Patents by Inventor Lawrence W. Tang

Lawrence W. Tang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11671279
    Abstract: The various examples are directed to establishing a secure session between a device and a server. The device and the server may establish a session key. The session key may be used for encrypting data. After authenticating the session key, the server may transmit secure session data to the device, and the device may store the secure session data. The server may transmit information for deriving, based on secure session data, the session key to a different server. The device may transmit the secure session data to the server, or to the different server, to re-establish the secure session. The different server may derive, using the information and based on the secure session data, the session key. The different server may re-establish, using the session key, the secure session.
    Type: Grant
    Filed: July 25, 2022
    Date of Patent: June 6, 2023
    Assignee: Combined Conditional Access Development And Support, LLC
    Inventor: Lawrence W. Tang
  • Publication number: 20220360468
    Abstract: The various examples are directed to establishing a secure session between a device and a server. The device and the server may establish a session key. The session key may be used for encrypting data. After authenticating the session key, the server may transmit secure session data to the device, and the device may store the secure session data. The server may transmit information for deriving, based on secure session data, the session key to a different server. The device may transmit the secure session data to the server, or to the different server, to re-establish the secure session. The different server may derive, using the information and based on the secure session data, the session key. The different server may re-establish, using the session key, the secure session.
    Type: Application
    Filed: July 25, 2022
    Publication date: November 10, 2022
    Inventor: Lawrence W. Tang
  • Patent number: 11418364
    Abstract: The various examples are directed to establishing a secure session between a device and a server. The device and the server may establish a session key. The session key may be used for encrypting data. After authenticating the session key, the server may transmit secure session data to the device, and the device may store the secure session data. The server may transmit information for deriving, based on secure session data, the session key to a different server. The device may transmit the secure session data to the server, or to the different server, to re-establish the secure session. The different server may derive, using the information and based on the secure session data, the session key. The different server may re-establish, using the session key, the secure session.
    Type: Grant
    Filed: June 7, 2017
    Date of Patent: August 16, 2022
    Assignee: Combined Conditional Access Development And Support, LLC
    Inventor: Lawrence W. Tang
  • Patent number: 11115201
    Abstract: An encryption key may be generated based on personalized unit data associated with a software download recipient, for example, a secure processor. In some aspects, the secure processor may generate a decryption key based on its personalized unit data, and a software download may be performed between the software provider and the secure processor using the generated encryption keys. The secure processor may then decrypt and load the software for execution. The encryption and decryption key generation may also be based on a sequence number or other data indicating one or more previous software downloads at the secure processor. Using the sequence number or other data, sequences of multiple encryption and/or decryption keys may be generated to support multiple software downloads to a secure processor.
    Type: Grant
    Filed: June 19, 2014
    Date of Patent: September 7, 2021
    Assignee: Combined Conditional Access Development And Support, LLC
    Inventors: Lawrence W. Tang, Douglas M. Petty, Michael T. Habrat
  • Publication number: 20210160088
    Abstract: Methods for system component pairing and authentication are described. A challenge message is transmitted to a device. A reply message is received from the device in response to the challenge message. A length of time between transmitting the challenge message and receiving the reply message is determined. The length of time between transmitting the challenge message and receiving the reply message is compared to an expected time. Whether the reply message was received from the device is determined based on the comparing the length of time to the expected time. Communication is enabled with the device based on the determining that the reply message was received from the device.
    Type: Application
    Filed: February 6, 2021
    Publication date: May 27, 2021
    Inventors: Lawrence W. Tang, Douglas M. Petty
  • Patent number: 10944579
    Abstract: Methods for system component pairing and authentication are described. A first system component may pair with a second system component in response to receiving a unique identifier from the second system component. The first system component may store the received unique identifier and, thereafter, may authenticate that it is, in fact, communicating with the second system component. The first component may communicate a challenge message directed to the second system component and if the contents of the reply message and the time taken to receive the reply message do not correspond to expected values, the first component may determine that it may not be communicating with the intended second component and may cease communications with the second component.
    Type: Grant
    Filed: May 26, 2017
    Date of Patent: March 9, 2021
    Assignee: Combined Conditional Access Development and Support, LLC
    Inventors: Lawrence W. Tang, Douglas M. Petty
  • Publication number: 20180357432
    Abstract: The various examples are directed to establishing a secure session between a device and a server. The device and the server may establish a session key. The session key may be used for encrypting data. After authenticating the session key, the server may transmit secure session data to the device, and the device may store the secure session data. The server may transmit information for deriving, based on secure session data, the session key to a different server. The device may transmit the secure session data to the server, or to the different server, to re-establish the secure session. The different server may derive, using the information and based on the secure session data, the session key. The different server may re-establish, using the session key, the secure session.
