Twitter
`Ex. 1020
`IPR1 of U.S. Pat. No. 6,895,557
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`Description
`
`EP0338774A2
`
`The invention relates to thefield of computer networks. More particularly. the invention relates to techniques for the
`delivery of electronic documents to users over the Internet.
`The development of computerized information sources. such as those provided through the Internet or other on-
`line sources, has led to a proliferation of electronically available information. Currently, a user who subscribes to the
`Internet manually navigates through the Internet to visit sites which may or may not be of interest.
`An inherent problem in this Internet system is that the available information is distributed through a "pull" type infra
`structure. where the user who wants to receive information must manually search sites of interest. or use a finder appli-
`cation. to search and download appropriate information. For a user who wishes to publish and distribute information or
`documents, either an individual or a larger entity that has information that is desired to be distributed. the present "pull"
`system doesn‘t allow the freedom to send and distribute to a recipient or group of recipients, in a "push" fashion.
`Facsimile technology is widely used at the present time for the distribution of simple documents. but has numerous
`drawbacks. including lower quality primed documents. costly and bulky paper copies (particularly if the recipient doesn't
`care to have a paper copy}. loss of content (e.g. text and graphics can't be edited or manipulated). and time require-
`ments for transmission, particularly for long or complex documents.
`Electronic Mail (Email) provides a means for sending electronic messages from computer user to another. E-mail
`has advantages of convenience. format and storage of messages for later retrieval. As such. Email has been accepted
`and widely used for basic communication. E-mail is typically an ASCII based format. however, and proves to be very
`limiting for the communication of long or formatted documents. As well. E-mail is not the medium of choice for the dis-
`tribution of complex documents. such as reports. articles. advertisements and art which can include page layout grids.
`postscript-formatted objects. multiple fonts with tracking and kerning, graphics. Embedded tables and spreadsheets, and
`other complicated information. Some E—mail systems provide a means for appending an ASCII based E-mail message
`with an associated file. to be downloaded along with the E-maii message. Most systems that allow the appending of an
`associated file are designed to allow a single user to send unsecured files to an associate or friend. and neither allow
`for controlled automated distribution to multiple recipients. nor do they provide advanced accounting. billing or other
`such features (e.g.. receipt notification). E-mail gateways also limit the applicability of attachments, and do not solve the
`problems of security and receipt notation or acknowledgment.
`C. Baudoin. lnterenterprise Electronic Mair‘ Hub, US. Patent No. 5.406.557 (11 April 1995) discloses an interenter-
`prise communications center. which has a computer hub comprising a common core and a plurality of input and output
`modules. The input modules connect to a first end user. and convert a message sent by the first end user into a univer-
`sal format. The hub core queues the message and forwards it to the output module for conversion into the format of the
`destination user. While the disclosed hub discloses techniques to relay simple e-mail messages. it is designed to con-
`vert the e-mail message formats. thus losing the integrity of the original text-based file.
`The disclosed prior art systems and methodologies thus provide scrne methods for the delivery of documents. but
`fail to provide an economical. fast document delivery system that operates in a push-fashion. while conserving the
`integrity of the original electronic file. The development of such an electronic document delivery system would constitute
`a major technological advance. In addition, the ability to distribute electronic portable high-quality documents to many
`recipients in a controlled. economical and accountable fashion would constitute a further technological advance.
`The Internet is increasingly being used for communications. It is now possible on the Internet for a sender to direct
`a document to a specific recipiem. regardless of platform. operating system. or email system. Such communication is
`possible even when the recipient is not a computer but. rather. a fax machine or printer connected to the Internet.
`In many instances, the sender of a document will reside on a local area network, referred to as an intranet. The
`sender's computer may be connected to the Internet directly, or through the intranets server. An intranet is frequently
`protected and insulated from the Internet by a firewall or proxy server. Atirewall is software andror hardware which limits
`access to an intranet or a desktop computer. A proxy server is dedicated software andlor hardware which intercepts
`requests between machines running inside an intranet and machines outside the intranet.
`Such firewall provides one or more of a few basic services. l-'rrst. a firewall prevents intranet users from accessing
`specific information on the Internet. Thus. an office worker is restricted from accessing non-work-related Internet sites.
`Second, a firewall restricts outside access to the information available on the intranet. Third. a firewall prevents intranet
`users from sending confidential information from the intranet to the Internet. Typically, blocking unsolicited outside
`access to the intranet also blocks information transfer from intranet to Internet.
