Abstract:
A distributed information network ( 10 ) is constructed for gathering information from sites ( 16, 18, 20, 22, 24, 26, 28, 30 ) distributed across a globally accessible computer network, i.e., the Internet. The distributed information network preferably includes a root server ( 14 ) that stores a list of multiple distributed sites each represented by metadata. A network browser ( 12 ) delivers an information search request to the root server, which in response develops a profiled information search request. The information provider of each of the distributed sites stores metadata corresponding to information content that is retrievable in response to the profiled information search request for search results derivable from the information content to which the metadata correspond. A profiled information communication link between the root server and each of the multiple distribution sites enables formation of a path for delivery of the search results to a destination site, from a site or sites represented by the metadata of the profiled information search request.

Description:
TECHNICAL FIELD  
         [0001]    This invention relates to systems and techniques for gathering and searching for information available at sites of a globally accessible information network such as the Internet and, in particular, to a distributed search architecture that facilitates real-time access to information residing on any number of distributed servers throughout the network and synthesizes the information for seamless access to specific information sought by a user.  
         BACKGROUND OF THE INVENTION  
         [0002]    Although it has exhibited explosive growth and extensively impacted the worlds of information and commerce, the globally accessible computer network known as the Internet has effectively become an unstructured victim of itself. Internet information usage has largely lost its utility because traditional search engines can neither access the vast available information pool nor qualify it adequately. The best present search engine can keep track of and access only a small fraction of Internet Worldwide Web pages (i.e., about one billion of 550 billion available documents). The accessible sites are categorized in rudimentary fashion using key words rather than intelligent assessment of content. A current common result of searches for information, even limited to the small fraction of the available information, is thousands, and often millions, of irrelevant responses.  
           [0003]    Information collection and distribution on the Internet take place as follows. A conventional Internet search engine uses software (called “spiders”) that roams the Web to gather information, which is distilled, indexed, and cataloged in a central database. An Internet search conducted by a Web user of that search engine produces results that come from the database, not from the Internet itself. The results produced are references to Internet addresses, thereby requiring the Web user to open multiple sites in search of the information.  
           [0004]    Current search engines do not include an ability to mass-search all sites and retrieve and organize the search results by content; therefore, searches are applied to all accessible information, irrespective of whether it is relevant. The result is a largely ineffective search engine effort and non-responsive returns on search queries. Examples of such traditional search engines include Northern Light™, Snap™, Alta Vista™, HotBot™, Microsoft™, Infoseek™, Google™, Yahoo™, Excite™, Lycos™, and Euroseek™.  
           [0005]    The conventional search technology is, therefore, based on a model in which the indexes, references, and actual data (in the case of commerce networks) are centralized. All queries take place at central sites, and the data distributed are not updated in real time (and are typically stale) and usually require reformatting. The Internet is at best a frustrating search environment because the data reside in multiple formats and in a distributed world.  
           [0006]    For applications in commerce, the existing Internet architecture can accommodate only a small fraction of the business participation that would otherwise be available to produce consumer benefits arising from competition. The Internet as a consequence effectively serves only the large dominant players, while effectively excluding everyone else. Part of the e-commerce perception is that virtually anything can be purchased over the Internet. While the perception is accurate, it ignores the fact that bias in the current system locks out a much greater part of the marketplace than it serves. Business to business commercial utilization of the Internet consists largely of e-mail communications.  
           [0007]    For applications in delivery of services, particularly as various governmental entities have attempted to use the Internet, the lack of sensible structure is especially notable. These situations do not exist through the fault or incompetence of users but again stem from an inherent and systemic limitation of the “centralized” Internet.  
           [0008]    The efforts of traditional search sites to retain and attract more consumer attention and thereby generate more advertising revenue have caused the attempt to centralize all online information to rise to the point of conflict. As stated above, the growth in the volume and the diversity of Internet content now lead to searches generating thousands of pages of results that encompass only a fraction of the overall body of relevant information. The market needs access to additional organizational structures, but the current system makes these requirements impossible to meet. Traditional search sites are designed and predicted to lead to further centralization, which will exacerbate the information accessibility problem.  
           [0009]    Conventional wisdom has been that speed can offset the growth of Internet information. The industry emphasis has been on hardware improvements rather than next generation software. Five years ago, a state of the art personal computer used a 166 MHZ microprocessor chip. Currently, 800 MHZ microprocessor chips are standard, and 1,000 MHZ microprocessor chips are expected to be available soon. Ironically, while currently available machines can search for information much more quickly, they also create information at a rate consistent with their speed. They are in effect helping the problem keep pace with the solution. Insofar as emphasis has been placed on software, it has been to improve applications within the current architecture or to offer and market e-commerce alternatives within the current architecture. As a consequence, all such efforts are impeded before they begin.  
           [0010]    Because of the sheer size of the Internet and the spiders operate from a central location, the spiders can cover only a small fraction of the entire Internet. The resulting database of search results is inherently limited not only in size but also in freshness. The required tradeoffs are self-defeating. Making the database broader and deeper would require excessive “roaming” time so that the information would become stale. Keeping the information fresh would require searching a smaller fraction of the available Internet documents, thereby making the results less comprehensive.  
