Patents by Inventor Tae-Whan Yoo

Tae-Whan Yoo 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: 20090135826
    Abstract: The present invention relates to an apparatus and method of classifying packets that can support a quality of service (QoS) in a network system.
    Type: Application
    Filed: September 8, 2008
    Publication date: May 28, 2009
    Applicant: ELECTRONIC AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Jung Hak KIM, Tae Whan Yoo, Song In Choi
  • Patent number: 7539424
    Abstract: Provided is a burst mode optical receiver capable of accurately detecting an optical signal of minimum amplitude, by automatically controlling a gain of a pre-amplifier according to an amplitude of an input optical signal. The burst mode optical receiver can automatically control a gain of a pre-amplifier according to the amplitude of an input optical signal using an output signal of a first peak detector. In other words, when the input optical signal has a small amplitude that meets the receiving sensitivity of the burst mode optical receiver, the gain of the pre-amplifier automatically increases, thereby improving the receiving sensitivity of the burst mode optical receiver.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: May 26, 2009
    Assignees: Electronics and Telecommunications Research Institute, Information and Communications University
    Inventors: Ho Yong Kang, Hyun Kyun Choi, Tae Whan Yoo, Hyeong Ho Lee, Sang Gug Lee, Man Seop Lee, Ja Won Seo
  • Patent number: 7502328
    Abstract: Provided is a method of monitoring link performance and diagnosing an active link state without interrupting traffic in an Ethernet passive optical network (EPON) while the link is in the active state.
    Type: Grant
    Filed: November 22, 2005
    Date of Patent: March 10, 2009
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ho Sook Lee, Jee Sook Eun, Tae Whan Yoo, Bong Tae Kim
  • Patent number: 7443861
    Abstract: A method of controlling data transmission in an Ethernet passive optical network (EPON) and an apparatus thereof are provided. Transmission permission messages using a mode of bandwidth allocation are queued in a queuing unit according to the types of the transmission permission messages. A transmission time duration of upstream data is defined for each of the transmission permission messages queued in the queuing unit. A bandwidth allocation unit generates transmission permission messages to allocate upstream data transmission bandwidth for an optical network unit (ONU), based on the transmission permission messages stored in the storage unit. A scheduler designates the predetermined priority, reads transmission permission messages from queues according to a predetermined priority, determines a transmission start time of upstream data, and outputs the transmission permission messages.
    Type: Grant
    Filed: November 3, 2003
    Date of Patent: October 28, 2008
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ho Sook Lee, Tae Whan Yoo, Hyeong Ho Lee
  • Publication number: 20080198857
    Abstract: The invention relates to an EPON bridge apparatus and a forwarding method thereof. In case of receiving frame from the network port or the PON port, the apparatus associates the port having the received frame inputted with source MAC address of the received frame to learn the information in an FDB table which manages port information for the learned MAC address. Then the apparatus refers to the FDB table to remove LLID from upstream frame, and then forwards the upstream frame to the network port, while attaching LLID corresponding to destination MAC address to downstream frame to transmit to the PON port. Bridging between ONUs are possible with flooding capability using anti-LLID. It provides VLAN-LLID translation mode with support for VLAN tag addition/removal at the ONU side. It also provides multicast pruning function for the downstream.
    Type: Application
    Filed: September 1, 2006
    Publication date: August 21, 2008
    Inventors: Chan Kim, Tae Whan Yoo, Yool Kwon, Bong-Tae Kim
  • Publication number: 20080130657
    Abstract: Provided are method and apparatus for dynamically allocating unlink bandwidth in Ethernet PON. In the method and apparatus, report value, which are received for each logical link identifications (LLID), is controlled to be less than a maximum gate value set for each LLID in sequence for all of LLIDs without a predetermined interval. A gate having a length corresponding to the restricted report value is generated. LLIDs are grouped into classes and processing is done class by class. For each class processing, if maximum processing time is reached or maximum total allocation is reached, the processing is switched to a lower class. Also each class processing, if any higher class has its maximum yield processing time or maximum yield allocated gate reached, the processing is switched to that higher class.
    Type: Application
    Filed: November 30, 2007
    Publication date: June 5, 2008
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Chan KIM, Tae Whan YOO, Bong Tae KIM
  • Patent number: 7379676
    Abstract: Provided is a communication apparatus in a PON bridge sublayer, which supports point-to-point communications between optical network units (ONU) in an Ethernet passive optical network (EPON). To support point-to-point communications between ONUs in the EPON, the communication apparatus in the PON bridge sublayer includes a second processing portion, a second input queue, a second lookup and learning portion, a second output queue, a first input queue, a first lookup and learning portion, a filtering database table a VLAN ID table, a table control portion, a first output queue, and a first processing portion.
