Patents by Inventor Alec Woo

Alec Woo 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: 8867544
    Abstract: A system and method adds and manages entries on a list of entries of routing information to allow the top entry to be used for routing to a destination corresponding to the list. Costs of a wireless link may be a function of the success rate experienced on that wireless link.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: October 21, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Alec Woo, David E. Culler
  • Patent number: 8819191
    Abstract: In one embodiment, each of a plurality of devices in a computer network is configured to i) transmit a unicasted dynamic host configuration protocol (DHCP) solicit message to a neighbor device having a route to a border router as an assumed DHCP relay without regard to location of a DHCP server, and ii) operate as a DHCP relay to receive unicasted DHCP solicit messages and relay the solicit message to the border router of the network without regard to location of the DHCP server, and to relay a DHCP reply to a corresponding requestor device.
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: August 26, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Lik Chuen Alec Woo, Wei Hong
  • Patent number: 8806573
    Abstract: Techniques are provided for the controlled scheduling of the authentication of devices in a lossy network, such as a mesh network. An authenticator device that is configured to authenticate devices in a lossy network receives an authentication start message from a particular device to be authenticated. The authenticator device determines a schedule for engaging in an authentication procedure for the particular device based on an indication of current network utilization.
    Type: Grant
    Filed: August 9, 2011
    Date of Patent: August 12, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Atul Mahamuni, Navindra Yadav, Jonathan Hui, Alec Woo, Wei Hong
  • Patent number: 8798048
    Abstract: A system and method adds and manages entries on a list of entries of routing information to allow the top entry to be used for routing to a destination corresponding to the list. Costs of a wireless link may be a function of the success rate experienced on that wireless link.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: August 5, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Alec Woo, David E. Culler
  • Publication number: 20140119200
    Abstract: A system and method adds and manages entries on a list of entries of routing information to allow the top entry to be used for routing to a destination corresponding to the list. Costs of a wireless link may be a function of the success rate experienced on that wireless link.
    Type: Application
    Filed: October 28, 2013
    Publication date: May 1, 2014
    Applicant: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Alec Woo, David E. Culler
  • Patent number: 8699368
    Abstract: In one embodiment, a transmitter in a communication network receives an indication of active transmission times of a receiver to which the transmitter attempts to reach with first transmissions, the active transmission times indicating respective times of second transmissions initiated by the receiver. Based on determining when the first transmissions occur, the transmitter may then compute a link reliability metric for a link from the transmitter to the receiver by excluding one or more of the first transmissions from the indicated active transmission times of the second transmissions. In one embodiment, the active transmission times are in the past and the reliability metric excludes any first transmissions in the past during those times, while in another embodiment the active transmission times are scheduled in the future and the reliability metric does not include any first transmissions since the first transmissions may be scheduled to avoid the active transmission times.
    Type: Grant
    Filed: July 26, 2011
    Date of Patent: April 15, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Lik Chuen Alec Woo, Wei Hong
  • Publication number: 20140092749
    Abstract: A system and method changes a rate at which routing information is sent to increase it upon the detection of one or more events, maintaining the then current rate for an amount of time, or dropping it, otherwise.
    Type: Application
    Filed: December 9, 2013
    Publication date: April 3, 2014
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Jonathan W. Hui, Alec Woo, David E. Culler
  • Patent number: 8670325
    Abstract: A system and method changes a rate at which routing information is sent to increase it upon the detection of one or more events, maintaining the then current rate for an amount of time, or dropping it, otherwise.
    Type: Grant
    Filed: November 3, 2008
    Date of Patent: March 11, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Jonathan W Hui, Alec Woo, David E Culler
  • Publication number: 20140064172
    Abstract: In one embodiment, a battery-operated communication device “quick-samples” a frequency hopping sequence at a periodic rate corresponding to a substantially low duty cycle, and is discovered by (e.g., attached to) a main-powered communication device. During a scheduled sample, the main-powered communication device transmits a control packet to be received by the battery-operated communication device, the control packet containing timing information and transmitted to account for worst-case clock drift error between the two devices. The battery-operated communication device responds to the control packet with a link-layer acknowledgment containing timing information from the battery-operated communication device. Accordingly, the two devices may re-synchronize their timing based on the timing information in the control packet and acknowledgment, respectively.