`
`Various methods have been used to transfer data on the Internet between intranets protected by firewalls. One
`such method is the key management scheme described in Aziz. Method and Apparatus for Key-Management Scheme
`for Use with Internet Protocols at Site Firewalls, US. Patent No. 5.416.642 (16 May 1995). In this method. intersite traf-
`fic is encrypted at the Internet Protocol (IP} layer by using a Skip scheme to prevent detection of a source and destina~
`tion address of a communicating node.
`IP packets are encrypted only from site firewall to site firewall. such that only firewall servers need to participate in
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`the Skip scheme. When a firewail receives from an interior site node an IP packet intended for a remote firewall.
`encrypts the IF‘ packet and sends it encapsulated in another IP packet destined for the remote firewall. The remote fire-
`wall decrypts the encapsulated packet and sends it in the clear to the destination node on the interior side of the remote
`firewall.
`
`Such method. however. requires the encrypted lP packet to be received by a remote firewall sewer that is config-
`ured to decrypt the packet. The encrypted information cannot be directly sent to a computer or intranet system that
`does not use such firewall server. or to a device such as a fax machine or printer.
`A security system for connecting computer networks is described in Geib. Security System for Preventing Unau-
`thorized Ccmmunications Between Networks by Translating Communications Received in IP Protocol to Non-IP Proto-
`col to Remove Address and Routing Services Information. US. Patent No. 5,550,984 (27 August 1996). However. Geib
`does not address how documents may be sent through a firewall or proxy server.
`It would therefore be an advantage to provide a method and system for sending documents through a series of fire-
`walls andior proxy servers. It would be a further advantage if such method and system permitted the documents to be
`transmitted to a device such as a fax machine or a printer. It would be yet another advantage if such method and system
`did not require the receiving computer of device to be served by a decrypting firewall.
`One of the many complexities associated with delivering information between two disparate systems stems from
`basic incompatibilities between those systems including. for exarrple. differences in capabilities. A printer has a very
`different set of capabilities than a personal computer. and a commensurate set of data formats which the printer might
`accept. A personal computer. for example. might be capable of processing a WordPeriect document. a portable docu-
`ment (e.g. Adobe Acrobat or Novetl Envoy). or an HTML document. A printer. by contrast. might only be capable of
`accepting a PCLfite or a Postscript file. A fax machine, as with a printer. may only accept a Grotp 3 compressed black
`and white raster representation of a document. Thus. various devices have various capabilities in terms of the types of
`data they may accept.
`Similarly. different data types offer different levels of flexibility and function. For example, an Envoy or PDF file can
`be scated to any resolution. can support millions of colors. and can include text and fonts. A Group 3 compressed fax
`image. on the other hand. is limited in resolution. only supports black and white colors. and includes no text or fonts.
`thereby limiting the ability of a recipient of a Group 3 compressed image to perform any operations. except for rudimen-
`tary operations.
`The extended flexibility of a more robust data representation. such as a portabte document. enables such docu-
`ments to be converted to less robust representations. By illustration. a portabte document might be converted to a Post-
`script file or even a Group 3 compressed image. One might therefore suggest that a portable document is a high level
`data representation and a Group 3 compressed image is a low level data representation.
`In most cases, it the recipient system is capable of receiving a high level data representation. such representation
`is the data representation of choice due to the increased capabilities such representation provides. Thus. such repre-
`sentation offers a preferred common format. especially if such representation includes a mechanism that can convert
`the high level representation to a lower level representation as necessary.
`M. Williams. Ft. Yun. Method and Apparatus For Enhanced Electronic Mail Distribution. US. Patent No. 5.424.724
`(13 June 1995) disclose a method and apparatus for enhanced electronic mail distribution which permits distribution of
`electronic mail documents to multiple host systems andior external networks via a single host agent. A host agent ref-
`erence table is established at selected host agents within a local network Each host agent reference table includes an
`identification of selected destination nodes associated with an identified host agent for those nodes. A referral to the
`host agent reference table is used to determine the appropriate host agent for an electronic document destined for a
`selected node. No provision is made within this method and apparatus for dynamic data conversion. Thus. documents
`are delivered with its level of representation unaltered and without regard for processing capability at a destination
`node.
