Patents by Inventor Ramanathan T. Jagadeesan

Ramanathan T. Jagadeesan 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: 7383046
    Abstract: According to a particular embodiment, a method for assisting in a handoff is provided that includes receiving signaling from one or more access points, which may transmit information to a mobile station. The information may be used to execute a handoff from an enterprise network to a cellular network or from the cellular network to the enterprise network.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: June 3, 2008
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Chol Su Kang, Bich T. Nguyen, David S. Stephenson, Richard D. Rebo
  • Patent number: 7373413
    Abstract: Devices and methods are provided for minimizing the startup delay of streaming media transmitted through networks. A server maintains a portion of the media stream stored in an initial burst transmit buffer. At startup, the stored portion is transmitted at a rate higher than the fixed frame rate, exploiting the full available bandwidth. The initial burst transmission fills up the de-jitter receive buffer at the receiving end faster, thereby shortening the startup delay. Then transmission is switched to the regular rate, from the regular buffer. A variable bit rate transcoder is optionally used for the data of the initial transmission. The transcoder diminishes the size of these frames, so they can be transmitted faster. This shortens the start up delay even more. A receiver has a buffer with a fill level started at a value lower than a final value. This triggers the beginning of play out faster, further shortening the delay time.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: May 13, 2008
    Assignee: Cisco Technology, Inc.
    Inventors: Bich Nguyen, Ilya Slain, Kevin J. Connor, Luke K. Surazski, Ramanathan T. Jagadeesan
  • Patent number: 7328015
    Abstract: A mobile device supports concurrent registrations of different wireless personalities with one or more service provider networks. Potentially using a single wireless interface, the mobile device can register and maintain multiple personalities and monitor for notifications targeted to any one of these personalities.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: February 5, 2008
    Assignee: Cisco Technology, Inc.
    Inventors: Michael A. Ramalho, Ramanathan T. Jagadeesan, Bich Tu Nguyen
  • Patent number: 7319864
    Abstract: A system for providing a single number reachability solution for communications with a desktop telephone and a cellular telephone includes a mobility application coupled to a call management application. The call management application can associate a telephone number with a desktop telephone and a first communication port, receive a first telephone call initiated by a remote device and directed to the telephone number, and offer the first telephone call to the desktop telephone and to the first communication port. The mobility application can associate the first communication port with a cellular telephone, obtain a second communication port from multiple available communication ports in response to the offer, and place a second telephone call to the cellular telephone using the second communication port.
    Type: Grant
    Filed: November 15, 2004
    Date of Patent: January 15, 2008
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Christopher E. Pearce
  • Patent number: 7310527
    Abstract: A method for handing off a call between networks includes monitoring a quality of a first link between a mobile station and a wireless local area network (WLAN) when the mobile station is actively connected with the WLAN on a call and monitoring a quality of a second link between the mobile station and a cellular network when the mobile station is actively connected with the WLAN on the call. The method also includes handing off the call from the WLAN to the cellular network when the quality of the first link is less than a handoff trigger threshold for a drop count duration and when the quality of the second link is greater than a minimum cellular link quality threshold.
    Type: Grant
    Filed: May 30, 2006
    Date of Patent: December 18, 2007
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Bich Tu Nguyen
  • Patent number: 7299049
    Abstract: Devices, softwares methods hand off a live call from an original leg of a first modality (such as Circuit Switched Voice) to an alternate leg of another modality (such as Voice over Internet Protocol). An original leg of a call is established using the first modality. Then the alternate leg of the call is established using the second modality, while the first leg is still established. Then the call is handed off from the original leg to the alternate leg, while the connection is active.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: November 20, 2007
    Assignee: Cisco Technology, Inc.
    Inventor: Ramanathan T. Jagadeesan
  • Patent number: 7283823
    Abstract: A mobile station includes a first wireless interface that can couple to a first wireless network, a second wireless interface that can couple to a second wireless network, and a controller. The controller can negotiate a first wireless link with the first wireless network using the first wireless interface and establish a communication session with a remote device using the first wireless link. The controller can also detect a session handoff trigger, negotiate a second wireless link with the second wireless network using the second wireless interface in response to the session handoff trigger, and invoke a private branch exchange feature to transfer the communication session from the first wireless link to the second wireless link.
    Type: Grant
    Filed: September 10, 2004
    Date of Patent: October 16, 2007
    Assignee: Cisco Technology, Inc.