    Type: Application
    Filed: June 7, 2017
    Publication date: December 13, 2018
    Inventor: Lawrence W. Tang
  • Publication number: 20180343250
    Abstract: Methods for system component pairing and authentication are described. A first system component may pair with a second system component in response to receiving a unique identifier from the second system component. The first system component may store the received unique identifier and, thereafter, may authenticate that it is, in fact, communicating with the second system component. The first component may communicate a challenge message directed to the second system component and if the contents of the reply message and the time taken to receive the reply message do not correspond to expected values, the first component may determine that it may not be communicating with the intended second component and may cease communications with the second component.
    Type: Application
    Filed: May 26, 2017
    Publication date: November 29, 2018
    Inventors: Lawrence W. Tang, JR., Douglas M. Petty
  • Patent number: 8958550
    Abstract: An apparatus, method, system and computer-readable medium are provided for preserving an encryption of data when confronted by an attack, such as a side channel analysis (SCA) attack based on a statistical analysis. In some embodiments, hardware, software, and/or firmware associated with an encryption calculation may be exercised or accessed during a background operation when an actual or real operation is not taking place. During the background operation, dummy values for data and one or more keys may be input to the hardware. A switching between the real operation and the background operation may take place seamlessly such that measurement of a physical characteristic associated with the hardware is indistinguishable in terms of when the real and background operations are active. In this manner, the secrecy of a key used in connection with the real operation may be preserved.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: February 17, 2015
    Assignee: Combined Conditional Access Development & Support. LLC (CCAD)
    Inventors: Lawrence W. Tang, An Tonthat
  • Publication number: 20140376718
    Abstract: An encryption key may be generated based on personalized unit data associated with a software download recipient, for example, a secure processor. In some aspects, the secure processor may generate a decryption key based on its personalized unit data, and a software download may be performed between the software provider and the secure processor using the generated encryption keys. The secure processor may then decrypt and load the software for execution. The encryption and decryption key generation may also be based on a sequence number or other data indicating one or more previous software downloads at the secure processor. Using the sequence number or other data, sequences of multiple encryption and/or decryption keys may be generated to support multiple software downloads to a secure processor.
    Type: Application
    Filed: June 19, 2014
    Publication date: December 25, 2014
    Inventors: Lawrence W. Tang, Douglas M. Petty, Michael T. Habrat
  • Patent number: 8792637
    Abstract: An encryption key may be generated based on personalized unit data associated with a software download recipient, for example, a secure processor. In some aspects, the secure processor may generate a decryption key based on its personalized unit data, and a software download may be performed between the software provider and the secure processor using the generated encryption keys. The secure processor may then decrypt and load the software for execution. The encryption and decryption key generation may also be based on a sequence number or other data indicating one or more previous software downloads at the secure processor. Using the sequence number or other data, sequences of multiple encryption and/or decryption keys may be generated to support multiple software downloads to a secure processor.
    Type: Grant
    Filed: November 22, 2011
    Date of Patent: July 29, 2014
    Assignee: Combined Conditional Access Development & Support, LLC
    Inventors: Lawrence W Tang, Douglas M Petty, Michael T Habrat
  • Publication number: 20130129086
    Abstract: An encryption key may be generated based on personalized unit data associated with a software download recipient, for example, a secure processor. In some aspects, the secure processor may generate a decryption key based on its personalized unit data, and a software download may be performed between the software provider and the secure processor using the generated encryption keys. The secure processor may then decrypt and load the software for execution. The encryption and decryption key generation may also be based on a sequence number or other data indicating one or more previous software downloads at the secure processor. Using the sequence number or other data, sequences of multiple encryption and/or decryption keys may be generated to support multiple software downloads to a secure processor.
    Type: Application
    Filed: November 22, 2011
    Publication date: May 23, 2013
    Applicant: COMBINED CONDITIONAL ACCESS DEVELOPMENT AND SUPPORT, LLC.
    Inventors: Lawrence W. Tang, Douglas M. Petty, Michael T. Habrat
  • Publication number: 20130064362
    Abstract: An apparatus, method, system and computer-readable medium are provided for preserving an encryption of data when confronted by an attack, such as a side channel analysis (SCA) attack based on a statistical analysis. In some embodiments, hardware, software, and/or firmware associated with an encryption calculation may be exercised or accessed during a background operation when an actual or real operation is not taking place. During the background operation, dummy values for data and one or more keys may be input to the hardware. A switching between the real operation and the background operation may take place seamlessly such that measurement of a physical characteristic associated with the hardware is indistinguishable in terms of when the real and background operations are active. In this manner, the secrecy of a key used in connection with the real operation may be preserved.
    Type: Application
    Filed: September 13, 2011
    Publication date: March 14, 2013
    Applicant: COMCAST CABLE COMMUNICATIONS, LLC
    Inventors: Lawrence W. Tang, An Tonthat
  • Patent number: 8385555
    Abstract: A content delivery network and method employing a Downloadable Conditional Access System (“DCAS”) includes first and second personalization servers. A unit key list having unique keys is segmented into different blocks. Each block is encrypted with a separate transmission key corresponding to that block such that first and second blocks are respectively encrypted with first and second transmission keys. The encrypted blocks are communicated to the personalization servers. The first transmission key is communicated to the first personalization server without being communicated to another personalization server such that the first server can decrypt the first block using the first transmission key to access the keys of the first block. The second transmission key is communicated to the second personalization server without being communicated to another personalization server such that the second server can decrypt the second block using the second transmission key to access the keys of the second block.
