Patents by Inventor Iwao Tada

Iwao Tada 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: 6856594
    Abstract: A method and system including ATM switching equipment provided for switching between a working channel and a protection channel in an ATM network. The method and system include the following processes: In each cell for transmission providing an indication of whether the cell belongs connection currently in a working state via a working channel; cells are duplicated on each connection basis; the duplicated cells are transmitted simultaneously on both a working channel and a protection channel; and valid cells are selected from received cells according to the indication in each cell indicating whether the relevant connection is currently in a working state.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: February 15, 2005
    Assignee: Fujitsu Limited
    Inventors: Naoki Aihara, Hichiro Hayami, Iwao Tada, Tomoyuki Yamaguchi
  • Patent number: 6446146
    Abstract: To reduce a scale of the circuit, a number of the external terminals, processing steps in developing a firmware, and a scale of the firmware, a line terminator provided in a device for terminating SONET/SDH lines, each having a different line speed, terminates plural lines, each having a different line speed, and includes a clock generator generating a clock corresponding to each line speed, a line switching circuit for specifying one of the plural lines, a selector for outputting data of one of the plural lines, which is specified by the line switching circuit, and a common processing circuit for processing data of the one line output from the selector, according to a clock corresponding to the line speed generated in the clock generator.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: September 3, 2002
    Assignee: Fujitsu Limited
    Inventors: Tomoyuki Yamaguchi, Jyoei Kamoi, Iwao Tada
  • Patent number: 6212186
    Abstract: The invention concerns an ATM exchange, and is directed in particular to the provision of a cell bandwidth control apparatus for performing bandwidth control for ATM cells sent from the ATM exchange onto the line side. The cell bandwidth control apparatus includes forced empty cell inserting means for forcibly inserting empty cells in a highway connected to an ATM switch. The forced empty cell inserting means inserts forced empty cells in an outgoing highway leading from the ATM switch to a line adapter and thereby limits the line bandwidth of the outgoing highway to within the bandwidth of the line accommodated in the line adapter.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: April 3, 2001
    Assignee: Fujitsu Limited
    Inventors: Iwao Tada, Jyoei Kamoi, Tomoyuki Yamaguchi, Naoki Aihara