Patents by Inventor Ramachandran Ramjee

Ramachandran Ramjee 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: 8345616
    Abstract: A method scheduling outgoing communication in a mobile device is provided. The method includes receiving a signal quality profile for an area in which the device is located. The method further includes receiving a signal from a user application stored on the device that requests the mobile device to make the outgoing communication. Additionally, the method includes determining a current location, a speed, a direction, and a signal quality associated with the device and determining whether the signal quality is above a certain threshold. If not, the method includes predicting a future time at which the signal quality will be above the threshold based at least on the current location, the speed, the direction, the signal quality, and the signal quality profile. Finally, the method includes scheduling the outgoing communication from the mobile device at the future time.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: January 1, 2013
    Assignee: Microsoft Corporation
    Inventors: Vishnu Navda, Ramachandran Ramjee, Aaron Schulman, Venkata N. Padmanabhan, Kamal Jain
  • Publication number: 20120322497
    Abstract: One or more techniques and/or systems are disclosed for predicting when a signal handoff may occur from a current base station to a neighboring base station for a mobile device. An indication of signal strength between the mobile device and the current base station and an indication of signal strength between the mobile device and a (e.g., closest) neighboring base station can be monitored by the mobile device. A difference between these signal strength indications can be determined and compared against a threshold (e.g., based upon historical signal handoffs) to predict when and/or where a signal handoff may occur. The predicted signal handoff may be determined by the mobile device and a corresponding notification can be provided so that appropriate action may be taken (e.g., a user may not initiate a call and/or an application may not attempt to communicate data).
    Type: Application
    Filed: June 15, 2011
    Publication date: December 20, 2012
    Applicant: Microsoft Corporation
    Inventors: Vishnu Navda, Ramachandran Ramjee, Venkata N. Padmanabhan, Anand Padmanabha Iyer
  • Publication number: 20120321009
    Abstract: A multiple independent narrow-channel wireless network and method for transmitting and received data over a wireless network using a fragmented frequency spectrum. The system and method uses a plurality of narrow wireless channels obtained from splitting a wide wireless channel. Each narrow channel performs sending, receiving, and carrier sensing. Moreover, each narrow channel is independent such that data can be sent or received without any interference from other narrow channels and without synchronization. Embodiments of the system and method include a compound radio having a compound receiver and a compound transmitter. The compound transmitter includes an inter-radiolet symbol synchronization module, to permit use of a single inverse fast Fourier transform block, and a dynamically configurable filter array, to mitigate leakage between channels. The compound receiver uses fraction data rate processing to optimize efficiency.
    Type: Application
    Filed: June 17, 2011
    Publication date: December 20, 2012
    Applicant: Microsoft Corporation
    Inventors: Krishna Kant Chintalapudi, Bozidar Radunovic, Horia Vlad Balan, Michael Buettner, Vishnu Navda, Ramachandran Ramjee
  • Publication number: 20120320887
    Abstract: The claimed subject matter provides a method for wireless communications. The method includes transmitting, by a first node in a wireless network, a first preamble. The method also includes detecting, in parallel with transmitting the first preamble, a transmission of a second preamble. A second node in the wireless network transmits the second preamble. Additionally, the method includes determining a later start between the transmission of the first preamble and the transmission of the second preamble. The method further includes terminating transmission of the first preamble the determining indicates that the transmission of the first preamble started after the transmission of the second preamble.
    Type: Application
    Filed: June 17, 2011
    Publication date: December 20, 2012
    Applicant: Microsoft Corporation
    Inventors: Krishna Kant Chintalapudi, Bozidar Radunovic, Ramachandran Ramjee, Eugenio Magistretti
  • Publication number: 20120281520
    Abstract: A SoftRouter architecture deconstructs routers by separating the control entities of a router from its forwarding components, enabling dynamic binding between them. In the SoftRouter architecture, control plane functions are aggregated and implemented on a few smart servers which control forwarding elements that are multiple network hops away. A dynamic binding protocol performs network-wide control plane failovers. Network stability is improved by aggregating and remotely hosting routing protocols, such as OSPF and BGP. This results in faster convergence, lower protocol messages processed, and fewer route changes following a failure. The SoftRouter architecture includes a few smart control entities that manage a large number of forwarding elements to provide greater support for network-wide control. In the SoftRouter architecture, routing protocols operate remotely at a control element and control one or more forwarding elements by downloading the forwarding tables, etc. into the forwarding elements.
