Patents by Inventor Henry Kwok

Henry Kwok 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: 10826823
    Abstract: A specification of network paths between a group of computer network routers is received and possible route paths between routers of the group of computer network routers are determined. A unique identifier is assigned to each route path of the possible route paths. A preferred route path of network traffic between a source computer network router and a destination computer network router among the group of computer network routers is determined and the unique identifier assigned to the preferred route path is identified. A specification of the identified unique identifier and a specification of at least a portion of the preferred route path that corresponds to the identified unique identifier are provided to at least the computer network routers in the preferred route path.
    Type: Grant
    Filed: July 31, 2018
    Date of Patent: November 3, 2020
    Assignee: Facebook, Inc.
    Inventors: Henry Kwok, Songqiao Su, Petr V. Lapukhov
  • Publication number: 20200044963
    Abstract: A specification of network paths between a group of computer network routers is received and possible route paths between routers of the group of computer network routers are determined. A unique identifier is assigned to each route path of the possible route paths. A preferred route path of network traffic between a source computer network router and a destination computer network router among the group of computer network routers is determined and the unique identifier assigned to the preferred route path is identified. A specification of the identified unique identifier and a specification of at least a portion of the preferred route path that corresponds to the identified unique identifier are provided to at least the computer network routers in the preferred route path.
    Type: Application
    Filed: July 31, 2018
    Publication date: February 6, 2020
    Inventors: Henry Kwok, Songqiao Su, Petr V. Lapukhov
  • Publication number: 20060074899
    Abstract: Mechanisms for storing and searching a hierarchy of policies and associations thereof are disclosed which may be particularly useful for implementing security protocols, such as, but not limited to Internet Protocol security (IPsec). For example, a hierarchy of policies is stored in a search priority order in an associative memory, with each association of a particular policy stored higher in the search priority than its associated policy and after any other policy. Therefore, a lookup operation on the associative memory will identify a matching association, if one, else its matching policy. A match of a policy instead of an association may result in a corresponding association being added in the appropriate location. For IPsec implementations, the lookup word is typically derived from the packet, with this packet being typically processed based on the identified policy or association.
    Type: Application
    Filed: November 13, 2005
    Publication date: April 6, 2006
    Applicant: CISCO TECHNOLOGY, INC., A CALIFORNIA CORPORATION
    Inventors: Thomas Enderwick, Henry Kwok, Ashwath Nagaraj
  • Patent number: 6988060
    Abstract: An alignment simulation method simulates the signal waveform for an alignment mark using various alignment methods as well as the signal strength for an alignment mark, which is useful in optimizing the thickness of one or more layers as well as the geometry of the mark. The simulation of signal strength is also useful in optimizing the thickness of a layer for artifact wafers. The alignment simulation method includes accurately modeling the alignment mark, including one or more layers of various thicknesses and materials. The accurate modeling of the alignment mark includes such things as smoothing regions of the alignment mark and generating lateral shifts of the layers. The model of the alignment mark is a series of small pixels, each including the thickness of the layers and the layers indices of refraction. Using scalar diffraction, a complex reflectivity is generated for each pixel and a fast fourier transform is performed on the series of pixels.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: January 17, 2006
    Assignee: Nikon Corporation
    Inventors: Paul Derek Coon, Henry Kwok Pang Chau, Arun Ananth Aiyer
  • Publication number: 20050010612
    Abstract: Mechanisms for storing and searching a hierarchy of items are disclosed which may be particularly useful for implementing security policies and security associations, such as, but not limited to Internet Protocol security (IPsec). A hierarchy of items is stored in a search priority order. Multiple element definitions and groups of elements are identified. Representations of the element definitions and elements are stored in a prioritized searchable data structure in decreasing search priority such that representations of each particular element definition is stored after representations of a set of particular elements associated with the particular element definition and before representations of lower priority element definitions and their associated elements. The element definitions may include Internet Protocol security policies and the elements may include Internet Protocol security associations. The searchable data structure may include an associative memory or a plurality of associative memory entries.
    Type: Application
    Filed: July 9, 2003
    Publication date: January 13, 2005
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Thomas Enderwick, Henry Kwok, Ashwath Nagaraj
  • Patent number: 6320345
    Abstract: A command trajectory drives a stage to produce a smooth motion while minimizing any vibrations or oscillations of the structure. The command trajectory provides an acceleration and a deceleration that have derivatives, known as the jerk, equal to zero at the beginning and end of the acceleration and deceleration periods. Because the jerk is equal to zero at the beginning and end of acceleration and deceleration, the influence of the reactive forces on the positioning system's structure is reduced, thereby minimizing oscillation of the structure. Moreover, the jerk is continuous throughout the acceleration and deceleration periods, resulting in a smooth continuous motion of the stage. The jerk on the stage during acceleration and deceleration has an adjustable duration to reduce the structural disturbances and decrease settling time.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: November 20, 2001
    Assignee: Nikon Corporation
    Inventors: Bausan Yuan, Kazuaki Saiki, Henry Kwok Pang Chau