed unit which can function, not only to provide the user with a simple means of viewing and changing cache sizes relative to received cached documents, but even further to enable the user to track a sequence of received documents or a sequence of other computer controlled events, e.g. event=any information accessed by the computer. 
     The present invention has implications beyond the tracking of received Web document caches. It is applicable to data processor controlled display systems with graphical user interfaces and provides means for tracking a sequence of data processor controlled events in combination with a displayed graphical unit including a sequence of nondescriptive markers corresponding to said sequence of events, and user interactive means for stepping sequentially through said sequence of markers. Means are provided for selecting one of said markers together with means responsive to these selecting means for displaying a description of the event represented by the marker. In this manner, the interface is not cluttered with descriptions or graphics for each event, e.g. Web document in the sequence but these descriptions may be pointed to and brought up as needed. In addition, the events themselves may be brought up and displayed as needed by such pointing means. 
     When applied to the caching of received Web documents, the invention provides a data processor controlled receiving display station for receiving Web documents including means for storing a sequence of received Web documents, means for tracking said sequence of stored Web documents in combination with a displayed graphical unit including: a sequence of nondescriptive markers corresponding to said sequence of stored Web documents and user interactive means for stepping sequentially through said sequence of markers. 
     For caching, the receiving display station has caching means of variable size and the graphical unit further includes interactive means for varying said cache size which includes a space for the sequence of markers, proportional in size to the size of said cache means, and the means for varying said cache size vary the size of the space for said sequence of markers. 
    
    
     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 implementing the receiving display station on which the received Web document may be processed in accordance with the present invention; 
     FIG. 2 is a generalized diagrammatic view of a Web portion upon which the present invention may be implemented; 
     FIG. 3 is a diagrammatic view of a Web page user interface at a receiving station to illustrate the graphical unit of the present invention; 
     FIG. 4 is a diagrammatic view of the graphical unit of the present invention shown in FIG. 3 at a series of steps in the present process; 
     FIG. 5 is a diagrammatic view of the graphical unit of the present invention at a series of steps in the present process used in controlling cache size; 
     FIG. 6 is a diagrammatic view of the graphical unit of the present invention at a series of steps in the present process which illustrate marker identification; and 
     FIG. 7 is a flowchart of a run of an illustrative process in accordance with this invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, a typical data processing terminal is shown which may function as a basic computer controlled network receiving terminal used in implementing the present invention for tracking a sequence of received and cached Web documents and for controlling cache size. A central processing unit (CPU)  10 , such as one of the PC microprocessors or workstations, e.g. RISC System/6000™ (RS/6000) (RISC System/6000 is a trademark of International Business Machines Corporation) 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 or OS/2™ operating system available from IBM (AIX 6000 and OS/2 are trademarks of 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 RAM  14 . These programs include the program of the present invention to be subsequently described in combination with any conventional Web browser, such as Netscape Communicator 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 the programs for tracking cached received Web documents and controlling cache size 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 inputting information to the system through the keyboard  24  or mouse  26  and receiving output information from the system via display  38 . The system also contains a memory cache  59 , which is variable and sized in accordance with the present invention, which is illustrated as a dashed line outline and includes a portion  41  of disk drive  20  and a portion  42  of RAM  14 . 
     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 documents, such as Web documents, transmitted over networks, 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. Reference has also been made to the applicability of the present invention to a global network such as the Web. For details on the Web, objects and links, reference is made to the text,  Mastering the Internet , G. H. Cady et al., published by Sybex Inc., Alameda, Calif., 1996. The Web is a global network of a heterogeneous mix of computer technologies and operating systems. Objects are linked to other objects in the Web 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 including programs, applets or applications. In this connection, the term documents, as used to describe data transmitted over the Web or other networks, is intended to include Web pages including displayable text, graphics and other images. This displayable information may be still, in motion or animated, e.g. animated GIF images. 
     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  56  controlled display terminal  57  used for Web page or other document display of the present invention, is connected as shown in FIG.  2 . Computer  56  and display terminal  57  are the computer system shown in FIG.  1  and connection  58  (FIG. 2) is the network connection shown in FIG.  1 . Reference may be made to the above-mentioned  Mastering the Internet , pp. 136-147, for typical connections between local display workstations to the Internet 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 is one of these known as a host-dial connection. Such host-dial connections have been in use for over  30  years through network access servers  53  which are linked  51  to the Internet  50 . The servers  53  are 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 files representative of the Web pages are downloaded to display terminal  57  through controlling server  53  and computer  56  via the telephone line linkages from server  53 , which may have accessed them from the Internet  50  via linkage  51 . Cache  59 , which serves the function of cache  59  also shown in the local display computer system described in FIG. 1, is just a local cache associated with the Web page receiving display. All standard browser programs are capable of local caching. While some form of caching is preferred, the manner of caching is not key to this invention. The user interactive graphical unit of the present invention for controlling cache size should be operable with all types of standard browser caches. 