`
`T. Schultz. A. Gross. B. Pappas. G. Shifrin. L. Mack. Apparatus and Method of Distributing Documents To Ftemote
`Terminais with Different Formats. US. Patent No. 4.754.428 (28 June 1988) and T. Schultz. A. Gross. B. Pappas. G.
`Shitrin. L. Mack. Electronic Matt. U.S. Patent No. 4,713,780 (15 December 1987) disclose a method and apparatus for
`delivering a document originated at a local site by a source having a printer output that is normally connected to a
`printer. to one or more remote locations having printers or display devices that may differ from the printer normally con-
`nected tc the printer output of the document generating source. Printer command signals which are normally provided
`at the printer output are converted to character and position data which represent the respective characters and their
`horizontal and vertical positions on each page of the document. The character and position data are transmitted to a
`remote location and reconverted to a form for driving a printer or other display device to produce a line-for-line conform-
`ing copy of the original.
`The '428 and 780 patents disclose the use of upstream data conversion. but do not provide downstream data con-
`version. That is. the '428 and 780 patents disclose a method and apparatus that allows text to be sent to a primer and
`converted to a primer specific format. However. such method and apparatus lacks the ability to start with a high-level
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`representation of the data. and only convert to a lower level representation if such conversion is determined to be nec-
`essary. Thus. such approach is not satisfactory where printer format is not known or established prior to document orig-
`ination. or where a heterogeneous network. such as the Internet. is used to deliver data.
`
`L. Harkins. K. Hayward. T. Herceg. J. Levine. D. Parsons. Network Having Seiectiveiy Accessibie Recipient Priori-
`tized Cornmunication Channei Profiies. US. Patent No. 5.513.126 (30 April 1996) discloses a method for a sender to
`automatically distribute information to a receiver on a network using devices and communications channels defined in
`a receiver profile. The receiver profile establishes the properties and mode for receipt of information for receivers on the
`network and the profile is published in a network repository for all network users or is accessible for selected groups or
`individuals on the network. The disclosed network does not provide for data conversion. but rather involves sending pre-
`determined data based on the capabilities of the recipient which are communicated through channels. Thus. each
`recipient must first establish a format before data are exchanged.
`M. Bloomfield, Sender—Baseo’ Facsimiie Store and Forward Faciiity. l.S. Patent No. 5.404.231 (4 April 1995) dis-
`closes a system that provides sender-based store and forward services for delivering facsimile based information. The
`system is solely concerned with the delivery of facsimile bitmap images. and not with data conversion.
`In view of the limitations attendant with the state of the art. it would be advantageous to provide a system in which
`the ability to descend to a lower level representation is preserved to allow the flexibility to do so at a future point in time.
`but that also enables a richer set of functions as appropriate.
`The present invention intends to overcome the above problems. The object is solved by the apparatus according to
`independent claims 1, 13 and 35. the method according to independent claims 7. 15. 57 and 66 and the system of
`binary data delivery according to independent claim 69.
`Further advantages. features. aspects and details of the invention are evident from the dependent claims. the
`description and the accompanying drawings. The claims are intended to be understood as a first, non-limiting.
`approach of defining the invention in general terms.
`The present invention generally relates to the field of computer networks. in particular it relates to techniques tor
`the delivery of electronic document to users over the internet.
`It is an object of the invention to provide an electronic document delivery system and methods of its use.
`A document, preferably in a portable format, is fonivarded to a remote server {e.g. using HTTP to "push" the docu-
`ment to the server). The server sends a generic notification of the document to an intended recipient. and the recipient
`can download the document from the server using local protocols. In preferred embodiments. the invention is used tor
`the controlled delivery of portable documents. from a sender to a large number of recipients. using a network of servers
`that route the documents and notifications in a store and fonivard manner. while providing routing and accounting infor-
`mation back to the sender.
`
`According to a further aspect. the invention also provides a method and system for sending documents from a
`desktop computer inside an intranet through a series of firewalls andior proxy servers to a server residing on the Inter-
`net. Firewalls presume that HTTP for textual data is a valid operation that allows users to fill in HTML forms. Thus. fire-
`walls do not block H'l'l'P for textual data. The invention circumvents the security provided by firewalls by using this
`Ifeature of HTTP to move a document through the firewall.