    Type: Application
    Filed: November 7, 2011
    Publication date: November 8, 2012
    Inventors: Furquan Ahmed Ansari, Martin Havemann, Tirunell V. Lakshman, Thyagarajan Nandagopal, Ramachandran Ramjee, Thomas Y. Woo
  • Patent number: 8301081
    Abstract: A communication device cognitively monitors interference signals across a communication band so that adaptations for physical and medium access control (MAC) of data packet transmissions are appropriate for a particular interference signal. Characteristics of an interference signal of interest (e.g., bandwidth, power and/or duration relative to an average data packet transmitted over a communication channel of the communication device) are sensed for an appropriate adaptation (e.g., forward error correction, modulation technique, back off, request to send/clear to send protocol, etc.). Patterns for known types of interference sources can be compared so that when recognized an associated adaptation can be used.
    Type: Grant
    Filed: November 13, 2007
    Date of Patent: October 30, 2012
    Assignee: Microsoft Corporation
    Inventors: Bernard D. Aboba, Paramvir Bahl, Gopala S. Narlanka, Jitendra D. Padhye, Bozidar Radunovic, Ramachandran Ramjee, Kun Tan, Miguel Oom Temudo de Castro
  • Patent number: 8271814
    Abstract: Energy saving virtualization technique embodiments are presented that save energy by virtualizing a network-connected client computer's computing session (or a part thereof) as a virtual machine (VM) and then migrating it between the client computer and a VM server, depending on whether the computing session is active or idle. The client computer VM is migrated to the VM server when the client computer is deemed to be idle, and the VM is migrated back when the client computer is deemed to have re-entered an active condition. When the VM has been migrated away from the client computer and is residing on the VM server, the client computer is put into a sleep mode, thereby saving energy. However, the user's computing session remains alive on the VM server so that ongoing network connections and other activity are not disturbed.
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: September 18, 2012
    Assignee: Microsoft Corporation
    Inventors: Venkata N. Padmanabhan, Ramachandran Ramjee, Tathagata Das, Pradeep Padala
  • Patent number: 8243601
    Abstract: A routing protocol, according to one embodiment of which a first station of a wireless network monitors its outgoing transmissions corresponding to a traffic flow for occurrence of multi-tier signals and for ability to achieve a specified minimum transmission rate. Based on the monitoring, the first station may transmit an outgoing solicitation message that identifies the monitored traffic flow as a candidate for rerouting. Upon receipt of the solicitation message, a second station of the wireless network evaluates whether rerouting of the monitored traffic flow through the second station is capable of increasing data throughput for that traffic flow without decreasing data throughputs for other traffic flows presently handled by the second station. Based on this evaluation, the second station may transmit to the first station an offer to reroute the monitored traffic flow. The first station, in turn, evaluates this offer, e.g.
    Type: Grant
    Filed: May 21, 2008
    Date of Patent: August 14, 2012
    Assignee: Alcatel Lucent
    Inventors: Li Li, Harish Viswanathan, Ramachandran Ramjee
  • Patent number: 8230106
    Abstract: Techniques and systems for managing transmissions from a TCP source by regulating the flow of acknowledgement signals to the TCP source are described. An acknowledgement signal regulator monitors a data queue used to buffer data packets received from the TCP source and an acknowledgement signal queue used to store acknowledgement signals to be transmitted to the TCP source. An acknowledgement signal release manager determines the available space in the data queue and the expected number of data packets arriving at the data queue, and manages the release of acknowledgement signals from the acknowledgement signal queue to the TCP source so as to prevent an undesired overflow of the data queue resulting from the arrival of an excessive number of data packets from the TCP source.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: July 24, 2012
    Assignee: Alcatel Lucent
    Inventors: Mun-Choon Chan, Ramachandran Ramjee
  • Patent number: 8149752
    Abstract: A medium-access-control (MAC) scheduler, according to one embodiment of which a station of a wireless network evaluates data throughputs corresponding to three different transmission configurations for transmission of a packet over a first of that station's wireless links. The first and second of those transmission configurations have the packet encoded in the first and second tiers, respectively, of a two-tier signal. The third transmission configuration has the packet encoded as a conventional single-tier signal. For each of the first and second transmission configurations, the station selects a second of that station's wireless links for transmission of at least a second packet, with the first and second packets encoded in different respective tiers of the two-tier signal.
