Patents by Inventor Venkata N. Padmanabhan

Venkata N. Padmanabhan 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).

  • Publication number: 20100195548
    Abstract: Embodiments of the claimed subject matter provide an approach to managing the power state of wireless network devices in a wireless network. Embodiments include a process for modifying the scheduling of data distribution device by referencing the data buffer in an access point for data intended for a wireless network client operating under a power-saving mode, and re-arranging the distribution queue of the access point to be granted priority for a time which coincides with the delivery of a polling beacon to the power-saving wireless client. Other embodiments include a method to create virtual access points for a particular usage, and to leverage access points in a wireless network for particular usages of devices in range.
    Type: Application
    Filed: January 30, 2009
    Publication date: August 5, 2010
    Applicant: MICROSOFT CORPORATION
    Inventors: Vishnu Navda, Ramachandran Ramjee, Venkata N. Padmanabhan, Shravan Rayanchu
  • Patent number: 7711846
    Abstract: A system and methodologies are disclosed for determining the geographic location of an Internet host. A first method infers host location based on the DNS names of the host of interest or other nearby network nodes. A second method employs network delay measurements from geographically distributed locations to triangulate the coordinates of the host. A third method couples partial host-to-location mapping information obtained from one or more sources with BGP or other routing information in order to infer location of the host of interest.
    Type: Grant
    Filed: July 16, 2007
    Date of Patent: May 4, 2010
    Assignee: Microsoft Corporation
    Inventors: Venkata N. Padmanabhan, Lakshminarayanan Subramanian
  • Patent number: 7675856
    Abstract: Measurement systems according to embodiments of the invention allow accurate bandwidth estimation even in non-FIFO scheduling and frame-level contention environments. In an embodiment of the invention, the approximate fraction of time that a link is idle is found by probing for idle periods (“gaps”). The fraction of idle time is then multiplied by the capacity to obtain an estimate of the available bandwidth. Gap time is estimated in an embodiment of the invention fraction by gathering samples of one-way delay (OWD) over the link in question. After the OWD is normalized and plotted, the knee in the cumulative distribution function (CDF) of OWD samples is used to identify the fraction of time that the channel is idle.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: March 9, 2010
    Assignee: Microsoft Corporation
    Inventors: Venkata N. Padmanabhan, Jitendra D. Padhye
  • Publication number: 20090323516
    Abstract: The method collects configuration data about the network, compares it to known good configurations to see if a corrective configuration is available. In addition, the method will review known bad configurations and determine if any of the successful corrective configurations for the bad configuration would be appropriate for the bad configuration under consideration.
    Type: Application
    Filed: June 27, 2008
    Publication date: December 31, 2009
    Applicant: MICROSOFT CORPORATION
    Inventors: Ranjita Bhagwan, Bhavish Aggarwal, Venkata N. Padmanabhan, Geoffrey M. Voelker
  • Patent number: 7640215
    Abstract: A system and method is provided for evaluating the effectiveness of data encryption for hiding the identity of the source of Web traffic. A signature is constructed from encrypted Web traffic for a Web page sent by a target Web site, and the signature is compared with archived traffic signatures obtained by accessing various Web pages of interest in advance. If the signature of the detected encrypted Web traffic matches a stored traffic signature beyond a pre-set statistical threshold, a positive match is found, and the source of the traffic is identified. Countermeasures for reducing the reliability of source identification based on traffic signature matching are provided.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: December 29, 2009
    Assignee: Microsoft Corporation
    Inventors: Yi-Min Wang, Qixiang Sun, Daniel R. Simon, Wilfred Russell, Lili Qiu, Venkata N. Padmanabhan
  • Publication number: 20090313282
    Abstract: Application service requests received by an application hosting framework are automatically differentiated and categorized, and resource usage patterns associated with the requests are predicted. Resource usage data points are successively extracted from the hosting framework. Elements of an initial resource usage pattern matrix are computed from the data points. An estimate for the number of categories of requests is computed from the initial resource usage pattern matrix, where the requests in each category have similar resource usage patterns. Elements of a resource usage signature matrix and request categorization matrix are computed from the estimate for the number of categories of requests and the initial resource usage pattern matrix.
