Patents by Inventor Brian D. Zill

Brian D. Zill 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: 7616575
    Abstract: A system and method for link quality routing uses a weighted cumulative expected transmission time path metric. A system for routing in a multi-hop ad hoc network, and a method for measuring the link quality of a route in the network, include assignment of a weight to a link in accordance with an expected transmission time of a packet over the link, and a combining of individual link weights for a route into a path metric. The path metric accounts for interference among links that use a shared channel. In the calculation of the path metric, the expected transmission times of links that interfere with one another are added, while the expected transmission times for non-interfering links are considered separately.
    Type: Grant
    Filed: March 15, 2005
    Date of Patent: November 10, 2009
    Assignee: Microsoft Corporation
    Inventors: Jitendra D. Padhye, Richard P. Draves, Jr., Brian D. Zill
  • Patent number: 7516049
    Abstract: Wireless adapters are installed on one or more general purpose computing devices and are connected via a wireless network in an enterprise environment. The adapters are densely deployed at known locations throughout the environment and are configured as air monitors. The air monitors monitor wireless signals transmitted between transceiver devices and access points and records information about these signals. One or more analysis or inference engines may be deployed to analyze the signals received from the air monitors to obtain optimum performance and connectivity information about the wireless network.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: April 7, 2009
    Assignee: Microsoft Corporation
    Inventors: Brian D. Zill, Alastair Wolman, Jitendra D. Padhye, Paramvir Bahl, Ranveer Chandra
  • Publication number: 20080316982
    Abstract: Techniques for enhancing the throughput capacity available to client devices connected to a wireless local area network (WLAN) are described. Specifically, existing WLAN resources are converted into wireless access points (APs) to create a dense infrastructure of wireless APs. To leverage this dense AP infrastructure, central management techniques are employed. With client-to-AP mapping, these techniques are used to prevent the discovery of multiple APs in a WLAN by a client device and to select a single AP (using certain policies) to associate with the client device and provide it with an enhanced wireless connection to the WLAN. Additionally, techniques are employed to centrally determine, using central policies, when the AP should disassociate from the client device and when another centrally selected AP should respond to, and associate with, the client device to provide it with an enhanced wireless connection to the WLAN—without interrupting/disrupting the client device's access.
    Type: Application
    Filed: June 20, 2007
    Publication date: December 25, 2008
    Applicant: Microsoft Corporation
    Inventors: Rohan N. Murty, Ranveer Chandra, Jitendra D. Padhye, Alastair Wolman, Brian D. Zill
  • Publication number: 20080320108
    Abstract: Techniques for enhancing the throughput capacity available to client devices connected to a wireless local area network (WLAN) are described. Specifically, existing WLAN resources are converted into wireless access points (APs) to create a dense infrastructure of wireless APs. To leverage this dense AP infrastructure, central management techniques are employed. With client-to-AP mapping, these techniques are used to prevent the discovery of multiple APs in a WLAN by a client device and to select a single AP (using certain policies) to associate with the client device and provide it with an enhanced wireless connection to the WLAN. Additionally, techniques are employed to centrally determine, using certain policies, when the AP should disassociate from the client device and when another centrally selected AP should respond to, and associate with, the client device to provide it with an enhanced wireless connection to the WLAN—without interrupting/disrupting the client device's access.
    Type: Application
    Filed: June 20, 2007
    Publication date: December 25, 2008
    Applicant: Microsoft Corporation
    Inventors: Rohan N. Murty, Ranveer Chandra, Jitendra D. Padhye, Alastair Wolman, Brian D. Zill
  • Publication number: 20080200181
    Abstract: Wireless adapters are installed on one or more general purpose computing devices and are connected via a network in an enterprise environment. The adapters are densely deployed at known locations throughout the environment and are configured as air monitors. The air monitors monitor signals transmitted by one or more transceiver devices and records information about these signals. One or more analysis or inference engines may be deployed to obtain the recorded signal information and the air monitor locations to determine a location of the one or more wireless transceivers devices deployed in the environment.
    Type: Application
    Filed: May 24, 2007
    Publication date: August 21, 2008
    Applicant: MICROSOFT CORPORATION
    Inventors: Brian D. Zill, Alastair Wolman, Jitendra D. Padhye, Paramvir Bahl, Ranveer Chandra
  • Publication number: 20080201109
    Abstract: Wireless adapters are installed on one or more general purpose computing devices and are connected via a wireless network in an enterprise environment. The adapters are densely deployed at known locations throughout the environment and are configured as air monitors. The air monitors monitor wireless signals transmitted between transceiver devices and access points and records information about these signals. One or more analysis or inference engines may be deployed to analyze the signals received from the air monitors to obtain optimum performance and connectivity information about the wireless network.