    Type: Grant
    Filed: May 21, 2008
    Date of Patent: April 3, 2012
    Assignee: Alcatel Lucent
    Inventors: Li Li, Harish Viswanathan, Ramachandran Ramjee
  • Publication number: 20120026992
    Abstract: One or more mobile devices and a cloud server computing device are utilized to provide Internet access to one or more client computing devices. One of the clients is designated as a Wi-Fi access point. The Wi-Fi access point implements a reverse-infrastructure Wi-Fi mode which tethers available mobile devices and other clients to the access point. The cloud server periodically computes an optimal number of the mobile devices to be used for data striping, and transmits a webpage to a requesting client by striping data associated with the webpage across the optimal number of the mobile devices.
    Type: Application
    Filed: July 29, 2010
    Publication date: February 2, 2012
    Applicant: MICROSOFT CORPORATION
    Inventors: Vishnu Navda, Ramachandran Ramjee, Venkata N. Padmanabhan, Ashish Sharma
  • Publication number: 20110317631
    Abstract: A method scheduling outgoing communication in a mobile device is provided. The method includes receiving a signal quality profile for an area in which the device is located. The method further includes receiving a signal from a user application stored on the device that requests the mobile device to make the outgoing communication. Additionally, the method includes determining a current location, a speed, a direction, and a signal quality associated with the device and determining whether the signal quality is above a certain threshold. If not, the method includes predicting a future time at which the signal quality will be above the threshold based at least on the current location, the speed, the direction, the signal quality, and the signal quality profile. Finally, the method includes scheduling the outgoing communication from the mobile device at the future time.
    Type: Application
    Filed: June 24, 2010
    Publication date: December 29, 2011
    Applicant: MICROSOFT CORPORATION
    Inventors: Vishnu Navda, Ramachandran Ramjee, Aaron Schulman, Venkata N. Padmanabhan, Kamal Jain
  • Publication number: 20110314121
    Abstract: A method for managing data communication of a mobile device in a mobile network is provided. The method may include receiving a request, at a cloud proxy, to retrieve Internet data from the Internet. The request may originate from an application, and the Internet data may have a plurality unique objects. The method may also include aggregating the Internet data and two or more of the unique objects from the Internet. Furthermore, the method may include forwarding the Internet data and the two or more unique objects to the mobile device in one transmission.
    Type: Application
    Filed: June 16, 2010
    Publication date: December 22, 2011
    Applicant: MICROSOFT CORPORATION
    Inventors: Vishnu Navda, Ramachandran Ramjee, Venkata N. Padmanabhan, Ashish Sharma
  • Patent number: 8068408
    Abstract: A SoftRouter architecture deconstructs routers by separating the control entities of a router from its forwarding components, enabling dynamic binding between them. In the SoftRouter architecture, control plane functions are aggregated and implemented on a few smart servers which control forwarding elements that are multiple network hops away. A dynamic binding protocol performs network-wide control plane failovers. Network stability is improved by aggregating and remotely hosting routing protocols, such as OSPF and BGP. This results in faster convergence, lower protocol messages processed, and fewer route changes following a failure. The SoftRouter architecture includes a few smart control entities that manage a large number of forwarding elements to provide greater support for network-wide control. In the SoftRouter architecture, routing protocols operate remotely at a control element and control one or more forwarding elements by downloading the forwarding tables, etc. into the forwarding elements.
    Type: Grant
    Filed: June 8, 2005
    Date of Patent: November 29, 2011
    Assignee: Alcatel Lucent
    Inventors: Furquan Ahmed Ansari, Martin Havemann, Tirunell V. Lakshman, Thyagarajan Nandagopal, Ramachandran Ramjee, Thomas Y. Woo
  • Publication number: 20110282932
    Abstract: An end host redundancy elimination system and method to provide redundancy elimination as an end system service. Embodiments of the system and method use optimization techniques that reduce server central processing unit (CPU) load and memory footprint as compared to existing approaches. For server storage, embodiments of the system and method use a suite of highly-optimized data structures for managing metadata and cached payloads. An optimized asymmetric max-match technique exploits the inherent structure in data maintained at the server and client and ensures that client processing load is negligible. A load-adaptive fingerprinting technique is used that is much faster than current fingerprinting techniques while still delivering similar compression. Load-adaptive means that embodiments of the fingerprinting technique can adapt CPU usage depending on server load.
