摘要:
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.
摘要:
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.
摘要:
One embodiment of the present invention provides a system that accommodates different clock frequencies in an Ethernet passive optical network (EPON). The system receives a signal from an optical line terminal (OLT) at an optical network unit (ONU) and derives an OLT clock. The system also maintains a local clock. The system further receives from the OLT an assignment for an upstream transmission window, during which the ONU can transmit an upstream data burst to the OLT based on the local clock. The system adjusts the number of bits of the data burst without affecting the payload data carried in the data burst, thereby allowing the data burst to fit properly within the upstream transmission window and compensating for frequency differences between the local clock and the OLT clock. The system transmits the data burst based on the local clock in the upstream transmission window.
摘要:
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.
摘要:
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.
摘要:
One embodiment of the present invention provides a system that accommodates different clock frequencies in an Ethernet passive optical network (EPON). The system receives a signal from an optical line terminal (OLT) at an optical network unit (ONU) and derives an OLT clock. The system also maintains a local clock. The system further receives from the OLT an assignment for an upstream transmission window, during which the ONU can transmit an upstream data burst to the OLT based on the local clock. The system adjusts the number of bits of the data burst without affecting the payload data carried in the data burst, thereby allowing the data burst to fit properly within the upstream transmission window and compensating for frequency differences between the local clock and the OLT clock. The system transmits the data burst based on the local clock in the upstream transmission window.
摘要:
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.
摘要:
One embodiment of the present invention provides a system for accommodating time-division multiplexing (TDM) traffic in an Ethernet passive optical network (EPON). During operation, the system receives data from an upstream TDM channel at a remote node and stores received data in a segmentation buffer. The system encapsulates the data stored in the segmentation buffer into a packet. The system receives a message from the central node granting a TDM transmission window starting at a designated time. The system further communicates the packet to an upstream transmission mechanism within the remote node before the designated time, and transmits to the central node an upstream frame containing the packet at the designated time.
摘要:
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.
摘要:
One embodiment of the present invention provides a system that accommodates different clock frequencies in an EPON. The system receives a signal from the OLT at the ONU and derives an OLT clock. The system also maintains a local clock. The system further receives from the OLT an assignment for an upstream transmission window, during which the ONU can transmit an upstream data burst to the OLT based on the local clock. The system adjusts the number of bits of the data burst without affecting the payload data carried in the data burst, thereby allowing the data burst to fit properly within the upstream transmission window and compensating for frequency differences between the local clock and the OLT clock. The system transmits the data burst based on the local clock in the upstream transmission window.