    Type: Application
    Filed: June 13, 2008
    Publication date: December 17, 2009
    Applicant: Microsoft Corporation
    Inventors: Ranjita Bhagwan, Monojit Choudhury, Ravindran Kannan, Venkata N. Padmanabhan, Abhishek Sharma, Geoffrey Voelker
  • Publication number: 20090192688
    Abstract: A traffic sensing system for collecting information on traffic conditions is provided. A traffic sensing system includes a traffic sensing server and a mobile traffic sensing device that sends traffic reports to the traffic sensing server. An MTS device may use an accelerometer integrated into a smart phone to detect potholes, to detect when the vehicle is braking, to detect whether the MTS device is being transported via a vehicle or a pedestrian, to detect horns sounding, and so on. The MTS device reports the various conditions to the traffic sensing server for accurate assessment of traffic conditions at stretches of road through which vehicles transporting MTS devices travel.
    Type: Application
    Filed: June 26, 2008
    Publication date: July 30, 2009
    Applicant: Microsoft Corporation
    Inventors: Venkata N. Padmanabhan, Ramachandran Ramjee, Prashanth Mohan
  • Publication number: 20090187673
    Abstract: Described is transparently compressing content for network transmission, including end-to-end compression. An end host or middlebox device sender sends compressed packets to an end host or middlebox device receiver, which decompresses the packets to recover the original packet. The sender constructs compressed packets including references to information maintained at the receiver, which the receiver uses to access the information to recreate actual original packet content. The receiver may include a dictionary corresponding to the sender, e.g., synchronized with the sender's dictionary. Alternatively, in speculative compression, the sender does not maintain a dictionary, and instead sends a fingerprint (hash value) by which the receiver looks up corresponding content in its dictionary; if not found, the receiver requests actual content.
    Type: Application
    Filed: January 18, 2008
    Publication date: July 23, 2009
    Applicant: MICROSOFT CORPORATION
    Inventors: Ramachandran Ramjee, Ranjita Bhagwan, Venkata N. Padmanabhan, Manveer Singh Chawla
  • Publication number: 20090161554
    Abstract: A client-based collaborative approach called WebProfiler is used for diagnosing Web transaction failures. The WebProfiler leverages end-host cooperation to pool together observations on the success or failure of Web transactions from multiple vantage points. These observations are utilized by a collaborative blame attribution algorithm to identify a suspect network entity that caused the Web transaction failure.
    Type: Application
    Filed: February 27, 2009
    Publication date: June 25, 2009
    Applicant: Microsoft Corporation
    Inventors: Sharad Agarwal, Venkata N. Padmanabhan, Prashanth Mohan, Nikitas Liogkas
  • Publication number: 20090086652
    Abstract: Disclosed is a general model and method for computing performance bounds in multi-hop wireless networks. Rather than focusing on computing asymptotic performance bounds under assumptions of homogeneity or randomness in the network topology and/or workload, the present invention accommodates any given network, technology, interference model, routing paradigm, and workload. Using a conflict graph to formally characterize the impact of wireless interference on the performance of multi-hop wireless networks, methods for computing upper and lower bounds on the capacity of a given wireless network are detailed. Besides computing network capacity, the model and method disclosed can also enable or benefit other applications including maximizing fairness and minimizing maximum link utilization.