    Type: Grant
    Filed: November 25, 2003
    Date of Patent: May 27, 2008
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ho Yong Kang, Tae Whan Yoo, Hyeong Ho Lee
  • Patent number: 7372854
    Abstract: A communication node system for an Ethernet-PON includes: an LLID register for storing an LLID being an allocated identifier; a preamble generator for generating a PON preamble; a CRC generator for generating a CRC for the preamble; a transmission connector for combining transport data with the CRC-including preamble to generate a transport frame, and forwarding the transport frame; a reception connector for receiving the frame and dividing the frame into a preamble and received data; a filter for extracting an LLID from the preamble, comparing the extracted LLID with the LLID stored in the register, and selectively filtering the extracted LLID; and a received frame generator for discarding the received data, or combining the received data with the preamble to generate a received frame.
    Type: Grant
    Filed: August 1, 2003
    Date of Patent: May 13, 2008
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ho-Yong Kang, Tae-Whan Yoo, Hyeong-Ho Lee
  • Patent number: 7369781
    Abstract: Provided is a burst mode optical receiver considering a characteristic of an extinction ratio of a received optical signal is provided. By using a peak detector considering a characteristic of an extinction ratio, top and bottom peak voltages of actual burst packets can be precisely detected while not being affected by a DC offset corresponding to an extinction ratio even though burst packets having a DC offset corresponding to the extinction ratio are received. Accordingly, waveform distortion of a signal output from the burst mode optical receiver can be minimized.
    Type: Grant
    Filed: November 10, 2003
    Date of Patent: May 6, 2008
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ja Won Seo, Ho Yong Kang, Hyun Kyun Choi, Tae Whan Yoo, Hyeong Ho Lee, Sang Gug Lee, Man Seop Lee
  • Patent number: 7313751
    Abstract: A dual mode decoder which includes an MB810 decoder; an 8B/10B decoder; a mode detection unit, a first low pass filter; a second low pass filter; an IDLE code detection unit which detects IDLE code and transfers to the mode detection unit; a first switch unit which selectively outputs the 10-bit code input from the first low pass filter and the second low pass filter; a parallel conversion unit which outputs a 10-bit parallel code; a first selection unit which provides the 10-bit parallel code to the decoder determined as the operation decoder between the MB810 decoder and the 8B/10B decoder; and a second selection unit which selectively outputs an 8-bit code corresponding to the 10-bit parallel code input form the decoder determined as the operation decoder.
    Type: Grant
    Filed: September 20, 2005
    Date of Patent: December 25, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sungsoo Kang, Tae Whan Yoo, Hyeong Ho Lee
  • Patent number: 7301970
    Abstract: A MAC master apparatus for executing a multi-point control protocol (MPCP) data in an optical line termination (OLT) of an Ethernet passive optical network (PON) is provided. The MPCP master apparatus includes a CPU interface unit, two or more memory arbitration control units, a SGA table memory, a RTT table memory, a static grant generation unit, a dynamic grant generation unit, a static grant queue, a dynamic grant queue, a sending message queue, a sending multiplexing unit, a time setting unit, a receiving window generation unit, an upstream grant queue, a received demultiplexing unit, a report queue and a received message queue. Therefore, any frame, including MPCP frames from/to the CPU can be sent or received, and a grant can be allocated statically according to a setting or dynamically according to a report from the ONUs.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: November 27, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chan Kim, Ho Sook Lee, Tae Whan Yoo, Hyeong Ho Lee
  • Patent number: 7290202
    Abstract: An MB810 encoder and/or decoder, dual mode encoder and/or decoder, and a method for generating MB810 codes are provided. Twelve state points in the form of a 4×3 matrix on a state transition map are formed with binary unit digital sum variation & alternate sum variation (BUDA). A 10-bit code from 8-bit data is generated outputting a 10-bit code from a predetermined state point to form the matrix. Codes forming a complementary pair from a set of codes capable of arriving at state points forming the matrix are selected. Codes forming the 12 state points by supplementing state points lacked in the codes forming a complementary pair are selected. Control codes including IDLE code from the codes forming the 12 state points are selected. Codes generating the IDLE code by a bit string between neighboring codes among the codes forming the 12 state points are removed.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: October 30, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sungsoo Kang, Tae Whan Yoo, Hyeong Ho Lee
  • Patent number: 7274695
    Abstract: A method and apparatus for processing Ethernet data frames in a media access control (MAC) sublayer of an Ethernet passive optical network (PON) are provided.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: September 25, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seung Hwan Kim, Tae Whan Yoo, Hyeong Ho Lee
  • Patent number: 7245641
    Abstract: Disclosed herein is a variable length packet switching system. The variable length packet switching system includes at least two switching means, a plurality of multiplexing units and a plurality of demultiplexing units. The switching means switch ATM cells or variable length packet data in parallel. The multiplexing means are arranged upstream of the switching means for multiplexing data inputted from a line card to the switching means in packet units and dividing a packet into packets of a number corresponding to the number of the switching means. The demultiplexing means are arranged downstream of the switching means for combining packets inputted after being switched in parallel by the at least two switching means and outputting the combined packet converted into a format adequate to the line card.
