| Patent application number | Description | Published |
| 20090047018 | METHOD AND APPARATUS FOR L3-AWARE SWITCHING IN AN ETHERNET PASSIVE OPTICAL NETWORK - One embodiment of the present invention provides a system that performs layer 3 (L3) aware switching in an Ethernet passive optical network (EPON) which includes a central node and at least one remote node. During operation, the system maintains a set of mapping information which indicates a correspondence relationship between a logical link identifier of a remote node, a medium access control (MAC) address for a subscriber coupled to the remote node, and an IP address for the subscriber. Upon receiving a packet which contains an IP address, the system selectively attaches a proper logical link identifier to the packet based on the mapping information and the IP address contained in the packet, thereby allowing only one proper remote node to receive the packet. | 02-19-2009 |
| 20090262937 | METHOD AND APPARATUS FOR DATA PRIVACY IN PASSIVE OPTICAL NETWORKS - One embodiment provides a system for decrypting data frames in an Ethernet passive optical network (EPON). During operation, the system maintains a local cipher counter at a local node, and receives from a remote node a data frame which is encrypted based on a remote input block and a session key. The remote input block is constructed based on the remote cipher counter and a remote block counter. The system updates the local cipher counter based on a received field located in a preamble of the data frame, truncates the local cipher counter by discarding a number of least significant bits, and constructs for the received data frame a local input block based on the truncated local cipher counter, the received field, and a local block counter. The system then decrypts the data frame based on the local input block and the session key. | 10-22-2009 |
| 20100098407 | METHOD AND SYSTEM FOR PROTECTION SWITCHING IN ETHERNET PASSIVE OPTICAL NETWORKS - One embodiment provides a system that performs protection switching in an Ethernet passive optical network (EPON), which includes an optical line terminal (OLT) and at least one optical network unit (ONU). The system is configured with at least one redundant component for the OLT and/or ONUs, wherein the redundant component can be optical or electrical, and can be a port, line card or link. The system provides protection by detecting a failure, and switching automatically to the redundant components to reduce service disruption time. The protection switching comprises: preserving the existing configuration over the loss of at least one of a multiple-point control protocol (MPCP) message; an operations, administration and maintenance (OAM) message; and a signal on the physical layer. The system recovers from the failure without performing ONU discovery. | 04-22-2010 |
| 20100098412 | MANAGED PON REPEATER AND CROSS CONNECT - One embodiment provides an intelligent passive optical network (PON) node. The intelligent PON node includes a number of optical line terminal (OLT)-side transceivers coupled to a first optical fiber, a number of optical network unit (ONU)-side transceivers, a switching mechanism configured to couple the OLT-side transceivers and the ONU-side transceivers, and a controller configured to control the coupling operation of the switching mechanism. The OLT-side transceivers are configured to transmit optical signals on a number of wavelength channels to and receive optical signals on a number of wavelength channels from the OLT. A respective ONU-side transceiver is configured to transmit optical signals to and receive optical signals from a downstream PON. | 04-22-2010 |
| 20100098433 | SYNCHRONIZATION TRANSPORT OVER PASSIVE OPTICAL NETWORKS - One embodiment provides an Ethernet Passive Optical Network (EPON) system for clock transport. The system includes a reference clock configured to generate a frequency-reference signal, an optical line terminal (OLT) coupled to the reference clock, and an optical network unit (ONU). The OLT includes a clock generator configured to generate an OLT clock based on at least the frequency-reference signal. The ONU includes an optical transceiver, a clock recovery module, and a clock output mechanism. The optical transceiver is configured to transmit optical signals to and receive optical signals from the OLT. The clock-recovery module is configured to recover the frequency-reference signal from the received optical signals. The clock output mechanism is configured to output the recovered frequency-reference signal, thus facilitating transport of the frequency-reference signal over the EPON. | 04-22-2010 |
| 20100111523 | EPON WITH POWER-SAVING FEATURES - One embodiment provides a system for power saving in an Ethernet Passive Optic Network (EPON). The system includes an optical line terminal (OLT), an optical network unit (ONU), a traffic-detection module configured to detect status of traffic to and from the ONU, and a power-management module configured to place the ONU in sleep mode based on the detected traffic status. The ONU includes an optical transceiver that includes an optical transmitter configured to transmit optical signals to the OLT and an optical receiver configured to receive optical signals from the OLT. | 05-06-2010 |
| 20100239252 | METHODS AND APPARATUS FOR EXTENDING MAC CONTROL MESSAGES IN EPON - One embodiment provides a media access control (MAC) module facilitating operations of an Ethernet passive optical network (EPON). The MAC module includes a frame formatter configured to generate a MAC control frame. The generated MAC control frame includes at least one of: an organizationally unique identifier (OUI) field, an OUI-specific operation code (opcode) field, and a number of fields associated with the OUI-specific opcode. Transmission of the MAC control frame facilitates realization of an EPON function based on the fields associated with the OUI-specific opcode. | 09-23-2010 |
| 20100254706 | METHOD AND APPARATUS FOR LINK SHARING AMONG MULTIPLE EPONS - One embodiment of the present invention provides an optical line terminal (OLT) in an Ethernet passive optical network (EPON). The OLT includes a number of bi-direction optical transceivers. At least one bi-direction optical transceiver is coupled to an optical network unit (ONU) group that includes a number of ONUs. The OLT further includes a first downstream media access control (MAC) interface configured to provide a first downstream control signal and a splitter configured to split the first downstream control signal to a number of sub-signals. At least one sub-signal is configured to control downstream transmission of a corresponding bi-direction optical transceiver to a corresponding ONU-group. | 10-07-2010 |
| 20100329668 | Method and System for Optical Performance Monitoring in Ethernet Passive Optical Networks - One embodiment provides a system that tests optical performance in an Ethernet passive optical network (EPON), which includes an optical line terminal (OLT) and at least one optical network unit (ONU). The system configures an ONU with a circular queue that contains test frames for testing optical performance. The OLT then notifies the ONU to transmit test frames at a specified data rate for a specified duration. After receiving test frames at the OLT, the system measures frame loss and/or bit error rate based on the received test frames. | 12-30-2010 |
| 20110142447 | RF Signal Transport Over Passive Optical Networks - One embodiment provides an EPON for transporting RF signals. The system includes a reference clock, an ONU, and an OLT. The ONU includes a mechanism for receiving a frequency and phase-reference signal from the OLT, a mechanism for receiving an RF signal, an ADC for converting the RF signal into a digital signal using a sampling signal associated with the frequency and phase-reference signal, a mechanism for assembling at least a portion of the digital signal into a packet, a mechanism configured to timestamp the packet, and an optical transceiver. The OLT includes a mechanism for receiving the packet, a buffer, a delay mechanism configured to delay reading the received packet from the buffer for a predetermined amount of time, and a DAC for converting the digital signal included in the packet back to RF domain using a clock signal associated with the frequency and phase-reference signal. | 06-16-2011 |