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US7181017B1 Expired / Lapsed US ⏱️ 0.0 years remaining

System and method for secure three-party communications

Assignee: RPX Corp
•
Filing: 2002-03-25
•
Granted: 2007-02-20
•
Expires: 2022-03-25
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Abstract

Abstract A system and method for communicating information between a first party and a second party, comprising identifying desired information, negotiating, through an intermediary, a comprehension function for obscuring at least a portion of the information communicated between the first party and the second party, communicating the encrypted information to the second party, and decrypting the encrypted information using the negotiated comprehension function. Preferably, the intermediary does not itself possess sufficient information to decrypt the encrypted information, thus allowing use of an "untrusted" intermediary. The comprehension function may be dynamic with respect to its response to the negotiated comprehension function, and thus permit limitations on the use of the information by the second party. For example, the decryption of the encrypted information may be time limited.

Inventors

  • 👤 Robert H. Nagel
  • 👤 David P. Felsher
  • 👤 Steven M. Hoffberg

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 13:38
CPC Classifications
H; H04; H04L; H04L63/00; H04L63/04; H04L63/0428; H04L63/0442; H04L63/06; H04L63/061; H04L9/00; H04L9/08; H04L9/0816; H04L9/0819; H04L9/0825; H04L9/0838; H04L9/0841; H04L9/30; H04L9/3006; H04L9/302; H04L9/32; H04L9/321; H04L9/3247; H04L9/3249; H04L2209/00; H04L2209/56; H04L2209/60; H04L2209/608; H04L2209/80; H04L2209/805; H04L2209/88

