Patents Examined by Toan D. Nguyen
  • Patent number: 7551547
    Abstract: A transmitted symbol matrix and a received symbol vector are transformed based on a non-identity transformation. The non-identity transformation is based on a finite spread of a channel impulse response in a time domain and is usable to improve accuracy of channel estimation in a frequency domain. A transformed channel vector is determined based on the transformed transmitted symbol matrix and the transformed received symbol vector using a channel estimation method. One or more elements in the transformed channel vector are suppressed to at or about zero. The suppressed, transformed channel vector is inverse transformed into an estimated channel vector based on the non-identity transformation.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: June 23, 2009
    Assignee: AT&T Intellectual Property I, L.P.
    Inventor: Arunabha Ghosh
  • Patent number: 7545814
    Abstract: The invention provides a method and system for relieving temporal overload conditions in a router when weighted queues are employed to forward packets to their next destination. Typically, a received packet is mapped to a weighted queue that is associated with the kind of data included in the packet. The invention employs a threshold value to determine when an overloading condition of a weighted queue is so severe that high priority packets are in danger of being dropped. As long as this condition occurs, the invention will remap higher priority packets from a weighted queue associated with the kind of data included in the packets to another weighted queue that is not as loaded and which normally would not be associated with kind of data included in the packets at risk of being dropped.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: June 9, 2009
    Assignee: Nokia Corporation
    Inventor: Outi Hiironniemi
  • Patent number: 7539179
    Abstract: A packet-switched communication system, method for controlling packet-switched calls over such a system, and components of the system are disclosed. In one embodiment, the system provides a scalable implementation for handling H.323 calls. The H.323-required TCP signaling terminations are handled by distributed signaling gateways. Each signaling gateway backhauls the signaling content from these terminations to a central media gateway controller for processing. The media gateway controller uses an efficient gateway control protocol to control media gateways and/or media proxies that actually handle the media bearer channels associated with the backhauled H.323 signaling connections. The H.323 complexity can thus be concentrated in the media gateway controller, without requiring full H.323 functionality at the distributed gateways. Also, because the TCP signaling connections are remote from the media gateway controller, H.323 signaling redundancy can be provided at the media gateway controller.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: May 26, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Randall Baird, Leo Nieuwesteeg
  • Patent number: 7539127
    Abstract: A method for recovering a communication session after failure of an endpoint includes establishing a communication session between a first endpoint and a second endpoint, receiving keep alive signals from the first endpoint, detecting an interruption in the keep alive signals, and transferring the communication session with the second endpoint from the first endpoint to a third endpoint. A network device includes an interface that receives keep alive signals from a first endpoint in a communication with a second endpoint, and also includes a process or service that detects an interruption in the keep alive signals and transfers the communication session with the second endpoint from the first endpoint to a third endpoint.
    Type: Grant
    Filed: December 13, 2001
    Date of Patent: May 26, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Shmuel Shaffer, Arijit Mukherji, Labhesh Patel, Rohit Dewan
  • Patent number: 7539150
    Abstract: A plurality of broadcast messages are sent from at least one node of a plurality of nodes of a network. A node is discovered based on a received message. An entry is stored, wherein the entry corresponds to the node and a timestamp that indicates a time at which the node was last discovered. A notification is made that the node is offline, in response to determining that a predetermined time has elapsed since the timestamp was last updated.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: May 26, 2009
    Assignee: International Business Machines Corporation
    Inventors: John Donald Lauer, Richard Kenneth Martinez, Brian Sean McCain, Amy Lynn Therrien, Yan Xu
  • Patent number: 7532571
    Abstract: Methods and systems allow an application capable of online communication to monitor the availability of different electronic communications sources and provide transition between online and offline operation and between different electronic communications sources. When a change occurs in connectivity source status, such as when the user disconnects from a wireline connection or goes offline or when a connection is otherwise lost due to mechanical failure or loss of wireline or wireless signal or when a reduction in bandwidth or connection speed is detected, the application is automatically transitioned between online and offline status and between different types of connectivity source without user action and without interruption of use of the application. If an online connection may not be obtained via TCP/IP connection, a determination is made as to whether the application and computer operating system are configured for RPC/HTTP connectivity.
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: May 12, 2009
    Assignee: Microsoft Corporation
    Inventors: Michael Price, Alec Dun, Gulsen Demiroz, Ronald Eric Gray, David Raissipour, Aaron Hartwell
  • Patent number: 7512116
    Abstract: A gateway for an internet telephone system manages calls to and from personal computers and enables the personal computers to use the internet telephone system with an IP address assigned by a DHCP server or a private IP address. The gateway has a LAN receiver for processing an incoming call from the Internet or a personal computer, a line transmitter for processing an outgoing call to a telephone according to a request from the LAN receiver, a line receiver for processing an incoming call from a telephone, a LAN transmitter for processing an outgoing call to the Internet or a personal computer according to a request from the line receiver, and a logger for logging information about calls according to requests from the LAN transmitter and line transmitter.
