Patents by Inventor Prathima Agrawal

Prathima Agrawal 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: 7002936
    Abstract: A technique for assigning an address (“shadow address”) to a mobile station that is compatible with the layer-2 address on the wireline network which serves the mobile station. The shadow address is then used as a wireline identifier for the destination address for frames ultimately destined for the mobile station. The shadow address is stored in a watch list for serving base stations, and any base station receiving a frame with a shadow address in its watch list process the frame to forward it the to mobile station. In this way, the shadow address facilitates carrying out soft handoff and smooth handoff.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: February 21, 2006
    Assignees: Telcordia Technologies, Inc., Toshiba America Research, Inc.
    Inventors: Prathima Agrawal, Jyh-Cheng Chen, Tao Zhang
  • Patent number: 6999434
    Abstract: Method, system, and circuitry for successfully completing soft handoff in an Internet Protocol (IP) based autonomous base station wireless Code Division Multiple Access network, wherein processing is done at the serving base station so that target base stations need only set up the channel for transmitting the copied data needed for soft handoff. Concomitant circuitry comprises packet data multiplexers/assemblers and demultiplexers/de-assemblers for performing cross-layer switching. Data packets are sent by a serving base station to a mobile unit while the mobile is in a soft handoff region. The serving base station also sends copies of the data packets to target base stations, the target base stations in turn relay these data packets to the mobile. The mobile synchronizes the copies of the data packets received and combines the packets to recover the data.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: February 14, 2006
    Assignees: Telcordia Technologies, Inc., Toshiba America Research, Inc.
    Inventors: Prathima Agrawal, Shinichi Baba, Tadahiko Maeda, Tao Zhang
  • Patent number: 6992995
    Abstract: Methods and systems are provided for facilitating intra-domain mobility. A first network or domain includes a home agent or SIP proxy of a mobile node. A second network includes two or more subnetworks and at least one mobility agent (MA). Each subnetwork includes an associated subnet agent. To communicate, the mobile node first registers with a subnet agent, receives a local care-of-address and a global care-of-address, and then registers with an MA. The mobile node may then provide the global care-of-address to the home agent. The local care-of-address may enable communication with the mobile node without determining a specific route to the mobile node. The global care-of-address received from the subnet agent may include the address of the MA.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: January 31, 2006
    Assignees: Telcordia Technologies, Inc., University of Texas
    Inventors: Prathima Agrawal, Subir Das, Sajal Das, Archan Misra
  • Patent number: 6992994
    Abstract: Methods and systems are provided for facilitating intra-domain mobility. A first network or domain includes a home agent or SIP proxy of a mobile node. A second network includes two or more subnetworks and at least one dynamic tunneling agent (DTA). Each subnetwork includes an associated subnet agent. To communicate, the mobile node first registers with a subnet agent, receives a local care-of-address and a global care-of-address, and then registers with a DTA. The local care-of-address received from the subnet agent may enable communication with the mobile node without determining a specific route to the mobile node. The global care-of-address received from the subnet agent may include the address of the DTA with which to register. On registering with the DTA, the DTA may provide the mobile node with a unique, globally reachable global care-of-address, which the mobile node may then forward to a home agent, SIP proxy, or a correspondent node.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: January 31, 2006
    Assignees: Telcordia Technologies, Inc., University of Texas
    Inventors: Subir Das, Archan Misra, Anthony Mcauley, Ashutosh Dutta, Prathima Agrawal, Sajal Das
  • Publication number: 20060009232
    Abstract: A system and method for equalizing traffic between antenna beams is described. Aspects of the system and method may vary the beam widths to attempt to equalize traffic based on non-real-time communications and/or non-real-time communications.
    Type: Application
    Filed: July 7, 2004
    Publication date: January 12, 2006
    Applicants: Toshiba America Research Inc. (TARI), Telcordia Technologies, Inc.
