TH79434A - Multiple encryption points to a single document for exclusive use. - Google Patents

Abstract

DC60 (24/07/44) Methods and systems for selecting the encryption and decryption of sections of a document that provide different levels of access using different encryption keys. A document may be encrypted at different levels of document sections ("section" here is used in a general sense), and different sets of encryption keys will be used for encryption of each section. User A, with access level 1, may only have access to the sections encrypted with access level 1 plus the unencrypted sections. An example of the use of this technique is in a hospital. Each patient's record may be organized into sections to be encrypted separately, allocating access to only the sections that are necessary for nurses, while simultaneously allocating broader access to the records for doctors. Nurses may receive personal encryption keys that determine their level of access to the sections of the document according to their rights. There may also be levels that are only accessible to male nurses or healthcare providers, using only a small area of the kitchen. Methods and systems for selecting the encryption and decryption of sections of a document that provide different levels of access using different encryption keys. A document may be encrypted at different levels of document sections ("section" here is used in a general sense), and different sets of encryption keys will be used for encryption of each section. Different levels of encryption are used for different sections of a document ("section" here is used in a general sense), and different sets of encryption keys are used for encryption for each section. User A, with access level 1, may only have access to the sections encrypted with access level 1, plus any unencrypted sections. An example of this technique's application is in a hospital; individual patient records might be organized into sections, each encrypted separately to allocate access to only the sections necessary for nurses, while simultaneously granting broader access to doctors. Nurses might receive individual encryption keys defining their access levels to specific sections of the document according to their rights. There might even be sections restricted to male nurses or healthcare providers, with limited access even to a small area like a kitchen.

Claims (23)

1. A method for securely sending the first set of documents which consists of the following steps: creating the first and second level encryption keys; encrypting the first part (130) of such first set of documents with the encryption key of such first level document and encrypting the first and second parts (135) of such first set of documents with the encryption key of such second level document; creating a second set of documents (220) or part (520) of such documents in which such second set of documents or parts are encrypted with the encryption keys of such first and second level documents; and sending such first set of documents or such first or second set of documents as appropriate to the point of choice in the steps of creating the transmission method. 2. The method specified in Claim 1, where the encryption key of the first or second level document is symmetrical. 3. The method set forth in Claim 1, which involves obtaining at least two sets of public key encrypted from the recipient, shall, in such a manner, encrypt the second set of such document in such a way that the corresponding sets of the first and second level document key are available for decryption by using the first set of at least two such public key encrypted, and in such a way that the other corresponding sets of the first and second level document key are available for decryption by using the second set of at least two such public key encrypted. 4. The method specified in Claim 3, where such procedure of encryption shall include the encryption of at least the first public key of the two public key sets as stated in Part One of the Document, Part Two of the Document, or Part One of the Document, and the encryption of at least the first and second public key of the two public key sets as stated in Part Two of the Document, Part Two of the Document, or Part One of the Document. 5. The method specified in claim paragraph 3, whereby the encryption keys of the first and second level documents are symmetrical. 6. The method as specified in Claim 1, whereby the procedure of transmission shall include encrypting such first document, or such first or second document as appropriate, to a point chosen in the procedure of creating the transmission. 7. The method of document encryption consists of three steps: encrypting the first part of the document using the first key, encrypting the second part of the document using the second key, and encrypting the result of the first and second encryption steps using a third key, which is the recipient's public key. 8. The method of encrypting the document as specified in claim 7, whereby the first key is the first public key of said recipient and the second key is the second public key of said recipient. 9. The method of encrypting the document as specified in claim 7, where such first key is the first symmetric key and such second key is the second symmetric key, and the method shall include the procedure of encrypting such first symmetric key with the public key. 10. The method specified in Claim 9, in which the second part shall include a portion of the first part, and that part shall be encrypted with the first symmetric key. 11. The method of encrypting the document as specified in claim 9, which consists of the procedure of encrypting the aforementioned second public key with the second public key. 12. A method for securely providing access to the first and second readers of a document, consisting of the following steps: sending to the sender of the document a public key matching the reader's public key, which is then used to encrypt the document; receiving the encrypted data from the sender; decrypting a portion of the encrypted data using a private key matching one of the public keys; and using the result of the first decryption step to access a portion of the data corresponding to one of the public keys. This involves decrypting another portion of the encrypted data using a private key matching another public key, and finally, using the result of the second decryption step to access a portion of the data corresponding to the third public key. 13. The method specified in Claim 12, whereby the first and second steps of each decryption step shall include decrypting any portion of such data to unlock the various sets of encryption keys. 14. The method specified in Claim 12, whereby the first and second steps of decryption shall include the use of such sets of encryption keys to unlock at least one portion of the encrypted data in order to provide access to a specific portion of such document. 15. The method specified in Claim 12, where the first and second steps of decryption shall subsequently involve the use of such set of encryption keys to unlock at least one portion of the encrypted data, in order to provide access to the document. 16. A data file (95+220) containing an encrypted document (95,595) with a key portion (520) and an encrypted document portion (585), such key portion which at least some parts can be decrypted by the first public key to provide access to the first symmetric key, such key portion which at least some parts can be decrypted by the second public key to provide access to the second symmetric key, the first part (210) of such encrypted document portion which can be decrypted by the first symmetric key and the second part (215) of such encrypted document portion which can be decrypted by the second symmetric key. 17. A data file containing an encrypted document (95) and at least two sets of encryption keys, such encryption keys are encrypted in such a way that they are accessible by at least two public keys and in such a way that the first part (130) of such encrypted document is accessible by decryption by the first subset of such encryption keys and such first subset is decryptable by at least two public keys and in such a way that the second part of such encrypted document is accessible by decryption by the second subset of such encryption keys and such second subset is decryptable by at least two public keys. 18. A data set stored on a storage medium consisting of a document encrypted in sections using different sets of encryption keys; the first part of the document is encrypted with the first key of a sequence of such keys; the second part of the document is encrypted with the second key of a sequence of such keys; the first and second consecutive keys are encrypted in a file in such a way that the first key can be decrypted by the first public key and the second key by the second private key. 19. A set of data stored on a storage medium consisting of encrypted documents in various sections, encrypted using different sets of keys; the first section of such document, which is encrypted with the first and second consecutive keys; the second section of such document, which is encrypted with the first consecutive key; the first and second consecutive keys, which are encrypted in a file so that the first and second keys can be decrypted using the first private key, and the first key can be decrypted using the second private key. 20. A document decryption program stored on a storage medium contains codes that define the process for decrypting specific parts of the data set using various keys. These codes then yield subsequent sets of keys. Under the decryption process, the codes determine the next steps that can be extracted from the data set of the document matching the corresponding sets of keys, providing access to the specific section of the document that matches those keys. 21. The program stored as specified in Claim 20, where the aforementioned cryptographic keys are public keys. 22. The program stored as specified in claim clause 20, where each set of such keys shall be valid only for the said document. 23. The program stored as specified in Claim 20, where each such set of subsequent cryptographic keys is a symmetrical cryptographic key.