Patents by Inventor Trond Lokstad

Trond Lokstad 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: 8291105
    Abstract: The present invention relates to a method for identifying inaccurate time measurements in a local area network. The local area network comprises a sending device (2), such as a time client, a destination device (3), such as a timeserver, and a switching device and/or a store-and-forward device (6). A time request packet (4) is rejected if it arrives at the time client or timeserver within a given or calculated minimum distance from the preceding network packet. The time request packet (4) is also rejected if it falls outside a set of calculated error limits based on a set of estimates. Those estimates are kept in the time client memory and updated according to a given set of rules.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: October 16, 2012
    Assignee: ABB Research Ltd.
    Inventors: Øyvind Holmeide, Tor Skeie, Christoffer Apneseth, Svein Johannessen, Trond Lokstad
  • Publication number: 20040151125
    Abstract: The present invention relates to a method for identifying inaccurate time measurements in a local area network. The local area network comprises a sending device (2), such as a time client, a destination device (3), such as a timeserver, and a switching device and/or a store-and-forward device (6). A time request packet (4) is rejected if it arrives at the time client or timeserver within a given or calculated minimum distance from the preceding network packet. The time request packet (4) is also rejected if it falls outside a set of calculated error limits based on a set of estimates. Those estimates are kept in the time client memory and updated according to a given set of rules.
    Type: Application
    Filed: November 12, 2003
    Publication date: August 5, 2004
    Inventors: Oyvind Holmeide, Tor Skeie, Christoffer Apneseth, Svein Johanssen, Trond Lokstad
  • Publication number: 20040073718
    Abstract: A method for improved Network Time Protocol time synchronization in a computer network (1) where the computer network comprises a time client (2) and a timeserver (3). To eliminate network access errors at the client side, the actual time of leaving is stored in the time client (2) as a special time stamp (T11) and later substituted for T1 in the calculations. To eliminate network access errors at the server side, the time request packet is duplicated and returned twice, the second time containing the time stamp when the first packet left the server (T31). To eliminate network transversal jitter when using a switched network, a packet with a multicast is used and the time stamp (T11) is taken when the time request packet is reflected back from the switch and (T31) is taken when the reply packet is reflected back from the switch.
    Type: Application
    Filed: November 12, 2003
    Publication date: April 15, 2004
    Inventors: Svein Johannessen, Tor Skeie, Trond Lokstad