Abstract: The present disclosure relates to passive optical network (PON) systems, an optical line terminal (OLT), and an optical network unit (ONU). One example PON system includes an OLT and at least two ONUs, and the OLT and the ONUs exchange data on one downstream channel and two upstream channels. The OLT sends downstream data to each ONU on the downstream channel, where the downstream data includes an upstream bandwidth grant which is used to control the ONU to send upstream data. Each ONU receives the downstream data on the downstream channel, and sends the upstream data on a first upstream channel or a second upstream channel based on the upstream bandwidth grant included in the downstream data. The OLT receives, on the first upstream channel and the second upstream channel, the upstream data sent by each ONU.

Abstract: The present disclosure relates to passive optical network (PON) systems, an optical line terminal (OLT), and an optical network unit (ONU). One example PON system includes an OLT and at least two ONUs, and the OLT and the ONUs exchange data on one downstream channel and two upstream channels. The OLT sends downstream data to each ONU on the downstream channel, where the downstream data includes an upstream bandwidth grant which is used to control the ONU to send upstream data. Each ONU receives the downstream data on the downstream channel, and sends the upstream data on a first upstream channel or a second upstream channel based on the upstream bandwidth grant included in the downstream data. The OLT receives, on the first upstream channel and the second upstream channel, the upstream data sent by each ONU.

Abstract: The present disclosure relates to passive optical network (PON) systems, optical line terminals (OTLs), and optical network units (ONUs). One example PON system includes an OLT and at least two ONUs. The OLT and the ONUs exchange data on one downstream channel and two upstream channels. The OLT sends downstream data to each ONU on the downstream channel, where the downstream data includes an upstream bandwidth grant used to control each ONU to send upstream data. Each ONU receives the downstream data on the downstream channel, and sends the upstream data on a first upstream channel or a second upstream channel based on the upstream bandwidth grant included in the downstream data. The OLT receives, on the first upstream channel and the second upstream channel, the upstream data sent by each ONU, where a registration function is disabled on the first upstream channel, and enabled on the second upstream channel.

Abstract: This application discloses a communication method, an optical line terminal, and an optical network unit in a passive optical network system. The PON system includes an OLT and at least one ONU, and the method includes: receiving, by the OLT, a first message that is sent by a first ONU in the at least one ONU through a first upstream channel; determining a first round trip time (RTT) of the first ONU based on a receiving moment of the first message; determining a time window based on the first RTT; sending first indication information to the first ONU through a downstream channel, where the first indication information includes the time window; receiving a second message that is sent by the first ONU through a second upstream channel within the time window; and determining a second RTT of the first ONU based on a receiving moment of the second message.

Abstract: A framing method and apparatus in a passive optical network (PON) and a system, where the method includes generating a first transmission convergence (TC) frame and a second TC frame separately, wherein a sum of frame lengths of the first and the second TC frame is 125 microseconds (?s), performing bit mapping on the second TC frame to generate a third TC frame, where the bit mapping refers to identifying each bit of the second TC frame using N bits, and sending the first and the second TC frame to an optical network unit (ONU). A line rate corresponding to the second TC frame is lower than 2.488 giga bits per second (Gbps) such that a rate of a receiver on a receiving side is decreased and a bandwidth of the receiver is narrowed, thereby decreasing an optical link loss and increasing an optical power budget.

Abstract: This application discloses a communication method, an optical line terminal, and an optical network unit in a passive optical network system. The PON system includes an OLT and at least one ONU, and the method includes: receiving, by the OLT, a first message that is sent by a first ONU in the at least one ONU through a first upstream channel; determining a first round trip time (RTT) of the first ONU based on a receiving moment of the first message; determining a time window based on the first RTT; sending first indication information to the first ONU through a downstream channel, where the first indication information includes the time window; receiving a second message that is sent by the first ONU through a second upstream channel within the time window; and determining a second RTT of the first ONU based on a receiving moment of the second message.

Abstract: The present disclosure relates to passive optical network (PON) systems, optical line terminals (OTLs), and optical network units (ONUs). One example PON system includes an OLT and at least two ONUs. The OLT and the ONUs exchange data on one downstream channel and two upstream channels. The OLT sends downstream data to each ONU on the downstream channel, where the downstream data includes an upstream bandwidth grant used to control each ONU to send upstream data. Each ONU receives the downstream data on the downstream channel, and sends the upstream data on a first upstream channel or a second upstream channel based on the upstream bandwidth grant included in the downstream data. The OLT receives, on the first upstream channel and the second upstream channel, the upstream data sent by each ONU, where a registration function is disabled on the first upstream channel, and enabled on the second upstream channel.

Abstract: A computer-implemented method of handling Ethernet packets in a passive optical network (PON) is disclosed. The method comprises generating, by the one or more processors, an initial envelope header that indicates that the initial envelope header is not a preamble replacement; transmitting, over the PON, by the one or more processors, the initial envelope header; accessing, by the one or more processors, an eight-byte block from a first Ethernet packet of a plurality of Ethernet packets; in response to the eight-byte block being an Ethernet preamble, generating, by the one or more processors, a first envelope header that indicates that the envelope header is a preamble replacement; and transmitting, over the PON, by the one or more processors, the first envelope header.

Abstract: A computer-implemented method of handling Ethernet packets in a passive optical network (PON) is disclosed. The method comprises generating, by the one or more processors, an initial envelope header that indicates that the initial envelope header is not a preamble replacement; transmitting, over the PON, by the one or more processors, the initial envelope header; accessing, by the one or more processors, an eight-byte block from a first Ethernet packet of a plurality of Ethernet packets; in response to the eight-byte block being an Ethernet preamble, generating, by the one or more processors, a first envelope header that indicates that the envelope header is a preamble replacement; and transmitting, over the PON, by the one or more processors, the first envelope header.

Abstract: A framing method and apparatus in a passive optical network (PON) and a system, where the method includes generating a first transmission convergence (TC) frame and a second TC frame separately, wherein a sum of frame lengths of the first and the second TC frame is 125 microseconds (?s), performing bit mapping on the second TC frame to generate a third TC frame, where the bit mapping refers to identifying each bit of the second TC frame using N bits, and sending the first and the second TC frame to an optical network unit (ONU). A line rate corresponding to the second TC frame is lower than 2.488 giga bits per second (Gbps) such that a rate of a receiver on a receiving side is decreased and a bandwidth of the receiver is narrowed, thereby decreasing an optical link loss and increasing an optical power budget.

Abstract: The present invention discloses a message transmission method, an apparatus, and a system. The method includes: obtaining physical layer operation, administration and maintenance information between an optical line terminal and an optical network unit; fragmenting the physical layer operation, administration and maintenance information, to obtain multiple fragments; generating a first message, where the first message includes: a first message type identifier field, used to identify a type of the first message; a message length field, used to identify a length of a fragment carried in the first message; an action indication field, used to identify whether the fragment carried in the first message is the last fragment; a first fragment sequence number field, used to identify a sequence number of the fragment carried in the first message; and a message content field, used to carry a fragment in the multiple fragments; and sending the first message.

Abstract: An error correction method is disclosed, including receiving an input data, processing the input data with a first Forward Error Code (FEC) transformation, processing the input data with a second FEC transformation, and generating an output data including the first transformation and the second transformation.