`A computer in an intranet system protected by a firewall or proxy server uses a software application to access the
`Internet. The software also encodes binary data to be sent as text. This binary data may be subdivided into smaller text
`packets. The text packets are sent. using HTTP. to a server outside the firewall. which has been configured to accept
`such text packets. The server converts the text packets back to the original binary data representation. The binary data.
`once resident on the imernet server. can then be forwarded directly to other internet servers, internet desktop comput-
`ers, printers. or fax machines.
`The invention provides in a further aspect a documem delivery server which dynamically customizes the format of
`a document to be delivered. based on the capabilities of the recipient and the type of document to be delivered. The
`server thereby enables the transparent delivery of formatted documents. regardless of the capabilities of the recipient.
`For example. the recipient platform could be a desktop computer. a network computer. a primer. a fax machine. or a
`personal digital assistant. The server atlernpts to maintain the information contained in the document in a high level rep-
`resentation and defers the decision of when to convert to a lower level representation. thereby maximizing the potential
`set of options and function at each step in the delivery process. Accordingiy. the invention starts with a high-level rep-
`resentation of data. and only converts to a lower level representation if necessary.
`According to still another aspect a method and apparatus is provided in which a document preferably in a portable
`format. is fonivarded to a remote server (e. g. using H'l'l'P to "push" the document to the server). The server sends a
`generic notification of the document to an intended recipient. and the recipient can download the document from the
`server using local protocols.
`A method and system is also provided that sends documents trom a desktop computer inside an intranet through
`a series offirewalls andior proxy servers to a server residing on the Internet. A computer in an intranet system protected
`by a firewall or proxy server uses a software application to access the Internet. The software also encodes binary data
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`to be sent as text. This binary data may be subdivided into smaller text packets. The text packets are sent. using H'l'l'P,
`to a server outside the firewall, which has been configured to accept such text packets. The server converts the text
`packets back to the original binary data representation. The binary data. once resident on the internet server. can then
`be forwarded directly to other internet servers. internet desktop computers. printers. or tax machines.
`
`A document delivery server is also provided that dynamically customizes the tormat of a document to be delivered,
`based on the capabilities ot the recipient and the type of document to be delivered. The server attempts to maintain the
`information contained in the document in a high level representation and defers the decision ot when to convert to a
`lower level representation. thereby maximizing the potential set of options and tunction at each step in the delivery proc-
`ess.
`
`The invention will be better understood by reference to the following description ot embodiments of the invention
`taken in ooniection with the accompanying drawings, wherein:
`
`Figure 1 is a block diagram which depicts a binary file delivery system using one binary file server:
`
`Figure 2 is a block diagram which depicts a binary file delivery system using two binary file servers;
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`Figure 3 is a block diagram which illustrates key elements of a store item;
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`Figure 4 is a schematic depiction oi the binary tile delivery server;
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`Figure 5 provides an example of the architecture of one embodiment of the binary file server;
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`Figure 6 illustrates different types of store events errployed by the binary file delivery server;
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`Figure 7 is a block diagram of the specific components within the binary file delivery server architecture;
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`Figure 8 provides a block diagram illustrating of the architecture of the store;
`
`Figure 9 illustrates how the user session organizes internet clients into three layers. including sessions, transac-
`tions. and transports;
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`Figure 10 illustrates the non-interactive tasks of a delivery. once the send session has created a store item or
`another server is forwarding a store item;
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`Figure 1 1 provides details of the account manager architecture;
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`Figure 12 provides details of the logger architecture;
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`Figure 13 provides details of the server connector architecture;
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`Figure 14 provides a functional block diagram which depicts a ponable document delivery system using one port-
`abte document delivery server;
`
`Figure 15 provides a tonctional block diagram which depicts a portable document delivery system using two port-
`abie document delivery servers:
`
`Figure 16 illustrates how a portable document send client application and a ponable document receive client appli-
`cation are used in the invention;
`
`Figure 17 illustrates how a server configuration user interface apptication is used in the invention;
`
`Figure 18 illustrates how a document can be sent by the fax gateway of a server to a printer;
`
`Figure 19 illustrates how a document can be sent by the department gateway of a dedicated corporate server
`through a LAN to a department primer;
`
`Fig. 20 is a schematic diagram of the system for transmission of data across a ‘lirewalt andtor proxy server, accord-
`ing to the invention;
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`Fig. 21 an exemplary flow chart illustrating the algorithm for transmission ot data across a firewall andlor proxy
`server, according to the invention;
`
`Fig. 22 is an exemplary flow chart of the set of operations necessary to transfer a native tile across a firewall and.-‘or
`proxy server, according to the invention;
`
`Fig. 23 is a block schematic diagram that shows an example of an application involving a dynamic document con-
`version server according to the invemion;
`
`Fig. 24 is a block schematic diagram that shows another example of an application involving the dynamic document
`conversion server according to the invention; and
`
`Fig. 25 is a block schematic diagram showing a presently preferred implementation ot the dynamic data conversion
`server according to the invention.