    Type: Grant
    Filed: December 10, 2008
    Date of Patent: February 26, 2013
    Assignee: Combined Conditional Access Development and Support, LLC.
    Inventors: Lawrence W. Tang, Eric E. Berry
  • Patent number: 8156560
    Abstract: The present invention discloses an apparatus and method for defining and enforcing rules of transition between two security domains, e.g., a transport domain and a persistent security domain. In turn, a border guard, e.g., a security device, is provided between these two domains that enforce rules for transition between the two security domains. This novel approach of defining a transport domain and a persistent security domain simplifies the classification of the digital content and its movement through the system. Namely, the border guard once established between the two systems can enforce DRM rules associated with how contents are moved between the two domains.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: April 10, 2012
    Assignee: General Instrument Corporation
    Inventors: John I. Okimoto, Bridget D. Kimball, Annie O. Chen, Michael T. Habrat, Douglas M. Petty, Eric Sprunk, Lawrence W. Tang
  • Patent number: 7929483
    Abstract: The present invention discloses a system and method for providing a secured system time reference to a subscriber device, e.g., a set top box or a receiver. In one embodiment, the system time reference is provided in a secure system time message that is broadcasted to a plurality of subscriber devices. Each subscriber device has a security device or software application that is capable of determining whether the received system time reference is legitimate. If the system time reference is determined to be legitimate, a local time reference is synchronized with said received system time reference.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: April 19, 2011
    Assignee: General Instrument Corporation
    Inventors: Bridget D. Kimball, Michael T. Habrat, John I. Okimoto, Douglas M. Petty, Eric J. Sprunk, Lawrence W. Tang
  • Patent number: 7764793
    Abstract: According to one embodiment of the invention a system is utilized to leverage the security arrangement between a first and second device to establish a secure link between the first device and a third device. One embodiment of the invention is particularly suitable for loading security data on a set top box, such as that utilized in the cable television industry.
    Type: Grant
    Filed: October 20, 2005
    Date of Patent: July 27, 2010
    Assignee: General Instrument Corporation
    Inventors: Xin Qiu, Bridget D. Kimball, Eric J. Sprunk, Lawrence W. Tang
  • Publication number: 20100142712
    Abstract: A content delivery network and method employing a Downloadable Conditional Access System (“DCAS”) includes first and second personalization servers. A unit key list having unique keys is segmented into different blocks. Each block is encrypted with a separate transmission key corresponding to that block such that first and second blocks are respectively encrypted with first and second transmission keys. The encrypted blocks are communicated to the personalization servers. The first transmission key is communicated to the first personalization server without being communicated to another personalization server such that the first server can decrypt the first block using the first transmission key to access the keys of the first block. The second transmission key is communicated to the second personalization server without being communicated to another personalization server such that the second server can decrypt the second block using the second transmission key to access the keys of the second block.
    Type: Application
    Filed: December 10, 2008
    Publication date: June 10, 2010
    Applicant: COMCAST CABLE HOLDINGS, LLC
    Inventors: Lawrence W. Tang, Eric E. Berry
  • Patent number: 7305555
    Abstract: A system is described for uniquely mating components of a communication network such as a smartcard and a set-top box. When mated, the smartcard and set-top box are tied together and have a single identity. Further, the smartcard operates properly only when inserted into an authorized set-top box. Exchanges of information between both components are secured by encryption and authentication to guard against piracy of the exchanged information. The system provides the same authentication key to the set-top box and the smartcard. This key is used for authenticating communication between the set-top box and the smartcard. First, the authentication key is encrypted by a set-top box mating key. The set-top box employs this mating key to decrypt the authentication key. After it is derived, the authentication key is stored in the set-top box's memory. Further, the same authentication key is encrypted by a smartcard mating key.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: December 4, 2007
    Assignee: General Instrument Corporation
    Inventors: John I. Okimoto, Eric J. Sprunk, Lawrence W. Tang, Annie On-yee Chen, Bridget Kimball, Douglas Petty
  • Patent number: 7257227
    Abstract: A method for forwarding messages containing cryptographic keys from a conditional access system that controls a population of set-top boxes to an encryption renewal system. The method includes storing a fictitious address of a virtual set-top box; generating a message based on the fictitious address, the message containing a cryptographic key; and forwarding the message to the fictitious address of the virtual set-top box. The encryption renewal system has information regarding the virtual set-top box, and is the recipient of the message. In addition, the encryption renewal system is for controlling access to pre-encrypted content generated by an encryption device.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: August 14, 2007
    Assignee: General Instrument Corporation
    Inventors: Annie On-yee Chen, Lawrence W. Tang, Akiko Wakabayashi