    Inventors: Faramak Vakil, David Famolari, Kamesh Medepalli, Prathima Agrawal, Toshikazu Kodama, Shuichi Obayashi, Ryoko Matsuo
  • Patent number: 6965584
    Abstract: A method and system for dynamic forward assignment of IP addresses in a wireless network wherein a serving base station requests IP addresses of it neighboring cells. The serving base station then provides the requested IP addresses to the mobile stations it serves based on whether the mobile station will be entering a particular neighboring cell. Immediately upon entering the neighboring cell the mobile station establishes over the air communications with the neighboring cell's base station using one of the requested addresses. In another embodiment of the present invention each mobile unit is responsible for attaining IP addresses from the base stations of neighboring cells. Accordingly, the base stations serve as relay points for the IP address requests from the mobile unit to an address server.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: November 15, 2005
    Assignees: Telcordia Technologies, Inc., Toshiba America Research, Inc.
    Inventors: Prathima Agrawal, Toshikazu Kodama, Faramak Vakil, Tao Zhang
  • Publication number: 20050163079
    Abstract: Systems and methods are described for secure and seamless roaming between internal and external networks. Double and triple tunnels may be used to connect a mobile node to a correspondent host. A mobile node may include the ability to connect to two networks simultaneously to enable seamless roaming between networks.
    Type: Application
    Filed: July 21, 2004
    Publication date: July 28, 2005
    Applicants: Toshiba America Research Inc. (TARI), Telcordial Technologies, Inc.
    Inventors: Kenichi Taniuchi, Tao Zhang, Prathima Agrawal, Ashutosh Dutta, Shinichi Baba, Kensaku Fujimoto, Yasuhiro Katsube, Toshikazu Kodama, Yoshihiro Ohba, Sunil Madhani
  • Publication number: 20050147084
    Abstract: This document describes Toll Free IP (TIP), a business model and its enabling methods to provide no-charge-to-user (“toll-free”) connectivity through IP-based access networks (e.g., public wireless hotspot networks based on IEEE 802.11), which may be operated by different network operators. With TIP, the use of networks to communicate with a toll-free IP destination will be paid by the owner of the toll-free IP destination. A toll-free IP destination can be identified in many ways, e.g., by a toll-free IP address, toll-free Internet Domain Name, a toll-free Universal Resource Identifier or Universal Resource Locator. TIP enables a user to use networks without prior service subscriptions with network or service providers and without any special terminal software or hardware for gaining permission to use a network. It allows users to use more access networks, i.e., larger “footprints”, than any individual network operator or aggregator can provide.
    Type: Application
    Filed: December 9, 2004
    Publication date: July 7, 2005
    Inventors: Tao Zhang, Miriam Tauil, Sunil Madhani, Prathima Agrawal, Toshikazu Kodama
  • Patent number: 6795709
    Abstract: Method and apparatus for dynamically allocating IP addresses in a wireless IP network. IP address servers determine the requisite IP address pools and guard bands for individual network cells to guarantee fair access to the network and facilitate handoff host handoff from a prior cell to a new cell. IP address servers also prioritize handoff and resident hosts that request an IP address from the IP address server. In particular, IP address servers assign a higher priority to handoff hosts over resident hosts that request an IP address from an IP address server in order to maintain a preestablished handoff host network connection instead of dropping a handoff host connection in favor of a new resident host network connection. Finally, each cell is allocated a minimum number of IP addresses to ensure a certain level of fair access to the network regardless of the cell wherein a handoff or resident host resides.
    Type: Grant
    Filed: April 23, 2001
    Date of Patent: September 21, 2004
    Assignee: Telcordia Technologies, Inc.
    Inventors: Prathima Agrawal, David Famolari, Tao Zhang
  • Patent number: 6788660
    Abstract: Active packets are utilized by a mobile terminal in a wireless network to set-up a wireless call via a signaling process, and for mobility management via a mobility process as the mobile terminal moves from one cell to another in a subnet. Active packets instantiate an agent in the fixed network to handle signaling between the mobile terminal and the fixed network, and then instruct the agent to negotiate setup of an open channel between the mobile terminal and the destination device. Moreover, active packets foster the handoff of the mobile terminal as the terminal moves from one cell to another in a subnet. Finally, the signaling process and mobility process are coordinated so that lost active packets are mitigated during roaming by the mobile terminal.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: September 7, 2004
    Assignee: Telcordia Technologies, Inc.
