This application provides a data transmission method and apparatus. The method includes: processing, by a network device, a to-be-sent optical data unit ODU to obtain another ODU, where a bit rate of the another ODU is lower than a bit rate of the ODU; and sending, by the network device, the another ODU. In embodiments of this application, the ODU is processed to obtain the another ODU with a lower bit rate, and this helps reduce a rate increase when service data is transmitted in an OTN, so as to reduce an OTN interface rate and OTN costs.

A transmission rate adjustment method and a network device, the method including obtaining, by a network device, a target data stream, where the target data stream includes a first data packet, and where the first data packet includes at least two non-idle units, and inserting or deleting a padding unit between two non-idle units of the at least two non-idle units, in response to bandwidth adjustment needing to be performed, and according to a value of the bandwidth adjustment that needs to be performed, where the padding unit provides adaption to a difference between a bandwidth of an upstream transmission channel of the network device and a bandwidth of a downstream transmission channel of the network device.

A transmission rate adjustment method and a network device, the method including obtaining, by a network device, a target data stream, where the target data stream includes a first data packet, and where the first data packet includes at least two non-idle units, and inserting or deleting a padding unit between two non-idle units of the at least two non-idle units, in response to bandwidth adjustment needing to be performed, and according to a value of the bandwidth adjustment that needs to be performed, where the padding unit provides adaption to a difference between a bandwidth of an upstream transmission channel of the network device and a bandwidth of a downstream transmission channel of the network device.

A source node for rate adapting a constant bit rate client signal into a signal stream in a 64B/66B-block telecom signal communication link includes a GMP engine; a FIFO buffer coupled to receive a 64B/66B encoded client data stream; a clock rate measuring circuit; a source of 64B/66B path overhead blocks; a source of 64B/66B pad blocks; a source of 64B/66B idle blocks; a multiplexer; and a multiplexer controller. A control 64B/66B block is encoded into an ordered set block-designator and a count of data blocks to be sent in a next path signal frame is encoded into a plurality of path overhead 64B/66B data blocks. The multiplexer controller is responsive to a count of data blocks to be sent in a next path signal frame from a previous GMP window frame to selectively pass data to a data output so as to fill a GMP window frame.

This application provides a data transmission method and apparatus. The method includes: processing, by a network device, a to-be-sent optical data unit ODU to obtain another ODU, where a bit rate of the another ODU is lower than a bit rate of the ODU; and sending, by the network device, the another ODU. In embodiments of this application, the ODU is processed to obtain the another ODU with a lower bit rate, and this helps reduce a rate increase when service data is transmitted in an OTN, so as to reduce an OTN interface rate and OTN costs.

A first network element includes trail trace identifier information in an optical network frame. The first network element obtains data to transmit over an optical network link to a second network element. The first network element generates an optical network frame with alignment marker bytes, which are followed by padding bytes. The optical network frame also includes overhead bytes following the padding bytes. The overhead bytes include a Multi-Frame Alignment Signal (MFAS) byte, a link status byte, and reserved bytes. The optical network frame also includes a payload bytes following the overhead bytes. The payload bytes encode at least a portion of the data to transmit to the second network element. The first network element inserts trail trace identifier information into the reserved bytes in the overhead bytes. The trail trace identifier information identifies the first network element as a source of the optical network frame.

This application provides data transmission methods and apparatuses. One method includes: processing, by a network device, a first optical data unit (ODU) to obtain a second ODU, wherein a bit rate of the second ODU is lower than a bit rate of the first ODU; and sending, by the network device, the second ODU.

A communication method, device, and a storage medium to resolve a problem that information about a clock frequency and a clock phase of a service cannot be correctly transmitted to a receiver or correctly recovered because transparent transmission of the information about the clock frequency and the clock phase of the service cannot be implemented. Because a value of k based on a reference data unit is inserted into a second data flow, and the value of k can indicate a quantity of third data units included between a second data unit and the reference data unit in a first data flow, a receive end device can completely recover the first data flow based on the value of k.

A system, method, and apparatus enabling synchronous and asynchronous data sources to be demapped from an oFrame container using a generic mapping system.

A byte stuffing circuit and a byte stuffing method are provided. The byte stuffing method includes: receiving a first data stream and generating a second data stream according to the first data stream, where a first size of the first data stream is N bytes, and a second size of the second data stream is 2N bytes; in response to an Xth byte of the second data stream matching a first flag byte, overwriting the Xth byte with a first stuffing byte, and inserting a second stuffing byte into an (X+1)th byte of the second data stream, where X is a positive integer between 1 and 2N−1; combining a remnant data stream and a first part of the second data stream to generate a third data stream, and configuring a second part of the second data stream as the remnant data stream; and outputting the third data stream.