    Type: Application
    Filed: November 20, 2013
    Publication date: March 6, 2014
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Jonathan W. Hui, Lik Chuen Alec Woo, Wei Hong
  • Patent number: 8619789
    Abstract: In one embodiment, a battery-operated communication device “quick-samples” a frequency hopping sequence at a periodic rate corresponding to a substantially low duty cycle, and is discovered by (e.g., attached to) a main-powered communication device. During a scheduled sample, the main-powered communication device transmits a control packet to be received by the battery-operated communication device, the control packet containing timing information and transmitted to account for worst-case clock drift error between the two devices. The battery-operated communication device responds to the control packet with a link-layer acknowledgment containing timing information from the battery-operated communication device. Accordingly, the two devices may re-synchronize their timing based on the timing information in the control packet and acknowledgment, respectively.
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: December 31, 2013
    Assignee: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Lik Chuen Alec Woo, Wei Hong
  • Patent number: 8571030
    Abstract: A system and method adds and manages entries on a list of entries of routing information to allow the top entry to be used for routing to a destination corresponding to the list. Costs of a wireless link may be a function of the success rate experienced on that wireless link.
    Type: Grant
    Filed: November 3, 2008
    Date of Patent: October 29, 2013
    Assignee: Cisco Technology, Inc.
    Inventors: Jonathan W Hui, Alec Woo, David E Culler
  • Patent number: 8554965
    Abstract: A system and method stores wirelessly received communications for wireless retransmission, making space in a storage device, if necessary, by deleting any one or more communications corresponding to the same group as the received communication. If storage in the storage device remains insufficient, communications that have been previously retransmitted by that same device are deleted, according to one or more characteristics of such stored communications, such as age or number of times an instance of that communication has been received. If storage in the storage device remains insufficient, communications of a different group are deleted according to one or more characteristics of the stored communications.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: October 8, 2013
    Assignee: Cisco Technology, Inc.
    Inventors: Alec Woo, David E. Culler
  • Publication number: 20130094536
    Abstract: In one embodiment, a device in a frequency hopping communication network transmits responsive beacon messages based on adaptive types of responsive beacon message transmission based on a number of received beacon requests within a given time period: the number below a threshold results in synchronized unicast messages; the number above the threshold results in unsynchronized broadcast messages. In another embodiment, the device suppresses unsolicited beacon message transmission based on a density-aware redundancy count of other unsolicited beacon message transmissions from neighboring devices. In another embodiment, the device may transmit unsolicited beacon messages according to an adaptive interval based on stability of the network.
    Type: Application
    Filed: October 13, 2011
    Publication date: April 18, 2013
    Applicant: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Lik Chuen Alec Woo, Wei Hong
  • Publication number: 20130042301
    Abstract: Techniques are provided for the controlled scheduling of the authentication of devices in a lossy network, such as a mesh network. An authenticator device that is configured to authenticate devices in a lossy network receives an authentication start message from a particular device to be authenticated. The authenticator device determines a schedule for engaging in an authentication procedure for the particular device based on an indication of current network utilization.
    Type: Application
    Filed: August 9, 2011
    Publication date: February 14, 2013
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Atul Mahamuni, Navindra Yadav, Jonathan Hui, Alec Woo, Wei Hong
  • Publication number: 20130036305
    Abstract: According to one embodiment, techniques are provided to enable secure communication among devices in a mesh network using a group temporal key. An authenticator device associated with a mesh network stores a pairwise master key for each of a plurality of devices in a mesh network upon authentication of the respective devices. Using the pairwise master key, the authenticator device initiates a handshake procedure with a particular device in the mesh network to mutually derive a pairwise temporal key from the pairwise master key. The authenticator device encrypts and signs a group temporal key using the pairwise temporal key for the particular device and sends the group temporal key encrypted and signed with the pairwise temporal key to the particular device.