           [0011]    Total information is now growing at an exponential rate. Most of the new information winds up in the inaccessible category. There is no assurance that updated information will “bump” outdated information from the accessible information pool. The average age of newly returned Worldwide Web links is 186 days. The milieu is frequently one of old information, insufficient information, disorganized information and, in short, unmanageable information. There is a pressing need, therefore, to fold the existing Internet into a new world of efficient organization that will competently manage future generations of growth.  
         SUMMARY OF THE INVENTION  
         [0012]    The present invention is a distributed information network that is constructed for gathering information from sites distributed across a globally accessible computer network, i.e., the Internet. These distributed sites are equipped to host and maintain their own information, while other associated technology enables inclusion of individual sites in mass Internet searches.  
           [0013]    A preferred embodiment of the distributed information network includes a root server that stores a list of multiple distributed sites each of which represented by metadata corresponding to directly or indirectly available information content. Metadata are extended properties of a data object, which could be, for example, a single file, an object in a database, an e-mail message, a piece of memory, or a description of information content on a site. Metadata may be so simple as to represent a file name or size or so complex as to represent file author or database schema information. A user&#39;s network browser delivers an information search request to the root server, which in response develops a profiled information search request. Each one of multiple distributed sites is implemented with an information provider that is remotely located from the root server. The information provider of each of the distributed sites stores metadata corresponding to information content that is retrievable in response to the profiled information search request for search results derivable from the information content to which the metadata correspond. A profiled information communication link between the root server and each of the multiple distribution sites enables formation of a path for delivery of the search results to a destination site, such as the network browser, from a site or sites represented by the metadata of the profiled information search request.  
           [0014]    The above-described preferred embodiment of a distributed information network provides an Internet search engine that advantageously uses the inherent strengths of the Internet—a distributed architecture. When a search request is initiated, the search engine queries multiple sites simultaneously and looks for the information, in whatever data format it resides, finds the information, and then returns the actual document to the user. A multithreaded-enabled client web browser sends simultaneous queries to distributed servers, thereby removing the bottleneck of a centralized server or searching body. The client web browser also manages the download of information from the server and, therefore, enables it to handle a dramatically greater number of clients than that handled by traditional present-day models. This distributed search application addresses the fundamental deficiencies in current Internet coverage: poor access, stale data stores, irrelevant information, and unstructured repositories of underutilized information.  
           [0015]    The search architecture of the invention includes the ability to conduct a decentralized search of live data (structured or unstructured), search on specific parameters (price, brand, availability, reviews, and other such parameters), and present search results in clean, organized form on one display screen. The search architecture in effect moves the query to the location of the information. A user can continuously apply filters to search results and focus in on the specific product or information for what the user is looking.  
           [0016]    Advantages of the distributed search architecture include conformance to industry standards; vertical and horizontal scalability, without requirements for additional hardware or degradation of performance; use of available bandwidth of the Internet instead of the available bandwidth of any one central search engine, thereby eliminating possible bottlenecks inherent with any centralized solution; delivery of accurate, current information; requirement of lower infrastructure resources (servers, electronic storage, and bandwidth) as a consequence of queries being distributed throughout the network; no performance degradation in relation to the number of sites searched and no limitations imposed on the number of sites searched; no effect of down sites on search results; and client management of all data sorting, filtering, and comparisons, thereby eliminating redundant network traffic and data processing currently required by present day architectures.  
           [0017]    The use of distributed sites represents a fundamental change from the present central mass storage method and opens the doors to the remaining large fraction of stored but inaccessible information with the current architecture. The result is a creation of vast areas of new opportunities within e-commerce and corporate information sharing through information portals. Such new opportunities include applications in music and movie distribution, software application distribution, instant messaging, collaboration, auctions, individual commerce, parallel searches, and e-mail. This changeover allows more sophisticated business to business (B2B) and consumer e-commerce interaction.  
           [0018]    The present invention provides an opportunity to establish new standards and methods for gathering information from distributed sites across the Internet. The invention is adapted to keep pace with current Worldwide Web growth and has applicability to virtually every merchant, corporation, and consumer. The distributed sites are able to host and maintain their own information while the invention allows the individual sites to be included in mass Internet searches. The invention is implemented as a single distributed architecture, with its own intelligent search engine, to manage digital information and uses software for the Internet and its content management to achieve responsive results from Internet searches.  
           [0019]    The distributed architecture can be analogously described, conceptually, as being similar to telephone area codes or postal service zip codes. The difference is that coding is content specific rather than geography specific. The distributed information network architecture can search existing sites, including the 84% currently inaccessible sites, intelligently categorize them according to content, and codify them as required with single or multiple codes for future intelligent retrieval. Future sites can be readily integrated as they come online to be immediately available, thus ending the present 186-day lag. If desired, commerce users can download e-commerce web site software that permits custom presentation of the full inventory of products offered. A customer shopping for a particular product can across multiple vendor sites immediately compare, for example, vendor prices, warranties, return policies, and shipping costs.  
           [0020]    The distributed search network and technology has applicability to e-commerce and serves to eliminate bias, thereby resulting in “Main Street” and individual commerce being served as well as the electronic superstores that currently dominate product offering and services. Main Street and individual sellers have little chance to create visibility within the confines of the current marketplace because search results are marketed and there is no provision for actual “live” product comparisons. The invention presents a substantial opportunity for search results leading to an actual product, rather than a web site, and thereby offers solutions that eliminate bias and lead to a level playing field where sellers can be assured their sites and products are included.  