     With reference to FIGS. 3 to  6 , we will now describe some representative user interfaces for the processes of the present invention. The current or initial received Web page  60  is shown in FIG. 3 with the user interactive graphical unit or icon  61 . It may conveniently be included in the function bar of the Web page frame provided by the Web browser interface. Then, with reference to the series of steps a through h in FIG. 4, there will be described how the present invention functions to track Web pages as they are received and cached. In step a, icon  61  is shown in the initial position of FIG.  3 . The icon has a marker  67  which is depressed and represents the current or initial Web pages, and backward and forward scroll buttons  65  and  66 ; the latter are both in the inactive or depressed positions which indicates that there are no cached documents as yet which can be scrolled in either direction. The icon  61  also includes a pair  74  of cache sizing handles which will be subsequently described with respect to FIG.  6 . In step b, the user has accessed the next Web page, e.g. by clicking on a hyperlink in the page of step a. As a result, the linked Web page becomes the current page represented by marker  67 , and the previous page of step a becomes cached and, thus, represented by marker  68  which is raised to indicate that the page is available from the cache. Backward button  65  is raised to indicate that the user may also step back to marker  68  by pressing button  65 . In the icon  61  of step c, the next linked Web page has been accessed; thus, there are now two cached previous Web pages represented by raised markers  68  and  69 . So on in step d, three Web pages represented by markers  68 ,  69  and  70  are then cached. Now, note in step e, backward scroll button  65  has been depressed by user mouse controlled cursor  71  for one iteration which results in the graphical icon  61  arrangement of step f in which the previous page represented by now depressed marker  68  has become the current or home page which will be displayed as page  60  in FIG. 3, and there are now two pages, represented by markers  69  and  70  still cached in the backward direction and one page as represented by marker  67  cached in the forward direction. Thus, both scroll buttons  65  and  66  are now raised to indicate that scrolling may be done in both forward and backward directions. Accordingly, in step g, forward scroll button  66  has been depressed by user mouse controlled cursor  71  for one iteration which results in the graphical icon  61  arrangement of step h which is a return back to the icon arrangement of step d. 
     Now, with respect to FIG. 5, there will be described an illustration of how graphic control icon  61  is used to indicate size of cache, extent of cache filling and to change the cache size. In step  5   a , the size of the cache is graphically indicated by space  73  between cache sizing handles  75 . In step  5   a , it appears that the markers  79  representing the stored documents have almost completely filled space  73  which indicates the cache is near full and should be expanded. The user then interactively grabs either of cache sizing handles  74 , as indicated in FIG. 5 b  by double cursor  72 , and moves handles  74  to the position shown in step  5   c  which results in an expanded space  73  in FIGS. 5 c  and  5   d  indicative of an enlarged cache. As set forth above, conventional browser programs provide for cache expansion based upon numeric user input. The present graphical icon provides an interactive graphical interface for such input. 
     FIG. 6 shows a simple process for identifying the Web pages or sequential documents represented by the markers and then optionally bringing back the identified pages. In step  6   a , a marker  70  is pointed to by cursor  71  which results in the display of identifier  75  which could conveniently be the URL of the page. Then, the user may choose to click on the cached page represented by marker  70 , step  6   b , which in turn makes that page the current page represented by depressed marker  67 , step  6   c , and the previously current page as represented by marker  67  in step  6   a  is now cached three iterations away in the forward direction as represented by raised marker  78  in step  6   c.    
     Now with reference to FIG. 7, we will describe a simplified illustrative process according to the present invention. When the initial or next Web page is received, step  80 , the icon  61  is set in the initial position shown in FIG. 4, step a. Then, step  81 , the arrival of the next Web page is awaited (via hyperlink selection). If the decision from step  81  is Yes, a next Web page has been selected, then, step  82 , then this next page becomes the active current or viewed page, the prior page is cached and a marker set up in the icon to represent this cached prior page. Then, after step  82  or if the decision from step  81  is No, a determination is made as to whether the user has moved to another marker, step  83 . If the decision from step  83  is No, then a determination is made, step  85 , as to whether we are at the end of the session. If Yes, then the session is exited. If No, then the process is returned to decision step  81  via branch “A”, and the next Web page is awaited. If the decision from step  83  is Yes, another marker has been scrolled to, then the Web page or document represented by the marker is displayed as the home document, step  84  (e.g. the tracking icon  61  changes, as from steps e to f in FIG.  4 ). At this point, a determination may be conveniently made, step  86 , as to whether the Web page cache is nearing its full capacity, step  86 . If No, then the process is returned to step  81 , and the next Web page is awaited. If the decision from step  86  is Yes, the cache is near full, then a determination is made, step  87 , as to whether the user has expanded the cache, e.g. via icon  61 , handles  74 , FIG.  5 . If No, then the session should be considered complete at this point and exited. If the determination from step  87  is Yes, the cache has been expanded by the user, then, step  88 , the cache storage capacity is expanded by an amount proportional to the amount represented by the amount of handle  74  movement in FIG. 5, and the process is returned to step  81 , and the session is continued. 
     For simplicity of illustration in the diagrams of FIGS. 4 through 6, the markers representative of the respective Web pages have all been shown to be of the same width on icon  61  irrespective of the size of the Web document represented. It will be understood that Web documents may vary considerably in size and content, and, thus, cache storage space which they will consume area  73  in icon  61 , FIG. 5, the markers  79  may be varied in width with the size of the documents which they represent. For example, as mentioned above, many Web pages are received with some indication of the size of the documents in bytes, or the size may be readily determined through the browser. A routine may be set up, if desired, to vary the widths of markers  79  to match the sizes of the documents which they represent. In such a case, they will still provide the user with an indication of when handles  74  are being approached by markers  79 . 
     The illustrative embodiments hereinabove have involved Web document tracking. However, the present invention is applicable to the tracking of any data processor controlled events and particularly to tracking of computer controlled events accessed by the tracking computer which have slow access times relative to the processing capabilities of the processing computer, e.g. data events moved from slower to faster storage, tape to disk or disk to RAM or from extended to current data storage. 
     One of the preferred implementations of the present invention is as a routine in an operating system made up of programming steps or instructions resident in RAM  14 , FIG. 1, during computer 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 in 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.