Patents by Inventor Karl Scheffer

Karl Scheffer 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).

  • Method and system for transporting constant bit rate clients across a packet interface
    Patent number: 9019997
    Abstract: This disclosure describes a method and apparatus for signaling the phase and frequency of OTN and Constant Bit Rate (CBR) clients in an OTN network. The principles discussed are applicable when multiple stages of OTN multiplexing and demultiplexing are utilized. They are also applicable for use with the Generic Mapping Procedure (GMP) and Asynchronous Mapping Procedure (AMP). A method to use the phase and frequency of an ODUk/ODUflex to adjust a local reference clock to enable the recovery of the phase and frequency of a CBR client demapped from the ODUk/ODUflex is described.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: April 28, 2015
    Assignee: PMC-Sierra US, Inc.
    Inventors: Winston Ki-Cheong Mok, Karl Scheffer, Michael Smith
  • Control and coordination of ODUflex bandwidth resizing operation
    Patent number: 8854963
    Abstract: Methods and systems are provided for controlling elements in a signal path of a communication network to accommodate changes in the rate of a client signal. In particular, during the bandwidth resizing (BWR) portion of ITU-T Recommendation G.7044 Hitless Adjustment of ODUflex(GFP) protocol (HAO), the nodes in the chain along the ODUflex(GFP) signal path change their output rates in parallel such that FIFO over/underflow is avoided in the nodes. Certain embodiments provide mechanisms to synchronize and stabilize the nodes in a verifiable manner.
    Type: Grant
    Filed: May 8, 2012
    Date of Patent: October 7, 2014
    Assignee: PMC-Sierra US, Inc.
    Inventors: Scott Muma, Winston Ki-Cheong Mok, Steven Scott Gorshe, Karl Scheffer
  • Method and system for transporting constant bit rate clients across a packet interface
    Patent number: 8542708
    Abstract: A method and apparatus are described for signaling the phase and frequency of constant bit rate (CBR) clients over a network or fabric. An incoming CBR client stream is segmented into variable sized segments, such as packets or general framing protocol (GFP) frames, and is regenerated on the other side of a fabric or network phase-locked to the incoming stream. Regeneration of the CBR client clock is based solely on segment sizes, and in the case of GFP frames, the rate of the SONET Path or OTN ODUk stream carrying the GFP frames. No overhead bytes are inserted into the GFP frames to convey phase and frequency information. The method disclosed is important for reducing the cost and complexity of communications networks by allowing CBR clients to be transported with low jitter and wander without requiring the source and sink network elements to be phase-locked to a common stratum reference.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: September 24, 2013
    Assignee: PMC-Sierra US, Inc.
    Inventors: Winston Ki-Cheong Mok, Karl Scheffer