           [0021]    The invention permits sellers and corporations to direct control over the timing and context of their own information and facilitate a trend of “de-centralization” as a natural evolutionary step for the Internet. The search engine also functions within an information portal that will allow efficient B2B cooperation. For instance, component vendors no longer require direct system links with OEMs to ensure timely and adequate supply. The invention allows immediate selection of category, product line, and brand name. All vendors enrolled in the architecture are represented for comparison. The invention makes possible substantial vertical markets to exist for its solutions where private networks of searchable and structured information can be used to create supply and procurement systems and information research networks. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    [0022]FIG. 1 is a block diagram of an example of a distributed application network configured in accordance with the present invention.  
         [0023]    [0023]FIG. 2 is a block diagram showing in greater detail the internal structure of the root server shown in FIG. 1.  
         [0024]    [0024]FIG. 3 is a block diagram of a level one site server, showing the program flow when a distributed query is performed in the distributed application network of FIG. 1.  
         [0025]    [0025]FIG. 4 is a block diagram of a level two site node server that has no sites registered with the site provider and has no child server.  
         [0026]    [0026]FIG. 5 is a block diagram of a site server on which coexist several different providers for a wide variety of information sources.  
         [0027]    [0027]FIG. 6 is a block diagram showing a site servers parser manager and its parsers for a file accessor and its data stores for use in supporting an explanation of a method of accessing and parsing data in accordance with the invention.  
         [0028]    [0028]FIG. 7 is a block diagram showing in greater detail the structure and organization of certain component blocks of FIG. 6.  
         [0029]    [0029]FIG. 8 is a block diagram of a distributed information network composed of an e-commerce network, a business to business network, a business to business supply side network, and an information network implemented with public and private servers.  
         [0030]    [0030]FIG. 9 is a block diagram showing in greater detail the internal structure of an information application egg group of the distributed information network of FIG. 8.  
         [0031]    [0031]FIG. 10 is a flow diagram of a session authentication and security process for peer to peer network communications in accordance with the invention.  
         [0032]    [0032]FIG. 11 is a flow diagram outlining the steps of a process for providing file sharing security in a distributed environment. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0033]    [0033]FIG. 1 is a block diagram of an example of a distributed application network  10  configured in accordance with the invention and showing information flow paths in response to a particular end user request. An application network is a collection of servers that participate in a particular application of the distributed information network of the invention. Examples of an application network include an e-commerce network, an information portal, or a peer to peer (P2P) network. Network  10  is a hierarchical system of distributed servers that store network content and communicate with other servers in the network. The hierarchical system is one in which a server can have any number of child servers, each of which can have any number of its own child servers, with an unlimited number of successive levels of dependent servers possible. This structure helps distribute the storage of content and the processing load on the network. FIGS.  2 - 4  show in greater detail the internal structures of, respectively, root, site, and site node servers represented as system component blocks in FIG. 1. FIGS.  1 - 4  support the following explanatory overview of the core technology implemented in a distributed Internet architecture operating in response to a typical search for content by a user.  
         [0034]    With reference to FIG. 1, network  10  includes an operating system client, which is typically a web browser or client applet  12  that is stored in an end user&#39;s computer. The client applet is client-side software that is preferably written in JAVA language code (but could be written in any other software development language) and allows any computer to participate in the network. Client applet  12  is the software interface between the user and the application network. A root server  14  located remotely from the user&#39;s computer is implemented with a root profiler that stores a list of multiple sites distributed across a global computer network, such as the Internet. Root server  14  is the single “ancestor” of all servers and child servers and is the main point of entry for client applet  12 . Root server  14  has three children, site servers  16 ,  18 , and  20  representing level one servers of Company A, Company B, and Company C, respectively. Site servers  16 ,  18 , and  20  represent examples of information sources listed in the root profiler of root server  14  and qualified in response to a user&#39;s specific request. Skilled persons will appreciate that there are many different candidate information sources, such as, for example, state and other government networks, corporate data, commercial and educational information web sites, e-commerce web sites and individual desktop personal computers (PCS).  
         [0035]    Each of site servers  16 ,  18 , and  20  is implemented with an information provider that stores retrievable metadata, which is kept current by and under control of the company with which the site server is associated. Metadata are information about the locally resident content stored on each site server and the content on any child servers a site server might have. There are two basic types of metadata, which are topic data and site-profile data. A topic is a unit of content served up by an application network. The topic database at a site server stores information about the type of information stored at the site and its child sites. (In FIGS. 2 and 3, the topic databases are labeled, respectively, “Topic Database” at root server  14  and “Content Type” databases at site server  16 .) The site-profile database stores information about which ones of the servers, including itself and its children, store what types of topics. Site servers  16 ,  18 , and  20  provide, therefore, a set of metadatabases, which are databases of information about the information that is stored and exchanged on network  10  and which are databases that keep track of where particular types of information are stored on network  10 . The root profiler identifies site servers  16 ,  18 , and  20  by content-specific codes that represent topic profiles indicative of the information content site servers  16 ,  18 , and  20  contain. Site server  16  of Company A is associated with a level two server, Site A node server  22 . Site server  20  of Company C is associated with two level-two servers, Site C node server  24  and Site C child server  26 . Site C child server  26  is associated with two level-three servers, Site C2 node server  28  and Site C2 node server  30 .  