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 130 words
A method for processing information, comprising the steps of: receiving information to be processed: defining a cryptographic comprehension function for the information, adapted for making at least a portion of the information incomprehensible; receiving asymmetric cryptographic key information, comprising at least asymmetric encryption key information and asymmetric decryption key information; negotiating a new cryptographic comprehension function between two parties to a communication using an intermediary; processing the information to invert the cryptographic comprehension function and impose the new cryptographic comprehension function in an integral process, in dependence on at least the asymmetric cryptographic key information, without providing the intermediary with sufficient asymmetric cryptographic key information to decrypt the processed information; and outputting processed information, wherein the ability of the asymmetric decryption key information to decrypt the processed information changes dynamically.
Claim 2
Independent Claim 130 words
A method for processing information, comprising the steps of: receiving information to be processed: defining a cryptographic comprehension function for the information, adapted for making at least a portion of the information incomprehensible; receiving asymmetric cryptographic key information, comprising at least asymmetric encryption key information and asymmetric decryption key information; negotiating a new cryptographic comprehension function between two parties to a communication using an intermediary; processing the information to invert the cryptographic comprehension function and impose the new cryptographic comprehension function in an integral process, in dependence on at least the asymmetric cryptographic key information, without providing the intermediary with sufficient asymmetric cryptographic key information to decrypt the processed information; and outputting processed information, wherein the ability of the asymmetric decryption key information to decrypt the processed information changes dynamically.
Claim 3
Dependent Claim 20 words
The method according to claim 1 , further comprising the step of accounting for a decryption of the processed information.
Claim 4
Dependent Claim 24 words
The method according to claim 1 , wherein the ability of the asymmetric decryption key information to decrypt the processed information changes over time.
Claim 5
Dependent Claim 44 words
The method according to claim 1 , wherein said new cryptographic comprehension function has a cryptographic security based on an asymmetry between a difficulty of exponentiation of a message with a number derived from at least two large prime numbers, and a factoring thereof.
Claim 6
Dependent Claim 29 words
The method according to claim 1 , wherein said integral process comprises exponentiation of a message with a cryptographic key derived from at least two pairs of large primes.
Claim 7
Dependent Claim 66 words
The method according to claim 1 , wherein said cryptographic comprehension function comprises an exponentiation of a message or a cryptographic key with a key derived from at least two large prime numbers, and said integral process comprises exponentiation of a message or a cryptographic key with a number derived by combining a complementary key with an additional key derived from at least two large primes.
Claim 8
Dependent Claim 59 words
The method according to claim 1 , wherein said cryptographic comprehension function comprises a first RSA-type asymmetric key encryption, and said integral process comprises applying a second RSA-type asymmetric key encryption using an encryption key formed by multiplying a decryption key for said first RSA-type asymmetric key encryption with an encryption key for a second RSA-type asymmetric key encryption.
Claim 9
Dependent Claim 42 words
The method according to claim 1 , wherein the received information comprises AES cryptographic key information, and said comprehension function comprises an RSA type encryption algorithm employing a composite key defined by a function of a public key and a private key.
Claim 10
Dependent Claim 40 words
The method according to claim 8 , wherein the sender authenticates himself and enters into a non-repudiatable transaction with a third party to obtain at least one of the required keys by signing a message with the sender private key.
Claim 11
Dependent Claim 67 words
The method according to claim 1 , wherein: said defining step comprises providing information encrypted with a large prime-number based asymmetric key encryption algorithm encrypted with a first key; and said processing step comprises processing the provided information with a modified large prime-number based asymmetric key encryption algorithm using a composite key comprising a function of an complementary key to said first key and a second key.
Claim 12
Dependent Claim 53 words
The method according to claim 1 , wherein at least one party to a communication of the processed information authenticates himself and enters into a non-repudiatable transaction with a third party to obtain at least a portion of the asymmetric cryptographic key information by signing a message with a respective party private key.
Claim 13
Dependent Claim 24 words
The method according to claim 1 , wherein said processing step is performed in a secure environment protected from a sender of the information.
Claim 14
Dependent Claim 152 words
The method according to claim 1 , further comprising the steps of: (a) defining first and second key pairs, having a compatible modulus; and (b) said processing step comprises exponentiating a message encrypted with the cryptographic comprehension function using a first key of the first key pair, with a product of a second key of the first key pair and a first key of the second key pair, and reducing according to the compatible modulus; to thereby yield a message encrypted with the first key of the second key pair, wherein the modulus (n) for a respective key pair is a composite number, constructed by multiplying two large numbers, derived from prime numbers, (p) and (q) together, and the respective first and second keys (d) and (e) of a respective key pair are related to each other and the modulus (n) in the following way: d=e −1 mod(( p− 1)( q− 1)).
Claim 15
Dependent Claim 65 words
The method according to claim 1 , wherein said defining step comprises providing information encrypted with an RSA-type asymmetric key encryption algorithm encrypted with a first RSA-type key; and said processing step comprises processing the provided information with a modified RSA-type asymmetric key algorithm using a composite key comprising a function of a complementary key to said first RSA-type key and a second RSA-type key.
Claim 16
Dependent Claim 111 words
The method according to claim 1 , further comprising the steps of: receiving, by an intermediary, an identifier of desired information and accounting information for a receiver and accounting for a transaction involving the information; transmitting an identifier of desired information and an intended recipient from the intermediary to a sender; negotiating, by the intermediary, the new cryptographic comprehension function for the information sent by the sender to the receiver, without providing the intermediary with information to decrypt either the information in accordance with the cryptographic comprehension function or the processed information in accordance with the new cryptographic comprehension function; and transmitting the processed information from the sender to the receiver.
Claim 17
Independent Claim 168 words
A method for communicating information between a first party and a second party, comprising the steps of: receiving, by an intermediary, an identifier of desired information, an authentication of the first party, and accounting information for a transaction involving the information, from the first party; generating, by the intermediary, a transcoding key for converting an encrypted file at the second party to a new encryption formation, having as components a decryption key for the encrypted file and a new encryption key; receiving, by the first party, the encrypted file having the new encryption format; and decrypting the encrypted file having the new encryption format with a decryption key associated with the transcoding key, wherein at least one of: an ability to decrypt the encrypted file having the new encryption format with the decryption key is sensitive to a dynamic parameter; and the encrypted content does not pass through the intermediary, and the intermediary does not possess sufficient information for decrypting the encrypted file having the new encryption format.
Claim 18
Independent Claim 168 words