    Type: Application
    Filed: February 28, 2007
    Publication date: August 21, 2008
    Applicant: MICROSOFT CORPORATION
    Inventors: Brian D. Zill, Alastair Wolman, Jitendra D. Padhye, Paramvir Bahl, Ranveer Chandra
  • Patent number: 7376122
    Abstract: Systems and methods for routing packets by nodes in an ad hoc network in accordance with a link quality source routing protocol are disclosed. Route discovery, route maintenance, and metric maintenance are designed to propagate and keep current link quality measurements. Metric maintenance includes a reactive approach for links that a node is currently using to route packets, and a proactive mechanism for all links. Nodes are configured to include a send buffer, a maintenance buffer, a request table, link quality metric modules, and preferably a neighbor cache and a link cache. The invention allows for asymmetric links in the network. The invention may be implemented within a virtual protocol interlayer between the link and network layers. The invention may employ any particular link quality metrics, including metrics based on probing techniques as well as metrics based on knowledge gained in other ways.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: May 20, 2008
    Assignee: Microsoft Corporation
    Inventors: Richard Powell Draves, Jr., Brian D. Zill, Jitendra D. Padhye
  • Publication number: 20070298779
    Abstract: A framework for wireless network management applications in an enterprise environment using existing general purpose computing devices is presented. At least one of the devices is configured with a wireless adapter and is used as an AirMonitor to monitor one or more wireless networks. Other devices are configured as LandMonitors to monitor traffic on a wired network in the enterprise environment. At least one inference engine uses the LandMonitors and AirMonitors by assigning them monitoring tasks. Data from the monitoring tasks are stored in a database. Analysis of the data that is computationally intensive is generally performed by the inference engines. Wireless network management applications use the framework by installing and running application-specific components (e.g., filters) on the AirMonitors, LandMonitors, and/or inference engines.
    Type: Application
    Filed: June 26, 2006
    Publication date: December 27, 2007
    Applicant: Microsoft Corporation
    Inventors: Alastair Wolman, Brian D. Zill, Jitendra D. Padhye, Paramvir Bahl, Ranveer Chandra
  • Publication number: 20070298720
    Abstract: A method of detecting rogue devices that are coupled to a wired network without generating false negative or false positive alerts is provided. When a wireless monitor detects an observed SSID and/or BSSID, various tests are run to determine whether the observed device is actually coupled to the wired network. To guard against the suspect device spoofing an authorized SSID and/or BSSID, location information is gathered so that the network administrator can pinpoint the location of the rogue device. If the device is not recognized, various other tests are run to determine whether the unrecognized device is actually connected to the wired network. These tests include an association test, a MAC address test, an ARP test, a packet replay test, a correlation test, and/or a DHCP fingerprint test. Once it is determined that the suspect device is a rogue connected to the wired network, an appropriate alert is generated.
    Type: Application
    Filed: October 25, 2006
    Publication date: December 27, 2007
    Applicant: Microsoft Corporation
    Inventors: Alastair Wolman, Brian D. Zill, Jitendra D. Padhye, Raveer Chandra, Paramvir Bahl, Manpreet Singh, Lenin Ravindranath Sivalingam
  • Patent number: 7134019
    Abstract: Disclosed is an authentication mechanism that enables an information recipient to ascertain that the information comes from the sender it purports to be from. This mechanism integrates a private/public key pair with selection by the sender of a portion of its address. The sender derives its address from its public key, for example, by using a hash of the key. The recipient verifies the association between the address and the sender's private key. The recipient may retrieve the key from an insecure resource and know that it has the correct key because only that key can produce the sender's address in the message. The hash may be made larger than the sender-selectable portion of the address. The recipient may cache public key/address pairs and use the cache to detect brute force attacks and to survive denial of service attacks. The mechanism may be used to optimize security negotiation algorithms.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: November 7, 2006
    Assignee: Microsoft Corporation
    Inventors: Art Shelest, David G. Thaler, Gregory O'Shea, Michael Roe, Brian D. Zill
  • Publication number: 20020152384
    Abstract: Disclosed is an authentication mechanism that enables an information recipient to ascertain that the information comes from the sender it purports to be from. This mechanism integrates a private/public key pair with selection by the sender of a portion of its address. The sender derives its address from its public key, for example, by using a hash of the key. The recipient verifies the association between the address and the sender's private key. The recipient may retrieve the key from an insecure resource and know that it has the correct key because only that key can produce the sender's address in the message. The hash may be made larger than the sender-selectable portion of the address. The recipient may cache public key/address pairs and use the cache to detect brute force attacks and to survive denial of service attacks. The mechanism may be used to optimize security negotiation algorithms.
    Type: Application
    Filed: November 13, 2001
    Publication date: October 17, 2002
    Applicant: Microsoft Corporation
    Inventors: Art Shelest, David G. Thaler, Gregory O'Shea, Michael Roe, Brian D. Zill