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`The binary file delivery system 10 enables corporations, pubiishers and individuals to distribute documents elec-
`tronically. importantly. unlike existing Web based document publishing technologies, the binary tile delivery system 10
`allows the directed and secure distribution of documents. The Web couid currently be characterized as a pull—publishing
`environment. where the consumer of documents must find and retrieve documents from a server. Push-publishing. by
`contrast. allows the producer ot a document to direct the delivery of documents to consumers. Facsimile (tax). the
`postal service, and eiectronic mail (E-mail) are all examples of push—pub|ishing.
`Figure 1 is a block diagram which depicts a binarytile delivery system 10 using one binary file server 12. The binary
`tile delivery system 10 allows users to push documents, enabling the producer of documems to direct where those doc-
`uments will go. One way that the binary file delivery system 10 achieves push-publishing is by combining HTTP. which
`is usualty implemented to pull information over a network. with SMTP (which only supports text). Additionally. the binary
`file delivery system 10 provides a host of services to facilitate the various applications of directed document delivery. At
`one level. the binary file delivery system 10 can be characterized as a new generation of facsimile technology, which
`utiiizes networks instead of telephone lines, and moreover. introduces support for new document representations vastly
`superior to existing fax formats. At another level. the binary file delivery system 10 is a general purpose document deliv-
`ery server capable 01 supporting massive amounts of documents and transactions. In all cases. the binary tile delivery
`server 10 provides a complete and robust solution for document delivery.
`The binary file delivery server 10 is used for sending a set ot binary files from one end-point to one or multiple end-
`points. An endpoint is typicalty a recipient 22 with Internet access. but can also be another emity. such as a facsimile
`machine 172 or a printer 178 (Figs. 14. 15). The delivery of binary files is accomplished in a reliable, accountable. and
`tractable manner. The binaryfile delivery system 10 provides several levels of security tor the directed files. from E-mail
`equivalent security. to better than facsimile or physical mail. The system also provides user account management
`including the credit and debit oi billing accounts. The system can also cooperate between multiple binary file delivery
`servers 12. which may or may not be controlled by some other authority. Figure 2 depicts a binary file delivery system
`using two binary file servers 12a and 12n. which communicate across an Internet.
`The binary tile delivery server 12 operates in three primary modes. which include a public mode. where senders 16
`set up their accounts 132 themselves and are subject to billing. a private mode. where senders 16 are controlled by an
`administrator, and billing is more an internal accounting issue than a collection issue. and a publishing mode. where
`there are many recipients 22. but tew senders 16.
`The binary file delivery server 12 is comprised of separate functional components, and are not necessarily proc-
`esses or shared libraries. The binary file delivery server 12. shown schematically in Figure 4. includes an intelligent
`storage compartment called a store 42. which is augmented by a set of clients 44a -44n, called store clients 44, which
`use the store methods and listen to the store events, but do not imeract with or know about other clients 44. An account
`manager 46 component is a shared service that keeps information about the sender 16. The design also incorporates
`intcrmation about recipients 22 for the case of a receive application (as opposed to e-mail notification).
`The clientlserver general architecture provides a better extensibility than a more pipelined structure. It also decou-
`ples the store clients 44 from each other. which can be useful in the context where some tasks are interactive. while
`others are more background oriented.
`
`The Store.
`
`The store 42 contains a set of store items 48. As shown in Figure 3. a store item 48 includes a tree of binary files
`34 and a descriptor 36, which is a set of store-defined and client-defined attributes. The tree of binary files 34 can be
`viewed as part of the store-defined attributes.