A method for communicating information between a first party and a second party, comprising the steps of: receiving, by an intermediary, an identifier of desired information, an authentication of the first party, and accounting information for a transaction involving the information, from the first party; generating, by the intermediary, a transcoding key for converting an encrypted file at the second party to a new encryption formation, having as components a decryption key for the encrypted file and a new encryption key; receiving, by the first party, the encrypted file having the new encryption format; and decrypting the encrypted file having the new encryption format with a decryption key associated with the transcoding key, wherein at least one of: an ability to decrypt the encrypted file having the new encryption format with the decryption key is sensitive to a dynamic parameter; and the encrypted content does not pass through the intermediary, and the intermediary does not possess sufficient information for decrypting the encrypted file having the new encryption format.
Claim 19
Dependent Claim 31 words
The method according to claim 16 , wherein an intermediary provides information defining the transcoding key for said decrypting step, but does not have sufficient information to decrypt the encrypted file.
Claim 20
Dependent Claim 30 words
The method according to claim 16 , wherein an ability to decrypt the encrypted file having the new encryption format with the decryption key is sensitive to a dynamic parameter.
Claim 21
Dependent Claim 25 words
The method according to claim 16 , wherein the intermediary does not possess sufficient information for decrypting the encrypted file having the new encryption format.
Claim 22
Independent Claim 177 words
A method for processing information, comprising the steps of: storing a record in a first encrypted format; receiving a transaction request for the record from a requestor; financially accounting for a transaction involving the record; securely negotiating between the requestor and an intermediary, a decryption key for the record, said decryption key being different than an associated decryption key for said record in said first encrypted format; converting the record to a second encrypted format, without being represented in an unencrypted state during transition from the first encrypted format to the second encrypted format, and without providing sufficient information at the site of conversion to enable decryption of the record from the first or second encrypted format before, during or after conversion, such that the negotiated decryption key is selectively operative to decrypt the record in the second encrypted format; communicating the record encrypted in the second encrypted format to the requestor, without passing the record through the intermediary; and decrypting the record in the second encrypted format by the requester based on the negotiated decryption key.
Claim 23
Independent Claim 177 words
A method for processing information, comprising the steps of: storing a record in a first encrypted format; receiving a transaction request for the record from a requestor; financially accounting for a transaction involving the record; securely negotiating between the requestor and an intermediary, a decryption key for the record, said decryption key being different than an associated decryption key for said record in said first encrypted format; converting the record to a second encrypted format, without being represented in an unencrypted state during transition from the first encrypted format to the second encrypted format, and without providing sufficient information at the site of conversion to enable decryption of the record from the first or second encrypted format before, during or after conversion, such that the negotiated decryption key is selectively operative to decrypt the record in the second encrypted format; communicating the record encrypted in the second encrypted format to the requestor, without passing the record through the intermediary; and decrypting the record in the second encrypted format by the requester based on the negotiated decryption key.
Claim 24
Dependent Claim 25 words
The method according to claim 20 , wherein the intermediary is not provided with sufficient information to decrypt the record in the second encrypted format.
Claim 25
Independent Claim 251 words
A method for processing information, comprising the steps of: defining a cryptographic comprehension function adapted for making at least a portion of an information record incomprehensible, said cryptographic comprehension function having associated asymmetric cryptographic keys; generating, by an intermediary, a transcoding key for converting information encrypted with said cryptographic comprehension function to information encrypted with a new cryptographic comprehension function, having as components a decryption key for the encrypted information and a new encryption key; processing the information encrypted with said cryptographic comprehension function with the transcoding key to invert the cryptographic comprehension function and impose the new cryptographic comprehension function, without revealing the portion of the information record in an intermediate step; providing a first communications channel between a first and second party; providing a second communications channel between each of the first and second parties and the intermediary; communicating, by the intermediary through the second communications channel, with at least one of the first and second parties, information necessary for comprehension of the incomprehensible portion of the information record communicated over the first communications channel, wherein at least one of either: (a) the intermediary is neither provided with the portion of the information in a comprehensible or incomprehensible form, nor sufficient decryption information for the comprehension of the incomprehensible portion of the information record or (b) the ability of the information necessary for comprehension of the incomprehensible portion of the record changes dynamically; and communicating the processed information over the first communications channel between the first and second parties.
Claim 26
Independent Claim 251 words
A method for processing information, comprising the steps of: defining a cryptographic comprehension function adapted for making at least a portion of an information record incomprehensible, said cryptographic comprehension function having associated asymmetric cryptographic keys; generating, by an intermediary, a transcoding key for converting information encrypted with said cryptographic comprehension function to information encrypted with a new cryptographic comprehension function, having as components a decryption key for the encrypted information and a new encryption key; processing the information encrypted with said cryptographic comprehension function with the transcoding key to invert the cryptographic comprehension function and impose the new cryptographic comprehension function, without revealing the portion of the information record in an intermediate step; providing a first communications channel between a first and second party; providing a second communications channel between each of the first and second parties and the intermediary; communicating, by the intermediary through the second communications channel, with at least one of the first and second parties, information necessary for comprehension of the incomprehensible portion of the information record communicated over the first communications channel, wherein at least one of either: (a) the intermediary is neither provided with the portion of the information in a comprehensible or incomprehensible form, nor sufficient decryption information for the comprehension of the incomprehensible portion of the information record or (b) the ability of the information necessary for comprehension of the incomprehensible portion of the record changes dynamically; and communicating the processed information over the first communications channel between the first and second parties.
Claim 27
Dependent Claim 44 words
The method according to claim 22 , wherein said new cryptographic comprehension function has a cryptographic security based on an asymmetry between a difficulty of exponentiation of a message with a number derived from at least two large prime numbers, and a factoring thereof.
Claim 28
Dependent Claim 25 words
The method according to claim 22 , wherein the ability of the information necessary for comprehension of the incomprehensible portion of the record changes dynamically.
Claim 29
Dependent Claim 29 words
The method according to claim 22 , wherein the ability of the information necessary for comprehension of the incomprehensible portion of the record changes as a function of time.