    Type: Grant
    Filed: September 19, 2002
    Date of Patent: July 17, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chan Kim, Kyeong Soo Han, Je Soo Ko, Tae Whan Yoo, Jong Hyun Lee
  • Publication number: 20070127487
    Abstract: A method for managing a service bandwidth by a customer port and an EPON system using the same are provided. In order to manage the service bandwidth by a customer, ONU and ONT allocate a service class according to a combination of information about a customer that receives a service, and a service type and a service priority of a service provided to a customer, allocate a bandwidth according to each service class and control a uplink bandwidth or a downlink bandwidth according to a service class. Also, a system manger collects information about a service provider, a service provided from a service provider, a customer that receives a service, and information for classifying a service. After collecting, the system manager provides the collected information to the ONU and the OLT.
    Type: Application
    Filed: December 7, 2006
    Publication date: June 7, 2007
    Inventors: Jung Hak Kim, Tae Whan Yoo, Hoon Lee, Yool Kwon, Bong Tae Kim
  • Patent number: 7224694
    Abstract: An apparatus for and a method of generating pointers for identifying structure boundaries of data for leased lines such as T1/E1 in an asynchronous transfer mode (ATM) adaptation layer Type 1 (AAL1) through an ATM layer.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: May 29, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ho Yong Kang, Je Soo Ko, Tae Whan Yoo
  • Patent number: 7205911
    Abstract: An apparatus and method for checking validity of an 8B/10B code-group are provided. The apparatus for checking validity of an 8B/10B code-group includes a 6B/5B disparity classification unit, a 4B/3B disparity classification unit, an RD6 detection unit, an RD4 detection unit, an 8B/10B code-group rule violation detection unit, an RD error detection unit, and a unit for outputting 8B/10B code-group validity. The apparatus receives an 8B/10B code-group, divides into a least significant 6-bit nibble and a most significant 4-bit nibble, detects a running disparity, and by doing so, determines the validity of a code-group. The apparatus and method for checking validity of an 8B/10B code-group relatively shortens the critical path, which indicates the number of combinational logic circuits that should be operated in a unit time, and therefore the apparatus and method are appropriate to high-speed systems such as gigabit Ethernet systems.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: April 17, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Junghak Kim, Tae Whan Yoo, Hyeong Ho Lee
  • Patent number: 7194672
    Abstract: An apparatus and method for detecting errors in received data and transferring only error-free data in data communications are provided. In the cyclic redundancy check (CRC) verification apparatus and method having a constant delay, irrespective of the length of a received data frame, input and output processing delay of received data is made to be constant. The CRC verification apparatus having constant delay comprises an input control unit which stores the start address of an input data frame in a memory storing the input data frame, and stores a CRC verification result in the start address location; and an output control unit which after a predetermined constant time passes from the start address, reads an input data frame and if the CRC verification result is normal, output the read data frame. The apparatus and method make the time taken for receiving a data frame, constant irrespective of the received data frame, while CRC verification is performed.
    Type: Grant
    Filed: November 25, 2003
    Date of Patent: March 20, 2007
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chan Kim, Seung Hwan Kim, Tae Whan Yoo, Hyeong Ho Lee
  • Patent number: 7142544
    Abstract: A PON slave controller for use in a PON ONU system capable of processing in unit of byte outputs an enable signal to external for a mini-slot payload and receives a byte input signal for enabling usage of an arbitrary MAC (Medium Access Control) technique loading arbitrary data in a mini-slot.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: November 28, 2006
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chan Kim, Seung-Hwan Kim, Tae-Whan Yoo, Jong-Hyun Lee
  • Publication number: 20060221841
    Abstract: Provided is a method of monitoring link performance and diagnosing an active link state without interrupting traffic in an Ethernet passive optical network (EPON) while the link is in the active state.
    Type: Application
    Filed: November 22, 2005
    Publication date: October 5, 2006
    Inventors: Ho Lee, Jee Eun, Tae Whan Yoo, Bong Kim