Patents by Inventor Tsutomu Okurano

Tsutomu Okurano 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).

  • Data link layer processor system for a local exchange system
    Patent number: 6298040
    Abstract: A data link layer processing (DLLP) system comprises a plurality of in-service DLLPs and a plurality of spare DLLPs. The switching between the in-service DLLP and the spare DLLP is effected by coupling both the DLLPs with the transmission line and transferring logical links from the in-service DLLP to the spare DLLP one by one while frame multiplexing the data from the spare DLLP with the data from the in-service DLLP. After all of the logical links are transferred, a switch decouples the in-service DLLP to leave the spare DLLP coupled with the transmission line for a normal operation.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: October 2, 2001
    Assignee: NEC Corporation
    Inventors: Masato Aoyagi, Tomoyoshi Shimizu, Haruhiko Yamamura, Tsutomu Okurano