         [0036]    [0036]FIG. 1 illustrates the operation of network  10  when a user causes web browser  12  to request from root server  14  the identification of qualified servers relating to a specific topic. Root server  14  sends the request to site servers  16 ,  18 , and  20 , all of which root server  14  identified as qualified in response to the topic the user requested. (The arrow-tipped broken lines drawn between root server  14  and each of site servers  16 ,  18 , and  20  represent pathways for updating metadata about sites on the network and relationship activity (e.g., transaction tracking and reporting) that links them and does not indicate search pathways.)  
         [0037]    Network  10  processes a user topic query request as follows. A network user browses a web page on root server  14 . If it is not already installed on the user&#39;s personal computer, the client applet is downloaded and installed (with the user&#39;s permission). Client applet  12  downloads a current topic database  48  from root server  14 , displaying the topic structure typically as a hierarchical tree of categories. Client applet  12  then allows the user to navigate the category tree until the user finds the category of topics of interest. As soon as the user navigates to a category level that is of sufficient specificity to be associated with particular site servers, client applet  12  sends either an automatic or user-commanded query to root server  14 . When client applet  12  indicates a search, the query request is sent to root server  14  for a list of site servers that qualify. Root server  14  returns to client applet  12  a packet of information containing a list of all qualified site servers on application network  10  that have the type of content requested. Site servers  16 ,  18 , and  20  represent the site servers appearing on the list in the example illustrated in FIG. 1. As the user navigates down the tree toward the topic level, client applet  12  uses the available metadata to display an attribute selector. This lets the user select specified attributes, features, characteristics, specifications, and other aspects of the topic that enable the user to narrow the focus of the search. When the topic query is sufficiently specific, the user executes it. The user&#39;s client applet  12  in this example compiles a list of site servers  16 ,  18 , and  20 , performs a topic query on each of them, and awaits the results site servers  16 ,  18 , and  20  produce. Processing of the topic query request entails directing it to all three of the level one site servers  16 ,  18 , and  20 . Site servers  16  and  20  then pass the topic query request to the three level-two servers  22 ,  24 , and  26 . Site C child server  26  further passes the topic query request to Site C2 node servers  28  and  30 . This process takes place while bypassing any servers that do not have the pertinent content. The results obtained are directed back, again while bypassing all other servers, to client applet  12  for display to the user. The user can then review the search results and click through to any of the linked content sources. Administration application software  32  (FIGS. 2 and 3) communicates with root server  14  to keep track of the number and types of topic search requests processed, as well as update the metadatabases on the site servers.  
         [0038]    [0038]FIG. 2 is a block diagram showing in greater detail the internal structure of root server  14 . FIG. 2 shows the program flow when a site server list is compiled in root server  14  and delivered to client applet  12  in response to a topic query request made by a user. With reference to FIG. 2, the topic query request initiated by client applet  12  passes through the Worldwide Web to a web server  50  on which web pages associated with root server  14  are stored. (Web server  50  may be physically separate from or a part of root server  14 .) Web server  50  passes the topic query request to root server  14 , which uses its information providers to query its database for all servers that match the request type. Root server  14  is implemented with a query parser interface  52  that includes a site provider  54  and a core provider  56  to interpret the topic query request. Each of site provider  54  and core provider  56  is preferably a JAVA language-based program that runs on root server  14 . The site provider  54  and core provider  56  components of query parser interface  52  consult the local metadatabases to determine which site servers lead to the specific type of topics content requested. This entails identifying site servers that themselves have the right topics or are associated with descendant servers that have the right topics. Site provider  54  identifies site servers corresponding to the content-specific codes representing the topic profiles, and core provider  56  identifies properties of the topics. Query parser interface  52  accesses and retrieves information from topic database  48  and a site profile database  60  to assemble the packet of information containing the list of qualified site servers to search. The packet of information represents a profiled information search request generated by root server  14 . An administrative interface module  62  contains software for maintaining the databases and reporting on the frequency of access to them.  
         [0039]    An example of a topic query request would be the identification of sellers of VCRs of a particular type. Site provider  54  retrieves from site profile database  60  the identities of site servers of companies that sell VCRs. Core provider  56  retrieves from topic database  48  the properties (e.g., cost of purchase, compact disk compatibility, and stereophonic sound capability) of the specified type of VCR. Root server  14  returns the assembled packet of information to the user by way of web server  50 . The topic query request is then distributed through client applet  12  to the level one servers of the sites identified.  
         [0040]    [0040]FIG. 3 is a block diagram of level one site server  16 , showing the program flow when a topic query requested is performed. (Although site server  16  has only node server  22 , FIG. 3 shows in phantom lines two child site servers of greater hierarchical level to demonstrate network scalability.) With reference to FIG. 3, site server  16  receives from client applet  12  a topic query request made by a user and profiled by root server  14 . Site server  16  is implemented with a query parser interface  78  and processes the topic query request by determining whether site server  16  itself or an associated child node site server can support the topic query. Query parser interface  78  includes a site provider  82 , a content Type A provider  82 , a content Type B provider  84 , and a content Type C provider  86 , all of which represent different ways of collecting content information by bridging a topic query request and a database. For example, content Types A, B, and C may represent, respectively, e-commerce information, data, and site content (HTML).  