    Inventors: Prathima Agrawal, Jyh-Cheng Chen
  • Publication number: 20040165562
    Abstract: Aspects of the invention provide a method and system for managing or coordinating data transmission in a Local Area Network (LAN) such that Quality of Service (QoS) concerns are met. A LAN resource manager (LRM) is provided for managing the LAN resources by providing solutions for providing users with several levels of QoS. Once the LRM admits a user at a certain QoS level, the level is assured within the LAN for as long as the user is in the LAN. A user may submit a request to transmit data to the LRM. The LRM may determine if time allocation is possible and allocate the time slots for data transmission. The LRM may send time slot allocation information to an Access Server in a LAN, which may inform the user of the time slot allocation and prepare a queue according to the slot allocation information.
    Type: Application
    Filed: February 24, 2003
    Publication date: August 26, 2004
    Applicants: Toshiba America Research Inc., Telcordia Technologies
    Inventors: Moncef Elaoud, Abhrajit Ghosh, Ravichander Vaidyanathan, Prathima Agrawal, Toshikazu Kodama, Yasuhiro Katsube
  • Patent number: 6775253
    Abstract: Active packets are utilized by a mobile terminal in a wireless network to set-up a wireless call via a signaling process, and for mobility management via a mobility process as the mobile terminal moves from one cell to another in a subnet. Active packets instantiate an agent in the fixed network to handle signaling between the mobile terminal and the fixed network, and then instruct the agent to negotiate setup of an open channel between the mobile terminal and the destination device. Moreover, active packets foster the handoff of the mobile terminal as the terminal moves from one cell to another in a subnet. Finally, the signaling process and mobility process are coordinated so that lost active packets are mitigated during roaming by the mobile terminal.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: August 10, 2004
    Assignee: Telcordia Technologies, Inc.
    Inventors: Prathima Agrawal, Jyh-Cheng Chen
  • Patent number: 6721331
    Abstract: A method and apparatus provide decentralized prioritized scheduling of wireless access in a carrier sense multiple access with collision avoidance (CSMA/CA) wireless local area network (LAN) is presented. Prior to and during data packet transmissions, a device station in the CSMA/CA wireless LAN continuously monitors transmission traffic in the bandwidth medium of the wireless LAN to determine whether the delay associated with pre-transmission of a data packet, due to the collision avoidance protocol in the CSMA/CA wireless LAN, exceeds the time frame in which the device station necessarily must transmit the data packet. If the delay is too great for the type of data packet to be transmitted, the device station decreases the possible range of the back-off duration of the collision avoidance protocol. Thus, the station device can increase its transmission priority by decreasing the randomly selected back-off duration range of values.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: April 13, 2004
    Assignee: AT&T Corp.
    Inventors: Prathima Agrawal, Parameswaran Ramanathan, Cormac John Sreenan
  • Publication number: 20040024901
    Abstract: Methods and systems are provided for facilitating intra-domain mobility. A first network or domain includes a home agent or SIP proxy of a mobile node. A second network includes two or more subnetworks and at least one mobility agent (MA). Each subnetwork includes an associated subnet agent. To communicate, the mobile node first registers with a subnet agent, receives a local care-of-address and a global care-of-address, and then registers with an MA. The mobile node may then provide the global care-of-address to the home agent. The local care-of-address may enable communication with the mobile node without determining a specific route to the mobile node. The global care-of-address received from the subnet agent may include the address of the MA.
    Type: Application
    Filed: April 12, 2001
    Publication date: February 5, 2004
    Inventors: Prathima Agrawal, Subir Das, Sajal Das, Archan Misra
  • Patent number: 6628943
    Abstract: Active packets are utilized by a mobile terminal in a wireless network to set-up a wireless call via a signaling process, and for mobility management via a mobility process as the mobile terminal moves from one cell to another in a subnet. Active packets instantiate an agent in the fixed network to handle signaling between the mobile terminal and the fixed network, and then instruct the agent to negotiate setup of an open channel between the mobile terminal and the destination device. Moreover, active packets foster the handoff of the mobile terminal as the terminal moves from one cell to another in a subnet. Finally, the signaling process and mobility process are coordinated so that lost active packets are mitigated during roaming by the mobile terminal.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: September 30, 2003
    Assignee: Telcordia Technologies, Inc.