    Type: Grant
    Filed: August 5, 2004
    Date of Patent: March 31, 2009
    Assignee: Fujitsu Limited
    Inventor: Hitoshi Ohura
  • Patent number: 7440392
    Abstract: A deinterleaver module in an OFDM wireless transceiver includes partitioned memory banks for storage of code word fragments from an interleaved data stream, each code word fragment associated with a prescribed subcarrier frequency. Each code word fragment includes a prescribed number of code word bits based on a prescribed modulation of the interleaved data stream, and the code word bits for each code word fragment are written into respective selected locations of the corresponding memory bank based on the prescribed modulation and the corresponding prescribed subcarrier frequency. The deinterleaver module outputs deinterleaved data from the memory banks based on parallel output of the respective stored code word bits from a selected address of the memory banks.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: October 21, 2008
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Chien-Meen Hwang, Peter Chan, Howard Hicks, Chih (Rex) Hsueh, Liping Zhang
  • Patent number: 7436757
    Abstract: Methods of improving channel estimation are described, in which pilot symbols are inserted into orthogonal frequency division multiplexing (OFDM) frames at an OFDM transmitter having at least one transmitting antenna, wherein for the or each antenna, historical data regarding channel conditions is obtained so that the scattered pilot symbols are inserted in a scattered pattern dependent upon said historical data. Alternatively, or in addition, an adaptive channel estimation filter is used whose parameters are selected according to analysis of historical data regarding channel conditions.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: October 14, 2008
    Assignee: Nortel Networks Limited
    Inventors: Keith S Wilson, D. Damian N. Bevan
  • Patent number: 7433361
    Abstract: A method entails wirelessly communicating information from a bidirectional high speed data modem/router in a housing via an Ethernet connection on a first radio transceiver communicating with a second radio transceiver at a customer's premises, wherein the housing connects to a supporting strand that supports a coaxial cable carrying a RF spectrum signal and AC power is described herein. A method entails wirelessly communicating information from a bidirectional high speed data cable modem via an Ethernet connection using a first radio transceiver in a housing to communicate with a number of electronic devices with radio transceivers.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: October 7, 2008
    Inventor: Mark Jeffrey Smith
  • Patent number: 7430223
    Abstract: A computing device has a plurality of subsystems located in subsections that are moveable with respect to each other. Communication between the subsections is accomplished with wireless transceivers transmitting over the air gap interface separating the subsections. Data from multiple communicating subsystems in the subsections is multiplexed into a single data stream and encoded into the communication protocol of the wireless transceivers. The encoded data stream is transmitted to a compatible transceiver where it is decoded. The decoded data stream is demultiplexed into individual data streams for each of the communicating subsystems. The wireless transceivers include multiple communication protocols and transmission frequencies from radio frequencies to optical frequencies. Optical fibers, transmission lines or waveguides may be used to transmit signals within each subsection depending on the wireless technology and protocol.
    Type: Grant
    Filed: August 28, 2002
    Date of Patent: September 30, 2008
    Assignee: Advanced Micro Devices, Inc.
    Inventors: David W. Smith, Garth Hillman, Clark L. Buxton
  • Patent number: 7382782
    Abstract: A network device includes multiple packet processing engines implemented in parallel with one another. A spraying component distributes incoming packets to the packet processing engines using a spraying technique that load balances the packet processing engines. In particular, the spraying component distributes the incoming packets based on queue lengths associated with the packet processing engines and based on a random component. In one implementation, the random component is a random selection from all the candidate processing engines. In another implementation, the random component is a weighted random selection in which the weights are inversely proportional to the queue lengths.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: June 3, 2008
    Assignee: Juniper Networks, Inc.
    Inventors: Dennis C. Ferguson, Chi-Chung Chen, Thomas M. Skibo
  • Patent number: 7190667
    Abstract: Some embodiments of the present invention include data network comprising a host system having a host-fabric adapter; at least one remote system; a switch fabric which interconnects said host system via said host-fabric adapter to said remote system along different physical links for data communications; and at least one communication port provided in the host-fabric adapter of the host system including a set of transmit and receive buffers capable of sending and receiving data packets concurrently via respective transmitter and receiver at an end of a physical link, via the switched fabric, and a flow control mechanism utilized to prevent loss of data due to receive buffer overflow at the end of the physical link. Other embodiments are described and claims.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: March 13, 2007
    Assignee: Intel Corporation
    Inventors: Dean S. Susnow, Richard D. Reohr, Jr.
  • Patent number: 7173941
    Abstract: An apparatus and method are detailed that allows for improved detection of communication devices and/or doublers in an associated physical communication links, in particular on HDSL communication links. The improved device apparatus and method additionally allows for the communication device to identify when all devices on a communication link have been detected and prevent premature termination of a discovery process. The improved device apparatus and method also allows the avoidance of improper detection of communication devices or doublers due to corrupted discovery response messages.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: February 6, 2007
    Assignee: ADC DSL Systems, Inc.