         [0041]    Site provider  80 , e-com provider  82 , data provider  84 , and HTML provider  86  access and retrieve content information from, respectively, a child site database  90 , a content Type A (an e-com) database  92 , a content Type B (data) database  94 , and a content Type C (site content (HTML)) database  96 . Each child node site server returns its search results to server  16 , as is described below with reference to FIG. 4. The information providers of query parser interface  78  and the search results received from any child node sites are the sources from which site server  16  builds a site list that returns the complete search results to client applet  12 .  
         [0042]    When the content at any server changes, a site administrator uses administration application software  32  (FIGS. 2 and 3) to update the metadatabases on the site server. Those updates are automatically sent to all associated parent servers of greater hierarchical levels. An administration interface of each server (administrative interface  98  of server  16 ) at each level (and administrative interface  62  of root server  14 ) updates the local metadatabases. Each server along a lineage always has a current picture of the content available locally and through its child sites. Root server  14  hosts, therefore, complete and current metadatabases of what kind of information is stored on network  10  (in topic database  48 ) and the first step on the path to where the information is stored on network  10  (in site profile database  60 ).  
         [0043]    [0043]FIG. 4 is a block diagram of a level two Site A node server  22 , which has no site registered with its site provider  100  and has no child server. With reference to FIG. 4, a content Type A (e-com) provider  102 , content Type B (data) provider  104 , and content Type C (HTML) provider  106  residing in query parser interface  108  of Site Angle server  22  provide qualified topics to be searched in a content Type A (an e-com) database  110  and a content Type B (site) content database  112 . The results obtained from searches of databases  100  and  102  are returned to parent site server  16  for delivery to client applet  12 . An administrative interface  114  updates the local metadatabases.  
         [0044]    Site server  16 , together with Site A node server  22 ; site server  20 , together with Site C node server  24 ; and site server  20 , together with Site C child server  26  and site C2 node  30 , each form a local information network in accordance with the invention.  
         [0045]    Site server  16  can be implemented with a local root profiler, which as indicated in FIG. 1, includes Site A node server  22  in its list of distributed local sites. Site A node server  22  is also expandable to accommodate its own local root profiler but in the example depicted in FIGS. 1 and 4 provides only local metadata in response to a local profiled information search request accompanied by an information content-specific local code corresponding to the information content of the local metadata.  
         [0046]    Site server  20  can be implemented with a local root profiler, which as indicated in FIG. 1, includes Site C node server  24  and Site C child server  26  in its list of distributed local sites. Similarly, Site C child server  26  can be implemented with its own local root provider, which as indicated in FIG. 1, includes Site C2 node servers  28  and  30  in its list of distributed local sites. Each of Site C2 nodes  28  and  30  is also expandable to accommodate its own local root profiler.  
         [0047]    The sites included in the level one servers and servers in successive levels function, therefore, either to list distributed sites or to provide metadata for processing by the distributed network.  
         [0048]    [0048]FIG. 5 shows a site server  120  on which coexist multiple different providers for a variety of information sources. The structural organization of site server  120  facilitates the capability of a distributed information network of the invention to access and extract useful information from a particular information source once it has been discovered. With reference to FIG. 5, site server  120  has a provider manager  122  that routes an incoming search query to an appropriate one or appropriate ones of the five providers shown in the example presented. The providers include a provider  124  to an e-commerce database A  126  and a B2B database A  128 , a provider  130  to a WINDOWS file system  132 , a provider  134  to a UNIX file system  136 , a provider  138  to a content database  140 , and a provider  142  to an e-commerce database B  144 . Each of providers  124 ,  130 ,  134 ,  138 , and  142  has a respective accessor  124   a ,  130   a ,  134   a ,  138   a , and  142   a . An accessor is capable of finding, opening, writing, and reading an object irrespective of the type of platform or data store. (A data store is a storage mechanism, such as a file system, database, e-mail system, or zip file, that may contain data in an organized format.) An accessor also has the ability to “spider” (i.e., examine the contents of) a data store or search for a single data object. (A data object is a single file, an object in a database, an e-mail message, a search result, or a piece of memory.) The appropriate providers for responding for a particular search query use their accessors to query their associated information sources or data stores. The accessors translate between the query language of a root server of the distributed information network and the query language of a data store. This implementation facilitates access to any information source and is described in detail below with reference to FIGS. 6 and 7.  
         [0049]    File system accessors  130   a  and  134   a  use a parser manager  146 , which functions as a computer language interpreter and in the example presented includes six parsers equipped to recognize documents in six different software file formats. A parser knows how to read the contents of a data object and thereafter extract metadata and store them in a common format. The six parsers include WORD document, EXCEL document, JPG Image, MP3 audio, POWERPOINT, and PDF parsers. Irrespective of where and how a particular file is stored, parser manager  146  directs the file to the appropriate parser. For example, if a file represents a WORD document, the WORD document parser extracts the metadata for the provider. The providers, together with parser manager  146 , enable access to any type of information including: static web pages, word processor or spreadsheet documents, images, music, video, and legacy database information. The providers are expandable to automatically handle new data types.  
         [0050]    The providers of the distributed information network allow retention by the information source itself of ownership of all data. The providers act as a window directly into the data source, thereby enabling information sources to control who has access to particular information and to control how results are displayed.  