    Type: Application
    Filed: November 18, 2008
    Publication date: April 2, 2009
    Applicant: Microsoft Corporation
    Inventors: Kamal Jain, Jitendra D. Padhye, Venkata N. Padmanabhan, Lili Qiu
  • Publication number: 20090089438
    Abstract: An intelligent lookup service for a network is provided for clients of a network requesting services of the network that intelligently determines, based on a service requirement of the requested service, optimal service endpoint(s) for providing the requested service. The intelligent lookup service can incorporate predetermined mapping policy and traffic measurements into the determination. In addition, a feedback loop is provided from clients and/or service endpoints to the lookup service concerning measurements about prior connections in the network. The lookup service can include a set of beacons distributed in the network and against which measurements about the network are recorded. A client receives, from the lookup service in response to a request for a network address, a set of candidate service endpoints that pertain to the requested network address and the client connects to one of the candidate service endpoints based on policy or context.
    Type: Application
    Filed: September 27, 2007
    Publication date: April 2, 2009
    Applicant: MICROSOFT CORPORATION
    Inventors: Sharad Agarwal, Najam Ahmad, Behrooz Chitsaz, Manuel Silverio Da Silva Costa, Albert Gordon Greenberg, Parantap Lahiri, Venkata N. Padmanabhan
  • Publication number: 20090055502
    Abstract: A electronic communication system that can detect and adapt to delays in delivery of e-mail messages. The system may adapt to delays by using mechanisms other than the initially intended path to convey the information intended for delivery by e-mail. A possible adaptation is reprioritization of an e-mail message that is found to be experiencing a delay.
    Type: Application
    Filed: August 21, 2007
    Publication date: February 26, 2009
    Applicant: Microsoft Corporation
    Inventors: Sharad Agarwal, Venkata N. Padmanabhan, Rajatish Mukherjee
  • Publication number: 20090055490
    Abstract: A electronic communication system that can detect and adapt to delays in delivery of e-mail messages. The system may adapt to delays by using other mechanisms to convey the information intended for delivery by e-mail. Delays may be detected using a low-latency channel to send notifications of e-mails to recipients. The notifications are likely to be received in advance of a delayed e-mail, allowing an intended e-mail recipient to detect that delivery of an e-mail has been delayed. The recipient may adapt to the delay in delivery, when a notification is received without a corresponding electronic mail message. The notification may be small relative to an e-mail message but may include enough information to allow the recipient to identify the subject matter of the corresponding e-mail message, an importance level of the e-mail message, a preferred mechanism of the sender for out-of-band communications, and/or the location from which the e-mail was sent.
    Type: Application
    Filed: August 21, 2007
    Publication date: February 26, 2009
    Applicant: Microsoft Corporation
    Inventors: Sharad Agarwal, Venkata N. Padmanabhan, Rajatish Mukherjee
  • Publication number: 20090055491
    Abstract: A electronic communication system that can detect and adapt to delays in delivery of e-mail messages. The system may adapt to delays by using other mechanisms to convey the information intended for delivery by e-mail. Though, other reactions to delays are possible, including rescheduling events premised on delivery of information by e-mail. The system may use a low-latency notification channel in parallel with a channel used for e-mail delivery to detect actual delays for a specific e-mail message. Additionally, the system may detect potential delays based on historical delay information or other information indicating that a path over which an e-mail is to be sent may be experiencing delivery delays and may adapt to a potential delay before a message likely to experience the delay is sent.
    Type: Application
    Filed: August 21, 2007
    Publication date: February 26, 2009
    Applicant: Microsoft Corporation
    Inventors: Sharad Agarwal, Venkata N. Padmanabhan, Rajatish Mukherjee
  • Publication number: 20090055489
    Abstract: A electronic communication system that can detect and adapt to delays in delivery of e-mail messages. The system may adapt to delays by using other mechanisms to convey the information intended for delivery by e-mail. The mechanism may convey the information to the recipient once the delayed electronic mail message is received by the recipient's e-mail system. In this respect, the recipient may make arrangements to receive information in the e-mail message when the recipient expects to be away from his or her e-mail system. Additionally or alternatively, the recipient may choose to initiate out-of-band communication to the sender when the recipient receives an indication of a delayed electronic mail message.