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`The bile storage system provides the following functionality:
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`EP08~'38774A2
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`1) Permanent storage of Store items 48 (e.g. the binary file tree 34 contained in a store item 48 is written to disk)
`2) Client readfwrite access to the descriptor 36. which is made up of store-defined and client-detined attributes
`{eg. a client 44 can write the expiration date of a store item 48)
`3) Client notification of store events 67 (e. g. clients 44 can be notified of the creation event 68 of a new store item
`48)
`4) Internal management according to store defined attributes (e.g. store item expiration date generates an event).
`
`The store 42 provides access to the store items 48 and generates store events 67, wherein store items 48 have
`store-defined attributes such as ID. creation date. file count, file names. file data, and store events 67 can be listened
`
`to by the clients 44. Store events 67 may include the creation 68, deletion 69 or modification 70 of a store item 48. The
`events 67 play a crucial role in the architecture. since this defines how the clients 44 synchronize their work with a very
`limited knowledge of the other.
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`Eztctefitienta
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`Store clients 44 can be of a wide variety, and specific clients will be detailed further. In this framework, a store client
`44 is some component which uses some of the store methods and or listens to some of the store events 57 to perform
`useful tasks on the store items 48.
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`Amgum Manager.
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`The account manager 46 provides readtwrite access to user and billing accounts, and is used by clients 44 or other
`components of the system 10. The store 42 does not use or know about the accounts.
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`Other Compgnents.
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`Other components used by the store clients 44 and the store 42 itself are irrplemented within the architecture of
`the system. For example. inter-server communication. log management. and other administrative services. which is dis-
`cussed below.
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`Figure 5 provides an example of the architecture of one embodiment of the binary file server 42. including client 44
`modules (52-66) that are used to irrplement server functions. The Internet Send 52 is used to create store items 48 and
`fills in the attributes. The Internet Fteceive 54 opens existing store items 48 and can be used to modify their attributes.
`A Fax gateway 56 listens to the creation events 68 generated by the store 42. processes relevant store items 48. and
`then deletes them from the store 42. A fonivarder 58 listens to the creation events 68 generated by the store 42, and
`then examines the attributes of the new store items 48. and decides if fonivarcting is necessary. An archiver 60 listens
`to deletion events. and copies the store item 48 to secondary private storage before deletion occurs. The format trans-
`lator 62 listens to creation. examines attributes. and if translation is needed. it reads. processes and writes back the files
`in the store item 48. The web publisher 64 listens to the creation events 68 and checks if the store item attributes spec-
`ified a web publishing. and if so. read the attributes as necessary. A pickup notifier 66 listens for a creation event 68,
`and then notifies recipients 22.
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`Security Issues for Internet~based Users.
`
`While the Binary File Delivery System 10 offers theftexibility to support specialized security solutions. it readily sup-
`ports current industry-standard security solutions. including:
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`a) secure server interconnect and server authentication (availabte with SSL 2.0. which is built into the servers
`(HTTP);
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`b) secure Server-to-Server (on top of SSLX);
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`c) support end-points private key (the private key has to be exchanged by the users using their own channels.
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`d) support end-points ptblic key. using CryptoAP! or the standard user public key. The system can also help the
`user generate a public key for BFD-use only. and update user account information with it. so that the sender does
`not have to communicate directly with the recipient to get the public key; and
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`e) Ciient Authentication by the server with SSL and MS PCT (End user can get their own certificate and be authen-
`ticated by the servers).
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`An important aspect of the binary file delivery server 12 is that it handles multiple requests in parallel and minimizes
`the response time for most requests. Therefore, synchronization issues are important. for both correctness and system
`performance. Performance is enhanced by minimizing synchronized data access. deferring to asynchronous process-
`ing whenever possible. and by using multitasking and Inter-Process Communication (IPC) for the platform. One embod-
`iment of the server 12 relies heavily on threading, which provides low overhead multitasking within one process. and
`leverages multiprocessor capabilities when available. The IPC on this embodiment uses named pipes. in addition to
`mail slots or Ftemote Procedure Call (HPC).
`Figure 7 provides a block diagram of the specific components within the binary file delivery server 12 architecture.
`The user session 72 handtes send sessions. receive sessions (which are implemented when the user is using a
`BFD desktop application 192. 198). HTML receive sessions (which are implemented through an HTML browser. as
`opposed to when the user is using the BFD desktop 164 (note that a BFD desktop session may go through HTML)).
`maintenance sessions (which implement the account setup and maintenance sessions (e.g. notification downloads.
`account setting modifications (not to