         [0051]    The role of an accessor stems from the existence of data in many forms and at many locations in many platforms. As stated above, the present invention implements a technique that accesses and parses the data in a consistent and secure manner and thereafter stores the metadata in a common format. FIGS. 6 and 7 support the following explanation of this technique. FIG. 6 is a block diagram of an exemplary site servers parser manager and its parsers for a file accessor and its data store. FIG. 7 is a block diagram showing in greater detail the structure and organization of a provider manager with seven accessors and a parser manager with seven parsers.  
         [0052]    With reference to FIG. 6, a site server  200  functions to deliver to a parser manager  202  information from a data store  204  through an accessor  206   a . (Accessor  206   a  is one of multiple accessors shown in FIG. 7.) A provider (not shown) in site server  200  is also connected to database  208  in a structural arrangement analogous to that shown for site server  120  and databases  126 ,  128 ,  140 , and  144  in FIG. 5. Parser manager  202  directs information to multiple parsers, including, for example, a WORD documents parser  210 ; an e-mail parser  212 ; a database data parser  214 ; and other information parsers  216  representing collectively from FIG. 7 a web page parser  218 , an archived data parser  220 , LOTUS Notes or EXCHANGE databases parser  222 , and an images, movies, or music parser  224 . With reference to FIG. 7, an accessor manager  230  maintains a list of registered accessors, of which there are seven shown by way of example. Accessors  206   a ,  232   a ,  234   a ,  236   a ,  238   a ,  240   a , and  242   a  are associated with, respectively, a file system data store  206 , an e-mail system data store  232 , network files data store  234 , databases data store  236 , LOTUS Notes data store  238 , an Internet server data store  230 , and zip files data store  232 .  
         [0053]    With reference to FIGS. 6 and 7, the technique for accessing and parsing data is a mechanism for walking (i.e., reading a file system) a data store and parsing it, irrespective of the location of the data or their type. By handling data stores and data objects generically, the system passes around a generic object that represents a data object. This data object is capable of accessing itself from the data store by loading and saving the information and to parse its data for extended properties. Process block  250  represents a spider event that initiates the process of accessing a data store and parsing it. A spider event begins with a starting location and a starting accessor. There is one accessor associated with each data store. An accessor has the ability to spider a data store or search for a single data object.  
         [0054]    An accessor walks a list of objects on its data store and either creates an alias (called a “Moniker”) out of the object or loads another accessor to process the object. A Moniker is an object that wraps a data object, which may be a file, a piece of data in memory, or an abstract link to any type of object. The Moniker is what is passed among accessors, parsers, servers, and clients. Accessors have a find first/find next interface that returns Monikers or references to other accessors. Accessors also have a user interface with the ability to include or exclude data and set starting and ending locations when processing a data source.  
         [0055]    Accessor manager  230  maintains a list of all registered accessors and loads them as necessary. The Moniker is created by the accessor. The accessor then indirectly loads a parser. The Moniker may be shared among remote servers or clients. With a Moniker, one can ask for file information, extended properties, or any other dynamic information.  
         [0056]    Parser manager  202  can load a parser for a given file type. A parser processes a file by extracting data. A parser may support many data types or a single specific data type. There may be multiple parsers supporting the same data type, and parser manager  202  determines the best parser based on the platform, installed components, or other factors. Any parser can use any accessor.  
         [0057]    The use of an accessor, parser, and Moniker provides an ability to walk any data store or data stores imbedded in other data stores (e.g., zip files on file systems or e-mail) and open and parse data irrespective of the file format.  
         [0058]    [0058]FIG. 8 is a block diagram showing a distributed information network  300  composed of several application networks, demonstrating a distributed Internet architecture representing a hybrid of centralized and peer to peer models. With reference to FIG. 8, distributed information network  300  includes an internal network  302  composed of a root server  304 , a stage server  306 , an e-commerce hosted shopping site server  308 , e-commerce datafeed site servers  310 , and information public sub-root servers  312 ,  314 , and  316 . Root server  304  operates in the manner described above for root server  14  of FIG. 1, and stage server  306  enhances metadata collected from various servers in network  300 .  
         [0059]    In particular, stage server  306  uses models, model attributes, and field sets to perform various information manipulations, comparisons, arrangements, and other processes for presentation to the client user the retrieved information in a way that bridges the information gap inherent in current prior art search engines. As indicated in FIG. 8, to administer its operation, stage server  306  is organized by clients, such as e-commerce, business to business (B2B), and community information. B2B e-commerce refers to trade that is conducted between a business and its supply chain or between a business and other business end-customers. E-commerce hosted shopping site server  310  is an online marketplace that introduces consumers directly to products. Site server  310  provides through root server  304  real-time, direct access to each subscribing merchant&#39;s catalog that leads to an actual product listing, rather than a link to a web site. The information provider technology described above enables advanced custom tailoring of information such as dynamic pricing and category filtering. E-commerce datafeed site servers  310  store in internal network  302  client-provided information as an accommodation to information providers that do not want live searches conducted at their sites.  
         [0060]    Information public sub-root servers  312 ,  314 , and  316  represent three examples of sub-root servers for public community interest groups, each of which potentially having a growing number of information providers and information consumers. These sub-root servers, which are hosted and administered by a network manager and operate in cooperation with root server  304 , give real-time, direct access to every information source in its network to ensure all current information is accessible with no dead links returned.  