    Inventors: Christopher E. Pearce, Ramanathan T. Jagadeesan, Bich T. Nguyen
  • Patent number: 7251241
    Abstract: Source devices, softwares and methods are provided for predicting at a transmitting source how well a specific encoded frame, relative to other frames in a stream, would be reconstructed if it were not available for eventual playout at a receiving destination. If poorly, then the specific encoded frame is packetized and transmitted advantageously with respect to other packets in a stream. The transmitted stream will have higher jitter. Predicting is performed at the source by synthesizing a replicated frame, which emulates how the specific frame would be reconstructed at the destination. Then the replicated frame is compared with the decoded specific frame. The eventual playout will have a higher fidelity to the original, since reconstructed from more critical frames.
    Type: Grant
    Filed: August 21, 2002
    Date of Patent: July 31, 2007
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Luke Surazski
  • Patent number: 7227853
    Abstract: A method is provided that includes receiving a request from a communication device to establish a communication session with a mobile station, the mobile station being operable to roam between a private and a public network. The mobile station is signaled via a cellular data network that a call is being initiated for the mobile station. Signaling information may be exchanged with a voice gateway such that one or more voice circuits are established. A signaling pathway may be established between an Internet protocol private branch exchange (IP PBX) and the mobile station via the cellular data network. The establishment of the signaling pathway is substantially concurrent with the establishment of one or more of the voice circuits. One or more features associated with a private network are delivered to the mobile station during the communication session as an end user moves between the public and private networks.
    Type: Grant
    Filed: June 16, 2006
    Date of Patent: June 5, 2007
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Bich T. Nguyen, Kamaldip Toor, Sudhakar S. Valluru, Christopher E. Pearce
  • Patent number: 7082301
    Abstract: A method for handing off a call between networks includes monitoring a quality of a first link between a mobile station and a wireless local area network (WLAN) when the mobile station is actively connected with the WLAN on a call and monitoring a quality of a second link between the mobile station and a cellular network when the mobile station is actively connected with the WLAN on the call. The method also includes handing off the call from the WLAN to the cellular network when the quality of the first link is less than a handoff trigger threshold for a drop count duration and when the quality of the second link is greater than a minimum cellular link quality threshold.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: July 25, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Bich Tu Nguyen
  • Patent number: 7076251
    Abstract: A method is provided that includes receiving a request from a communication device to establish a communication session with a mobile station. The request is responded to by signaling the mobile station via a cellular data network that a call is being initiated for the mobile station. Signaling information may be exchanged with a voice gateway such that one or more voice circuits are established to accommodate voice data that may propagate between the communication device and the mobile station. A signaling pathway may be established between an Internet protocol private branch exchange (IP PBX) and the mobile station via the cellular data network. The establishment of the signaling pathway is substantially concurrent with the establishment of one or more of the voice circuits such that one or more features associated with a private network are delivered to the mobile station during the communication session.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: July 11, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Bich T. Nguyen, Kamaldip Toor, Troy M. Trenchard, Sudhakar S. Valluru, Tony T. Wan
  • Patent number: 7068622
    Abstract: A method is provided that includes receiving a request from a communication device to establish a communication session with a mobile station, the mobile station being operable to roam between a private and a public network. The mobile station is signaled via a cellular data network that a call is being initiated for the mobile station. Signaling information may be exchanged with a voice gateway such that one or more voice circuits are established. A signaling pathway may be established between an Internet protocol private branch exchange (IP PBX) and the mobile station via the cellular data network. The establishment of the signaling pathway is substantially concurrent with the establishment of one or more of the voice circuits. One or more features associated with a private network are delivered to the mobile station during the communication session as an end user moves between the public and private networks.
    Type: Grant
    Filed: February 21, 2005
    Date of Patent: June 27, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Bich T. Nguyen, Kamaldip Toor, Sudhakar S. Valluru, Christopher E. Pearce
  • Patent number: 7003298
    Abstract: Devices, softwares methods hand off a live call from an original leg of a first modality (such as Circuit Switched Voice) to an alternate leg of another modality (such as Voice over Internet Protocol). An original leg of a call is established using the first modality. Then the alternate leg of the call is established using the second modality, while the first leg is still established. Then the call is handed off from the original leg to the alternate leg, while the connection is active.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: February 21, 2006
    Assignee: Cisco Technology, Inc.
