Patents by Inventor Yongdong Zhao

Yongdong Zhao 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).

  • Publication number: 20050147034
    Abstract: A weighted round-robin scheduler includes a round-robin table that stores a plurality of cycle link lists. Each cycle link list includes a head flow identification (FLID) value identifying a first flow of the cycle link list, and a tail FLID value identifying a last flow of the cycle link list. A flow table is provided having a plurality of flow table entries. Each flow table entry is associated with a corresponding flow. Each flow table entry stores a parameter that identifies the weight assigned to the associated flow. A packet queue is associated with each flow table entry, wherein each packet queue is capable of storing a plurality of packets. The weighted round-robin scheduler also includes an idle cycle register having an idle cycle entry corresponding with each of the cycle link lists, wherein each idle cycle entry identifies the corresponding cycle link list as active or idle.
    Type: Application
    Filed: August 25, 2004
    Publication date: July 7, 2005
    Inventors: Yongdong Zhao, Craig Lindahl
  • Publication number: 20050025052
    Abstract: An adjustable bit rate (ABR) feedback control scheme is provided where the effects of multiloop delays and high priority traffic transmission are built into the control model. The data traffic is filtered by a low pass filter. Then, the low frequency bandwidth of the filtered traffic is measured and compared to a predetermined threshold. If the measured value exceeds the threshold, the ABR traffic flow is reduced. If the measured value is less than the threshold, the ABR traffic flow is increased. In addition, a General Prediction Control (GPC) method may be applied to the control model for optimal performance. An object of the invention is to minimize the unused link capacity subject to no congestion, where the ABR traffic is adapted to the low frequency variation of high priority traffic flow for high efficiency.
    Type: Application
    Filed: August 20, 2004
    Publication date: February 3, 2005
    Applicants: SBC Technology Resources, Inc., University of Texas at Austin
    Inventors: Yongdong Zhao, San-Qi Li, Sam Sigarto
  • Publication number: 20030231590
    Abstract: A deficit round-robin scheduler including a round-robin table configured to store a plurality of cycle link lists, wherein each cycle link list includes a head flow identification (FLID) value identifying a first flow of the cycle link list, and a tail FLID value identifying a last flow of the cycle link list. A flow table is provided having a plurality of flow table entries, wherein each of the flow table entries is associated with a corresponding flow, and therefore has a corresponding FLID value. A packet queue is associated with each flow table entry, wherein each packet queue is capable of storing a plurality of packets. The deficit round-robin scheduler also included an idle cycle register having an idle cycle entry corresponding with each of the cycle link lists, wherein each idle cycle entry identifies the corresponding cycle link list as active or idle.
    Type: Application
    Filed: June 17, 2002
    Publication date: December 18, 2003
    Applicant: Integrated Device Technology, Inc.
    Inventors: Yongdong Zhao, Craig A. Lindahl
  • Publication number: 20030128703
    Abstract: A switch queue predictive protocol (SQPP) includes a packet switching system including: a switch fabric having a cross-point switch, and a plurality of line cards, each coupled to the switch fabric. A cross-point buffer is located at each cross-point of the cross-point switch. The switch fabric also includes a plurality of actual available queue space tables (AAQSTs), each identifying the actual queue space available in a row of the cross-point buffers. Each of the line cards includes an input buffer, an output buffer, and a predicted available queue space table (PAQST) identifying predicted queue space available in a corresponding row of the cross-point buffers. Packet information is transmitted from a source line card to the switch fabric only if available queue space is predicted by the corresponding PAQST. The switch fabric uses the AAQST to update the PAQST after packet information is transmitted to a destination line card.
    Type: Application
    Filed: January 3, 2002
    Publication date: July 10, 2003
    Inventors: Yongdong Zhao, Craig A. Lindahl
  • Publication number: 20030123455
    Abstract: A switch queue predictive protocol (SQPP) includes a packet switching system including: a switch fabric having a cross-point switch, and a plurality of line cards, each coupled to the switch fabric. A cross-point buffer is located at each cross-point of the cross-point switch. The switch fabric also includes a plurality of actual available queue space tables (AAQSTs), each identifying the actual queue space available in a row of the cross-point buffers. Each of the line cards includes an input buffer, an output buffer, and a predicted available queue space table (PAQST) identifying predicted queue space available in a corresponding row of the cross-point buffers. Packet information is transmitted from a source line card to the switch fabric only if available queue space is predicted by the corresponding PAQST. The switch fabric uses the AAQST to update the PAQST after packet information is transmitted to a destination line card.
    Type: Application
    Filed: January 3, 2002
    Publication date: July 3, 2003
    Inventors: Yongdong Zhao, Craig A. Lindahl
  • Publication number: 20030037159
    Abstract: A network device may perform traffic policing to determine if incoming data cells are in conformance with policing parameters, including a theoretical arrival time (TAT), for each cell's communication channel. Each cell may have an arrival time according to a timer value. The timer value and TAT may rollover upon reaching a maximum value. The network device may be configured to account for such rollovers when determining cell conformance. For each communication channel, a table entry may include the policing parameters and rollover data. Each entry may also include operations and maintenance (OAM) data. The rollover data indicates the rollover phase relationship between the timer value and TAT parameter for each channel. The rollover data may be updated each rollover phase of the timer, for example as part of an OAM table scan process. The network device may be an Asynchronous Transfer Mode (ATM) traffic policing device or switch.
    Type: Application
    Filed: August 6, 2001
    Publication date: February 20, 2003
    Inventors: Yongdong Zhao, Craig A. Lindahl
  • Patent number: 6144639
    Abstract: An adjustable bit rate (ABR) feedback control scheme is provided where the effects of multiloop delays and high priority traffic transmission are built into the control model. The data traffic is filtered by a low pass filter. Then, the low frequency bandwidth of the filtered traffic is measured and compared to a predetermined threshold. If the measured value exceeds the threshold, the ABR traffic flow is reduced. If the measured value is less than the threshold, the ABR traffic flow is increased. In addition, a General Prediction Control (GPC) method may be applied to the control model for optimal performance. An object of the invention is to minimize the unused link capacity subject to no congestion, where the ABR traffic is adapted to the low frequency variation of high priority traffic flow for high efficiency.
    Type: Grant
    Filed: September 3, 1997
    Date of Patent: November 7, 2000
    Assignees: SBC Technology Resources, Inc., The University of Texas at Austin, Texas
    Inventors: Yongdong Zhao, San-Qi Li, Sam Sigarto