         [0061]    E-commerce hosted shopping site  308  and information community sub-root servers  312 ,  314 ,  316 , and  354  represent an information portal that opens up the Internet such that any user can publish any type of information or access any type of device. The information portal can support an indefinite number of information types (e.g., web sites, file servers, databases, and image files) and any number of information sources, irrespective of whether they are structured or unstructured.  
         [0062]    Root server  304  has multiple level one servers, including a commerce site server A  318  and commerce site server B  320 .  
         [0063]    Commerce site server A  318  represents a B2B e-commerce level one server with an e-commerce provider  322  and B2B provider  324  that are analogous to the providers described with reference to site server  16  of FIG. 3. Commerce site server A  318  has a level two commerce child site node server A1  326 , which has a communication link with e-commerce provider  322  and represents an e-commerce private information network. Commerce child site node server A1  326  has an e-commerce provider  328  and information provider  330  that are analogous to the providers described with reference to child site node server  22  of FIG. 4. Commerce child site node server  326  is a private internal network in which, for example, the employees of the company owner of commerce site server A can access companywide internal proprietary documents, such as EXCEL documents. Commerce site server A  318  is shown having a communication link with an e-commerce private shopping client  332  that shops for only the products of the entity that owns commerce site server A and its child sites.  
         [0064]    Commerce site server B  320  represents a B2B e-commerce and B2B supply side e-commerce level one server with an e-commerce provider  334  and B2B provider  336  that are analogous to the providers described with reference to site server  16  of FIG. 3. Commerce site server B  320  has two level-two child site node servers  338  and  340 , both of which have communication links with B2B provider  236  and represent B2B suppliers. The two B2B supplier servers  338  and  340  can establish a B2B supply side connection by which the entity that owns commerce site server B  320  can shop for supplies. Commerce site server B  320  is shown having a communication link with a B2B private shopping client  342  that shops for only the products of the entity that owns site server B  320  and its child sites.  
         [0065]    An e-commerce shopping client  350  and a B2B portal shopping client  352  each shop multiple markets through root server  304 . E-commerce shopping client  350  enables business to consumer (B2C) retail shopping of multiple sites in multiple markets. B2B portal shopping client  352  enables B2B shopping of multiple sites in a given market and thereby creates a market making opportunity for an unlimited network merchant participants to create a live and dynamic network catalog of products.  
         [0066]    [0066]FIG. 8 shows information public sub-root servers  312 ,  314 , and  316  and an information private sub-root server  354  associated with what are called information application egg groups, each of which is composed of a client and a node server. An information application egg group  356  has a communication link with information public sub-root server  312 ; an information application egg group  358  has a communication link with information public sub-root servers  356  and  358 ; and an information application egg group  360  is associated with private sub-root server  354 . Peer to peer (P2P) communication links  362 ,  364 , and  366  are established, respectively, between information application egg groups  356  and  358 , between information application egg groups  358  and  360 , and between information application egg group  356  and information provider  330  of commerce child site server A1  326 . P2P communication links are connections between stand alone computers by which a file can be downloaded from one of the computers to the other without action of a root server. Information private sub-root server  354  hosts and administers its own server and determines who gets access, rights, and privileges associated with it.  
         [0067]    [0067]FIG. 9 is a block diagram showing in detail the components and structure of an information application egg group in operative association with root server  304  of internal network  302 . With reference to FIG. 9, a registration server-root server represents the role played by root server  304 ; sub-root-community  1  and sub-root-community  2  represent the roles played by any two of information public sub-root servers  312 ,  314 , and  316 ; and sub-root-community  3  represents the role played by information private sub-root server  354 . An information application egg group is composed of two parts, which are indicated by the horizontal line dividing into two portions each of information application egg groups  356 ,  358 , and  360  in FIG. 8. The client part of an exemplary information application egg group  400  includes as its components a client user computer  402 , such as a PC and a local users profile  404  on a file system  406 . The ability to share files is a user right, and profile  404  records the identifications of local users authorized by the client user. File system  406  stores files downloaded from target community servers. The server part of information application egg group  400  includes as its components site server  200 ; parser manager  202  and its associated parsers  210 ,  212 ,  214 , and  216 ; data store  204  and its associated accessor  206 ; and database  208 . This server component configuration is the same as that presented in FIG. 6; therefore, for purposes of clarity, the same reference numerals are used to indicate common components in FIGS. 6 and 9. In a preferred embodiment, the functions of the client and server parts are combined so that they reside on the same platform.  
         [0068]    In accordance with the invention, for information application egg group  400 , a search by a client user causes a search query to reach community site server  200 , which is included in the search process and produces a file from data store  204  for delivery to the client user.  
         [0069]    One problematic issue arises in a P2P network, such as that established by any of P2P communication links  362 ,  364 , and  366 , stems from the fact that content can reside at any peer server on the P2P network. These servers lack specific knowledge of other peer servers on the network, other than a reference server that functions as the authoritative source of network information (i.e., a directory service). To prevent unauthorized peer clients from searching peer servers on the P2P network, the invention implements a method that indicates to a peer server that a peer client requesting a search is allowed to do so.  