    Inventors: Prathima Agrawal, Jyh-Cheng Chen
  • Patent number: 6606661
    Abstract: The present invention discloses a method of improving the performance of a server enabled to permit connections to clients to persist for a duration equal to a timer value, such as Web servers utilizing HTTP/1.1. In accordance with an embodiment of the present invention, the server estimates the load on the server and uses the estimate to modify the timer value. The timer value can be chosen to balance the need to increase the throughput as seen by the clients and the server need to service the largest possible number of clients without running out of resources. The timer value can be set to a longer value when the server load is light and a shorter value when the server load is heavy. In a preferred embodiment of the present invention, the server dynamically selects the largest timer that guarantees that the server does not run out of resources under the current measured load.
    Type: Grant
    Filed: December 23, 1999
    Date of Patent: August 12, 2003
    Assignee: AT&T Corp.
    Inventors: Prathima Agrawal, Moncef Elaoud, Parameswaran Ramanathan, Cormac John Sreenan
  • Publication number: 20030142647
    Abstract: Method and system for discrete soft handoff of mobile terminals in a wireless CDMA network. Mobile terminal-base station channels perform soft handoff in a discrete fashion by predicting which reserved channels will be “strong” and “weak” for CDMA data frame transmission. At least one of the strong channels is included in the active set of handoff legs used to transmit the CDMA data frame, and the invention transmits the CDMA data frame only through channels within the active set.
    Type: Application
    Filed: January 31, 2002
    Publication date: July 31, 2003
    Inventors: Prathima Agrawal, David Famolari
  • Publication number: 20030142642
    Abstract: The transmission of unnecessary assignment and validation information to mobile terminals in wireless IP networks is automatically blocked. Assignment and validation information originating with a mobile terminal is discarded by a base station if the information is not directly received by the base station from a mobile terminal. Assignment and validation information originating with an IP address server is broadcast only to those mobile terminals awaiting assignment or validation information using a local broadcast IP address. The validation and assignment is automatically begun once a mobile terminal enters a new subnet by resetting the mobile terminal's IP address to the broadcast address for assignment and validation requests and then broadcasting validation and, if necessary, assignment requests to the wireless IP network.
    Type: Application
    Filed: January 31, 2002
    Publication date: July 31, 2003
    Inventors: Prathima Agrawal, Jyh-Cheng Chen, Tao Zhang
  • Publication number: 20030108008
    Abstract: An arrangement including a scannable matrix for predicting the occurrence of a future collision of frequency hops of the channel hopping patterns on the respective activated first paths of a Bluetooth packet transmission system is described. A first coordinate of the matrix defines columns representative of a selectable window of N successive future time slots of the channel hopping patterns, and a second coordinate of the matrix defines rows each exhibiting the successive frequency hops of the patterns segments transmitted on a separate one of the activated channels during such window. The first coordinate is scanned to detect the occurrence, if any, of identical frequency hops appearing at an intersection of the then-scanned column and at least a pair of the rows.
    Type: Application
    Filed: December 10, 2001
    Publication date: June 12, 2003
    Inventors: Prathima Agrawal, David Famolari
  • Publication number: 20030108062
    Abstract: A multiple-interface radio terminal is provided with facilities which dynamically assign a stream of packet data to be transmitted to a selected one of a plurality of interface(s). The interfaces respectively support channels that share a common frequency spectrum but that operate with different transmission protocols, for example the Bluetooth and 802.11 protocols. The terminal is provided with an interface manager that periodically transmits query signals to the respective channels to obtain and store refreshable inputs representative of a selected transmission condition(s) on such channels. Upon the occurrence of a connection request at the terminal, the interface manager compares the latest stored samples from the respective channels with a reference metric to generate an indication which represents the relative states of the channels with regard to the selected transmission condition.
    Type: Application
    Filed: December 10, 2001
    Publication date: June 12, 2003
    Inventors: Prathima Agrawal, David Famolari