References Cited (Backward Citations)

US4564840A Cited
US4200770A Cited
US4218582A Cited
US4405829A Cited
US4306111A Cited
US4365110A Cited
US4264782A Cited
US4309569A Cited
US4529870A Cited
US4326098A Cited
US4528588A Cited
US4595950A Cited
US4386233A Cited
US4351982A Cited
US4393269A Cited
US4399323A Cited
US4438824A Cited
US4514592A Cited
US4471164A Cited
US4453074A Cited
US4567600A Cited
US4458109A Cited
US4578531A Cited
US4558176A Cited
US4564018A Cited
US4590470A Cited
US4926480A Cited
US4819267A Cited
US4575621A Cited
US4625076A Cited
US4633036A Cited
US4734564A Cited
US4812628A Cited
US4736203A Cited
US4752676A Cited
US4890323A Cited
US4731841A Cited
US5020105A Cited
US5056141A Cited
US5586262A Cited
US4868376A Cited
US4896363A Cited
US4827518A Cited
US4941173A Cited
US4961142A Cited
US4926325A Cited
US4952928A Cited
US5508912A Cited
US4977595A Cited
US4972476A Cited
US5056147A Cited
US4993068A Cited
US5521722A Cited
US5623547A Cited
US5036461A Cited
US5646839A Cited
US5616904A Cited
US5779634A Cited
US5485519A Cited
US5528492A Cited
US6049610A Cited
US5781890A Cited
US6047887A Cited
US5898154A Cited
US5608387A Cited
US5920477A Cited
US5875108A Cited
US6081750A Cited
US5561718A Cited
US5483601A Cited
US6157914A Cited
US5553155A Cited
US5889474A Cited
US5534855A Cited
US5583950A Cited
US5954583A Cited
US5478993A Cited
US5912818A Cited
US5740244A Cited
US5546462A Cited
US5621889A Cited
US5832450A Cited
US6012035A Cited
US5519778A Cited
US5485312A Cited
US5644778A Cited
US5745604A Cited
US6026193A Cited
US5862260A Cited
US5850481A Cited
US5841978A Cited
US5832119A Cited
US5748763A Cited
US5768426A Cited
US5850481C1 Cited
US5841886A Cited
US5832119C1 Cited
US5799088A Cited
US5835726A Cited
US6049785A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2010-02-19 2010-08-21 2011-02-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2014-02-19 2014-08-21 2015-02-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2018-02-19 2018-08-21 2019-02-20 $7700.00 Window Closed / Lapsed

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