         [0070]    The method is carried out by operation of registration server-root server  304  of FIG. 9, which is a central server known to all clients and used as a repository for public keys within the P2P network. When joining the P2P network for the first time, a client passes to registration server-root server  304  a public key portion of client-generated public/private key pair, together with an e-mail address and other information as required by a network administrator. The client is identified as one of the information application egg groups in FIGS. 8 and 9. The client at that time obtains the public key identifying registration server-root server  304  and stores its public key for future reference. The registration connection process is indicated by the arrow-tipped broken line between sub-root-community  1  server and site server  200  and the solid line connecting sub-root community  1  server and registration server-root server  304  in FIG. 9.  
         [0071]    [0071]FIG. 10 is a flow diagram of the session authentication and security process carried out in a P2P network. Each of sub-root community  1 - 3  servers of FIG. 9 replicates the authorization functions of registration server-root server  304 . Thus, these community servers store the public keys of client users of the P2P network. With reference to FIG. 10, the next time after registration, the client establishes communication with the sub-root community  1  server to request a challenge bit string. Sub-root community  1  server generates in response a random bit string and sends it to the client as a challenge bit string. The client then encrypts the challenge bit string using the client&#39;s private key and returns the encrypted challenge bit string to sub-root community  1  server. Sub-root community  1  server then decrypts the challenge bit string returned by the client using the public key sub-root community  1  server has on file for the client and compares the results of the decryption to the original challenge bit string. For successful verification, the result of decryption of the challenge bit string with the public key matches the original challenge bit string thereby, providing the identity of the client.  
         [0072]    Once the client&#39;s identity has been established, sub-root community  1  server returns to the client an access token that allows the client to query other peer servers in the P2P network. This access token includes, for example, the IP address reported by the client during the challenge/response and a time stamp from sub-root community  1  server. The access token is then signed using the private key of sub-root community  1  server.  
         [0073]    When it wishes to search a target peer server for information, the client passes the access token along with the query request packet. The target peer server  200  that receives the request then validates the access token. The validation process can take one of two forms. Since it knows the public key of the sub-root community  1  server, target peer server  200  can itself validate the access token. Alternatively, the access token can be passed to the sub-root community  1  server and validated there. If the time stamp is used to create an access token with a limited lifetime, checking back with sub-root community  1  server would eliminate any problems with time zones. A determination of a valid access token results in delivery of a download data request accompanied by the access token to target peer server  200 , which in response downloads data to client  402 .  
         [0074]    Proof of client identity is undertaken at the start of any session with a remote system, so that if a search is performed during a session that is different from a file transfer session, the access token would be resent and reverified when the file transfer session is started.  
         [0075]    To demonstrate additional capability of distributed information network  300 , FIG. 9 shows with an arrow-tipped broken line a community query connection between client  402  and private sub-root community  3  server to illustrate the ability of client  402  to search a private community server. An authentication process is undertaken to open a session with a private community server.  
         [0076]    Another problematic issue arises in connection with a distributed environment in which files or other information is shared. Because the share permissions preferably reside at the data source, security risks stem from a potential attacker wishing to share unapproved content and having physical access to the computer containing the data and share information. This situation allows for two classes of attack. The first class is the replacement of the data source itself. This is most easily accomplished by overwriting a shared file with an unapproved file. The second class of attack is modification of the share information, which typically will reside in a database. Altering these data can allow the data to point to an unapproved file rather than to the approved content.  
         [0077]    [0077]FIG. 11 is a flow diagram outlining the five steps of a process for providing file sharing security in a P2P network. With reference to FIG. 11, sub-root community  1  server functioning as an administrator has, as described with reference to FIG. 10, approval authority for content and is identified by a public/private key pair. The public key portion of this key pair is distributed to all peer node servers on the P2P network.  
         [0078]    An event when a user wishes to share content represents step 1 of the process. Information about such content (shown as row 1 information of the share server file table) including the name of the file, the size of the file, and the hash of the file is sent to the sub-root community  1  (authorizing) server. (A “hash” is formed by a cryptographic algorithm, is a condensed representation of the contents of a file.) The sub-root community  1  server examines the file to ensure the content is appropriate.  
         [0079]    Step 2 entails use by sub-root community  1  server of the row 1 information to access the file remotely. Step 3 entails approval of the file by sub-root community  1  server, which hashes the file name, file size, and file hash. When it approves the file for sharing, the sub-root community  1  server, using its private key, signs the information that was sent to it. Step 4 represents that the signature, together with the shared content, is stored in the file table on the share server.  
         [0080]    Step 5 represents when a share server receives a request for download of a file of shared information to a peer server. The share server in response retrieves the file name, obtains the file size from the file system, and computes the file hash. These three values are then hashed and compared against the decrypted signed hash returned from sub-root community  1  server. If any of these values do not match, the file is not made available to the peer server requesting the download. Otherwise, the file is made available to the peer server.  
         [0081]    Although it is described with reference to a P2P network, the file sharing security process can be implemented in any network in which a server can achieve controlled access to a file residing on a remotely located server.  
         [0082]    It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments of this invention without departing from the underlying principles thereof. As a first example, the functions of a client (e.g., client applet) and a root server can be combined so that they reside on the same platform. As a second example, an applet, an application, a network browser, or other type of operating system client can be used to initiate a topic query or search. The scope of the invention should, therefore, be determined only by the following claims.