    Inventor: Ramanathan T. Jagadeesan
  • Patent number: 6999560
    Abstract: A test system measures performance of telephone network echo cancellers using a primary criterion of estimated user annoyance due to audible returned echo. The invention generates live telephone calls, uses real speech samples as stimulus signals and provides tail-circuit emulation using actual measured telephone tail-circuit impulse responses. These features provide better ‘real-life’ test conditions for the echo canceller system under test than current ITU standard test methods. Two methods are employed for echo canceller performance evaluation via metrics of estimated user annoyance due to echo. Energy-based method employs point-by-point comparison of talker speech and talker echo signal energy envelopes and uses variable energy thresholds for estimation of echo audibility. A perceptual-model based method uses a Perceptual Speech Distortion Metric (PSDM), such as ITU P.861, in an unique configuration to estimate user annoyance due to audible echo.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: February 14, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: Kevin J. Connor, Michael E. Knappe, Ramanathan T. Jagadeesan
  • Patent number: 6999417
    Abstract: Devices, software, and methods quantify a burstiness quality of the packet loss in the node of a path. The quantified burstiness becomes a metric for determining the Quality of Service (QoS) offered by a node in retransmitting data through a network. Network routing and rerouting decisions are made according to the improved QoS. The burstiness statistic is determined by counting lengths of episodes of sequentially discarded packets at the node. The burstiness statistic is incorporated as a metric with the other metrics of the QoS of the node.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: February 14, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: Philip R. Graham, Ramanathan T. Jagadeesan, Bich Tu Nguyen
  • Patent number: 6999763
    Abstract: A mobile device supports concurrent registrations of different wireless personalities with one or more service provider networks. Potentially using a single wireless interface, the mobile device can register and maintain multiple personalities and monitor for notifications targeted to any one of these personalities.
    Type: Grant
    Filed: August 14, 2003
    Date of Patent: February 14, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: Michael A. Ramalho, Ramanathan T. Jagadeesan, Bich Tu Nguyen
  • Patent number: 6930982
    Abstract: Devices, software, and methods measure a burstiness of packet loss episodes in transmissions of voice data through networks. At least one burstiness statistic is determined to quantify how the lost packets are distributed with respect to the received packets within the sequence. The burstiness statistic is optionally used to determine a figure of merit, which in turn can be used to give a grade for predicting how well a packet loss concealment scheme will work.
    Type: Grant
    Filed: December 12, 2000
    Date of Patent: August 16, 2005
    Assignee: Cisco Technology, Inc.
    Inventor: Ramanathan T. Jagadeesan
  • Patent number: 6888808
    Abstract: A method is provided that includes receiving a request from a communication device to establish a communication session with a mobile station, the mobile station being operable to roam between a private and a public network. The mobile station is signaled via a cellular data network that a call is being initiated for the mobile station. Signaling information may be exchanged with a voice gateway such that one or more voice circuits are established. A signaling pathway may be established between an Internet protocol private branch exchange (IP PBX) and the mobile station via the cellular data network. The establishment of the signaling pathway is substantially concurrent with the establishment of one or more of the voice circuits. One or more features associated with a private network are delivered to the mobile station during the communication session as an end user moves between the public and private networks.
    Type: Grant
    Filed: September 15, 2003
    Date of Patent: May 3, 2005
    Assignee: Cisco Technology, Inc.
    Inventors: Ramanathan T. Jagadeesan, Bich T. Nguyen, Kamaldip Toor, Sudhakar S. Valluru, Christopher E. Pearce
  • Patent number: 6836804
    Abstract: Devices, software and methods are provided for encoding voice data to conceal packet loss in Voice over Internet Protocol applications. The voice data of each frame is split into two groups, one of a low frequency band and one of a high frequency band. The two groups are transmitted through a network as separate packets. The high frequency group of one frame can be paired with the low frequency group of the next frame.
    Type: Grant
    Filed: October 30, 2000
    Date of Patent: December 28, 2004
    Assignee: Cisco Technology, Inc.
    Inventor: Ramanathan T. Jagadeesan
  • Patent number: 6801622
    Abstract: Devices, software and methods are provided for encoding DTMF signals for telephone connections between digital voice communication systems that use compression, such as wireless connections or network connections. First the twist of the DTMF signals is determined, and then it is determined whether the twist is within a mapped range of a remote decoder. If not, the signal is first balanced to change the twist, and then the balanced signal is encoded.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: October 5, 2004
    Assignee: Cisco Technology, Inc.
    Inventor: Ramanathan T. Jagadeesan