    Type: Application
    Filed: August 21, 2007
    Publication date: February 26, 2009
    Applicant: Microsoft Corporation
    Inventors: Sharad Agarwal, Venkata N. Padmanabhan, Rajatish Mukherjee
  • Publication number: 20080320152
    Abstract: A computer in a network runs a verification procedure in which it sends data packets to another computer in the network. Some or all of the data packets contain, either individually or collectively, a secret piece of information, such as a secret code. The computer then makes a determination regarding the network links between it and the other computer. If, for example, the other computer is able to respond by providing the secret piece of information back, then the computer sending the data packets concludes that the devices along the network links en route to the other computer are properly forwarding data packets.
    Type: Application
    Filed: August 18, 2008
    Publication date: December 25, 2008
    Applicant: Microsoft Corporation
    Inventors: Venkata N. Padmanabhan, Daniel R. Simon
  • Patent number: 7469143
    Abstract: Disclosed is a general model and method for computing performance bounds in multi-hop wireless networks. Rather than focusing on computing asymptotic performance bounds under assumptions of homogeneity or randomness in the network topology and/or workload, the present invention accommodates any given network, technology, interference model, routing paradigm, and workload. Using a conflict graph to formally characterize the impact of wireless interference on the performance of multi-hop wireless networks, methods for computing upper and lower bounds on the capacity of a given wireless network are detailed. Besides computing network capacity, the model and method disclosed can also enable or benefit other applications including maximizing fairness and minimizing maximum link utilization.
    Type: Grant
    Filed: October 7, 2003
    Date of Patent: December 23, 2008
    Assignee: Microsoft Corporation
    Inventors: Kamal Jain, Jitendra D. Padhye, Venkata N. Padmanabhan, Lili Qiu
  • Patent number: 7436772
    Abstract: A new system and method of available bandwidth estimation applies even where the narrow link and tight link in a network path are in different locations. In embodiments of the invention, a unique packet probe series structure and processing is employed to estimate available bandwidth. In an embodiment of the invention, the spacing between probe packets is adjusted at the source to account for dilation caused by links leading to the tight link, so that the spacing is appropriate when the probes arrive at the tight link. Moreover, the multi-packet probe comprises a large packet followed by two much smaller packets. The large packet is then dropped once it has traversed the tight link. The two small packets, which are impacted little by subsequent narrow links, preserve the spacing set by the tight link, encoding the delay induced by the tight link, all the way to the destination.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: October 14, 2008
    Assignee: Microsoft Corporation
    Inventors: Jitendra D. Padhye, Venkata N. Padmanabhan
  • Patent number: 7426677
    Abstract: A data sequence may be encoded in a plurality of layers of multiple description coding. The layers of multiple description coding may include a first and a second layer of multiple description coding. The first layer of multiple description coding may include an initial part of a data sequence as well as forward error correction code for the initial part. The second layer of multiple description coding may include a next part of the data sequence as well as forward error correction code for the next part. A first set of data sequence breakpoints may be determined for the first layer of multiple description coding. A second set of data sequence breakpoints may be determined for the second layer. The data sequence may be encoded in the plurality of layers of multiple description coding as a function of the first and second sets of data sequence breakpoints.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: September 16, 2008
    Assignee: Microsoft Corporation
    Inventors: Philip Andrew Chou, Venkata N. Padmanabhan, Helen Wang
  • Patent number: 7421510
    Abstract: A computer network has links for carrying data among computers, including one or more client computers. Packet loss rates are determined for the client computers and, a system of equations is set up expressing the relationship between the loss rates at the client computers and the loss rates at the links. The system of equations is then solved using one or more linear programming techniques, and optimized by making an effort to find the most parsimonious solution.
    Type: Grant
    Filed: February 7, 2003
    Date of Patent: September 2, 2008
    Assignee: Microsoft Corporation
    Inventors: Venkata N. Padmanabhan, Lili Qiu