    Type: Application
    Filed: May 17, 2010
    Publication date: November 17, 2011
    Applicant: Microsoft Corporation
    Inventors: Ramachandran Ramjee, Bhavish Aggarwal, Pushkar Chitnis, George Varghese, Ashok Anand, Chitra Muthukrishnan, Athula Balachandran
  • Patent number: 8042017
    Abstract: The present invention demonstrates how network-coding can be applied to a deterministic broadcast approach, resulting in significant reductions in the number of transmissions in the network. We propose two algorithms, that rely only on local two-hop topology information and make extensive use of opportunistic listening to reduce the number of transmissions: 1) a simple XOR-based coding algorithm and 2) a Reed-Solomon based coding algorithm that determines the optimal coding gain achievable for a coding algorithm that relies only on local information.
    Type: Grant
    Filed: April 24, 2007
    Date of Patent: October 18, 2011
    Assignee: Alcatel Lucent
    Inventors: Milind M Buddhikot, Li Li, Scott C Miller, Ramachandran Ramjee
  • Publication number: 20110231680
    Abstract: Energy saving virtualization technique embodiments are presented that save energy by virtualizing a network-connected client computer's computing session (or a part thereof) as a virtual machine (VM) and then migrating it between the client computer and a VM server, depending on whether the computing session is active or idle. The client computer VM is migrated to the VM server when the client computer is deemed to be idle, and the VM is migrated back when the client computer is deemed to have re-entered an active condition. When the VM has been migrated away from the client computer and is residing on the VM server, the client computer is put into a sleep mode, thereby saving energy. However, the user's computing session remains alive on the VM server so that ongoing network connections and other activity are not disturbed.
    Type: Application
    Filed: March 22, 2010
    Publication date: September 22, 2011
    Applicant: Microsoft Corporation
    Inventors: Venkata N. Padmanabhan, Ramachandran Ramjee, Tathagata Das, Pradeep Padala
  • Publication number: 20110211517
    Abstract: A “Wi-Fi Multicaster” provides a practical and efficient Wi-Fi multicast system for environments having potentially large numbers of Wi-Fi clients. Significantly, the Wi-Fi Multicaster does not require any changes to the 802.11 protocol, or to the underlying Wi-Fi infrastructure. In various embodiments, the Wi-Fi Multicaster uses pseudo-broadcast, and augments it with destination control, association control and optional proactive FEC (forward error correction) to improve multicast performance. More specifically, the Wi-Fi Multicaster system converts multicast packets to targeted unicast transmissions. To minimize the amount of airtime consumed, the Wi-Fi Multicaster uses destination control in combination with various algorithms for association control. Further, in various embodiments, the Wi-Fi Multicaster includes an adaptive, proactive FEC scheme to reduce overall packet losses. Finally, to overcome the challenges posed by encryption protocols such as 802.
    Type: Application
    Filed: February 26, 2010
    Publication date: September 1, 2011
    Applicant: MICROSOFT CORPORATION
    Inventors: Thomas Moscibroda, Vishnu Navda, Ramachandran Ramjee, Sandeep P. Karanth, Lenin Ravindranath Sivalingam, Jitendra D. Padhye, Ranveer Chandra
  • Patent number: 7975071
    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: Grant
    Filed: January 18, 2008
    Date of Patent: July 5, 2011
    Assignee: Microsoft Corporation
    Inventors: Ramachandran Ramjee, Ranjita Bhagwan, Venkata N. Padmanabhan, Manveer Singh Chawla
  • Patent number: 7944820
    Abstract: The amount of TCP/IP packets which can be sent from an Internet network to a wireless network is maximized by modifying a receive window value of an acknowledgment (ACK) before the ACK is sent on to a source of data packets within the Internet network. The receive window value is modified to take into consideration delay and rate variations which occur in the wireless network.
    Type: Grant
    Filed: February 5, 2008
    Date of Patent: May 17, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Mun Choon Chan, Ramachandran Ramjee