    Type: Application
    Filed: August 3, 2011
    Publication date: February 7, 2013
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Navindra Yadav, Atul Mahamuni, Jonathan Hui, Wei Hong, Alec Woo
  • Patent number: 8370693
    Abstract: A system and method communicates commands from a command originator to receiving devices, yet the receiving devices do not confirm receipt of the command. The most current command (e.g. the one with the highest sequence number) is rebroadcast by the command originator and the receiving devices, tending to be more frequent upon detection of an event indicating that the most current command was not received by at least one other device, and less frequently upon detection of an event indicating that the most current command was provided with sufficient duplication that if another device could receive it, the device likely did receive it, subject to a maximum and minimum rate.
    Type: Grant
    Filed: February 6, 2012
    Date of Patent: February 5, 2013
    Assignee: Cisco Technology, Inc.
    Inventors: Alec Woo, David E. Culler
  • Publication number: 20130028295
    Abstract: In one embodiment, a device in a frequency hopping communication network operate in a first mode according to a common broadcast schedule for the network that simultaneously overlays a first configured portion of all independently determined unicast listening schedules in the network. In response to determining a power outage condition, the device switches to operation in a power outage mode where the common broadcast schedule for the network in the power outage mode simultaneously overlays a second configured portion of all independently determined unicast listening schedules in the network, the second configured portion greater than the first configured portion. In one embodiment, the device broadcasts one or more power outage notifications (PONs) in response to determining the power outage condition as a reduction of a main power supply at the device. In another embodiment, the device receives a PON while powered as the power outage condition.
    Type: Application
    Filed: July 28, 2011
    Publication date: January 31, 2013
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Jonathan W. Hui, Wei Hong, Lik Chuen Alec Woo
  • Publication number: 20130028103
    Abstract: In one embodiment, a transmitter in a communication network receives an indication of active transmission times of a receiver to which the transmitter attempts to reach with first transmissions, the active transmission times indicating respective times of second transmissions initiated by the receiver. Based on determining when the first transmissions occur, the transmitter may then compute a link reliability metric for a link from the transmitter to the receiver by excluding one or more of the first transmissions from the indicated active transmission times of the second transmissions. In one embodiment, the active transmission times are in the past and the reliability metric excludes any first transmissions in the past during those times, while in another embodiment the active transmission times are scheduled in the future and the reliability metric does not include any first transmissions since the first transmissions may be scheduled to avoid the active transmission times.
    Type: Application
    Filed: July 26, 2011
    Publication date: January 31, 2013
    Applicant: Cisco Technology, Inc.
    Inventors: Jonathan W. Hui, Lik Chuen Alec Woo, Wei Hong
  • Publication number: 20130016757
    Abstract: In one embodiment, a battery-operated communication device “quick-samples” a frequency hopping sequence at a periodic rate corresponding to a substantially low duty cycle, and is discovered by (e.g., attached to) a main-powered communication device. During a scheduled sample, the main-powered communication device transmits a control packet to be received by the battery-operated communication device, the control packet containing timing information and transmitted to account for worst-case clock drift error between the two devices. The battery-operated communication device responds to the control packet with a link-layer acknowledgment containing timing information from the battery-operated communication device. Accordingly, the two devices may re-synchronize their timing based on the timing information in the control packet and acknowledgment, respectively.
    Type: Application
    Filed: July 12, 2011
    Publication date: January 17, 2013
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Jonathan W. Hui, Lik Chuen Alec Woo, Wei Hong
  • Publication number: 20130016758
    Abstract: In one embodiment, each device in a frequency hopping communication network independently determines its own local unicast listening schedule, and discovers a neighbor unicast listening schedule for each of its neighbors. The devices also synchronize to a common broadcast schedule for the network that simultaneously overlays a configured portion of all unicast listening schedules in the network. Accordingly, the device operate in a receive mode according to their local unicast listening schedule and the common broadcast schedule during the overlaid configured portion, and in a transmit mode according to each neighbor unicast listening schedule and the common broadcast schedule during the overlaid configured portion depending upon a destination of transmitted traffic.
    Type: Application
    Filed: July 12, 2011
    Publication date: January 17, 2013
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Jonathan W. Hui, Wei Hong, Lik Chuen Alec Woo