Method and apparatus for effecting secure document format conversion

• US 6,470,086 B1
• Filed: 11/17/2000
• Issued: 10/22/2002
• Est. Priority Date: 07/23/1998
• Status: Expired due to Term

• Current Assignee: Tumbleweed Communications Corporation (Axway Software SA)
• Original Assignee: Tumbleweed Communications Corporation (Axway Software SA)
• Inventors: Smith, Jeffrey C.
• Primary Examiner(s): Smithers, Matthew
• Application Number:
  US09/715,940
• Time in Patent Office: 704 Days
• Field of Search: 713/153, 713/164, 713/165, 713/166, 713/167, 380/255
• US Class Current: 380/255
• CPC Class Codes: G06F 21/606 by securing the transmission between two devices or processes
• CPC Class Codes: G06F 2211/008 Public Key, Asymmetric Key, Asymmetric Encryption
• CPC Class Codes: H04L 63/02 for separating internal from external traffic, e.g. firewalls
• CPC Class Codes: H04L 63/029 Firewall traversal, e.g. tunnelling or, creating pinholes
• CPC Class Codes: H04L 63/0442 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption cryptographic mechanisms or cryptographic arrangements for public-key encryption H04L9/30
• CPC Class Codes: H04L 63/0464 using hop-by-hop encryption, i.e. wherein an intermediate entity decrypts the information and re-encrypts it before forwarding it
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/565 Conversion or adaptation of application format or content adding application control or application functional data H04L67/561
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]

Abstract

A method and apparatus is provided for effecting secure document delivery in any of various document formats. A document is encrypted with the public key of a server associated with the recipient of the document, instead of with the public key of the intended recipient. The receiving server is located within a firewall. The encrypted document is forwarded to the server within the firewall. The server decrypts the document using its corresponding private key, converts the document to a now data representation, and then either forwards the document to the recipient inside the firewall, or re-encrypts the document with the public key of an intended recipient outside of the firewall or with the public key of another server that is associated with the intended recipient of the document.

Claims

1. A method for effecting secure document delivery in any of a plurality of document formats, comprising the steps of:

encrypting said document with a public key of a server associated with a recipient of the document, wherein said server is located within a firewall;

forwarding said encrypted document to said server within said firewall;

decrypting said document with said server using said server'"'"'s corresponding private key;

converting said document to a new data representation;

forwarding said document to said recipient;

sending a high level representation of said document to said recipient via said server, wherein said server comprises a dynamic document conversion server;

deferring a decision to descend to a lower level representation;

determining a most appropriate level of representation for said document based upon said recipient'"'"'s capability to reproduce said document; and

completing delivery of said document to said recipient.

2. A method for effecting secure document delivery in any of a plurality of document formats, comprising the steps of:

encrypting said document;

forwarding said encrypted document to a server within said firewall;

decrypting said document with said server;

converting said document to a new data representation;

forwarding said document to a recipient;

sending a high level representation of said document to said recipient via said server, wherein said server comprises a dynamic document conversion server;

deferring a decision to descend to a lower level representation;

determining a most appropriate level of representation for said document based upon said recipient'"'"'s capability to reproduce said document;

converting said document to a lower level representation as appropriate and necessary for said recipient'"'"'s capability to reproduce said document; and

completing delivery of said document to said recipient.

3. An apparatus for effecting secure document delivery in any of a plurality of document formats, comprising:

means for encrypting said document with a public key of a server associated with a recipient of the document, wherein said server is located within a firewall;

means for forwarding said encrypted document to said server within said firewall;

means for decrypting said document with said server using server'"'"'s corresponding private key;

means for converting said document to a new data representation;

means for forwarding said document to said recipient;

means for sending a high level representation of said document to said recipient via said server, wherein said server comprises a dynamic document conversion server;

means for deferring a decision to descend to a lower level representation;

means for determining a most appropriate level of representation for said document based upon said recipient'"'"'s capability to reproduce said document;

means for converting said document to a lower level representation as appropriate and necessary for said recipient'"'"'s capability to reproduce said document; and

means for completing delivery of said document to said recipient.

4. An apparatus for effecting secure document delivery in any of a plurality of document formats, comprising:

means for encrypting said document;

means for forwarding said encrypted document to a server within said firewall;

means for decrypting said document with said server;

means for converting said document to a new data representation;

means for forwarding said document to a recipient;

means for sending a high level representation of said document to said recipient via said server, wherein said server comprises a dynamic document conversion server;

means for deferring a decision to descend to a lower level representation;

means for determining a most appropriate level of representation for said document based upon said recipient'"'"'s capability to produce said document;

means for converting said document to a lower level representation as appropriate and necessary for said recipient'"'"'s capability to reproduce said document; and

means for completing delivery of said document to said recipient.