    Inventor: Raymond Diaz
  • Patent number: 7170905
    Abstract: The invention relates to an enhanced ADSL Data Network (ADN) with vertical services capabilities. In general, vertical services capabilities are data services offered directly from a central office to an end user, without compromising the integrity of the user's guaranteed bit rate to the Internet through the ADN. One such vertical service is content downloadable at a high data rate from a content server located in or proximate to a central office that serves the end user. The content of the local server is updated and upgraded periodically and systematically from a central content server that distributes content to a number of remote central offices. The content is distributed between the central content server and the respective local content servers using available bandwidth, that is to say bandwidth on at least certain network links that is unused by subscriber traffic.
    Type: Grant
    Filed: April 17, 2001
    Date of Patent: January 30, 2007
    Assignee: Verizon Communications Inc.
    Inventors: Robert T. Baum, Eric A. Voit
  • Patent number: 7154904
    Abstract: A time slot management method for use in a time division multiple access network. The time division multiple access network includes a main station (MS) coupled to each of a plurality of substations (S1, S2, S3, . . . , S15, S16) via the cascade connection of a common transmission link (Lc) and an individual user link (L1, L2, L3, . . . , L15, L16). The management method includes broadcasting substation identities (TEA1, TEA12, TEA16, TEA3, TEA7, . . . ) in downstream information packets from the main station (MS) to the plurality of substations (S1, S2, S3, . . . , S15, S16) to allow each one of the plurality of substations (S1, S2, S3, . . . , S15, S16) upon detection of its own substation identity to transfer a predetermined amount of upstream information packets in predetermined upstream timeslots to the main station (MS). The time slot management method additionally includes embedding at least part of the substation identities (TEA12, TEA3, TEA7, . . .
    Type: Grant
    Filed: March 24, 2003
    Date of Patent: December 26, 2006
    Assignee: Alcatel
    Inventors: Jan Lieven Bert De Groote, Ingrid Zulma Benoit Van De Voorde
  • Patent number: 7035281
    Abstract: A wireless provisioning device (WPD) is a computer data traffic management system capable of routing TCP/IP traffic using 2.4 Ghz equipment. This WPD is to be strategically placed in logical segment regions within a wireless network to facilitate data traffic management. This device acts to provide connectivity between wireless backbone access points. The device may also be located within customer local area network (LAN) while providing connectivity to a wide area network (WAN). The wireless device has seven total wireless segments. The wireless device is capable of filtering IP addresses, controlling firewall and/or router and/or bridge. The wireless provisioning device increases effective throughput of TCP/IP traffic over the WAN or LAN while providing for secure management and greater connectivity.
    Type: Grant
    Filed: September 13, 2000
    Date of Patent: April 25, 2006
    Assignee: WP Media, Inc.
    Inventors: Anthony C. Spearman, Andrew E. Tompkins
  • Patent number: 6999479
    Abstract: An apparatus comprising one or more nodes. The apparatus may be configured to transport one or more packets within a frame. The one or more nodes may be configured to add and/or drop at least one of the one or more packet from the frame.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: February 14, 2006
    Assignee: Cypress Semiconductor Corp.
    Inventor: Pankaj K. Jha
  • Patent number: 6996116
    Abstract: An interface module is provided for connecting a data communications link to a switching node, comprising a plurality of other interface modules, of a data communications network. The interface module has at least one external port for connection to a data communications link, and a plurality of internal ports for connection to respective internal ports of the switching node. A link interface is connected to the external port for processing inbound and outbound data. A switch circuit is connected between the link interface and the internal ports of the module for transmission of data between the internal ports and to the link interface. The module includes a controller for controlling routing of data via the internal ports in accordance with an intra-node routing protocol. Switching nodes comprising a plurality of interface modules, and optionally one or more switching modules, are provided.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: February 7, 2006
    Assignee: International Business Machines Corporation
    Inventors: Ton Engbersen, Ronald P. Luijten
  • Patent number: 6987775
    Abstract: A variable size first in first out (FIFO) memory is provided. The variable size FIFO memory may include head and tail FIFO memories operating at a very high data rate and an off chip buffer memory. The off chip buffer memory may be, for example, of a dynamic RAM type. The off chip buffer memory may temporarily store data packets when both head and tail FIFO memories are full. Data blocks of each of the memories may be the same size for efficient transfer of data. After a sudden data burst which causes memory overflow ceases, the head and tail FIFO memories return to their initial functions with the head FIFO memory directly receiving high speed data and transmitting it to various switching element and the tail FIFO memory storing temporary overflows of data from the head FIFO memory.
    Type: Grant
    Filed: August 15, 2001
    Date of Patent: January 17, 2006
    Assignee: Internet Machines Corp.
    Inventor: Chris Haywood