Abstract: This application discloses a network congestion control method and a network device, and relates to the field of communication technologies, to improve continuity and completion of a packet in a transmission process of a Transmission Control Protocol (TCP) flow. In this application, when pre-congestion (that is, congestion may occur) occurs in a forwarding direction of the TCP flow, a forwarding device reduces a value of a receive window (RWND) field in an acknowledge (ACK) packet, to reduce a sending rate of a transmit end for a packet in the TCP flow or delay sending of a packet by a transmit end. This relieves buffer pressure of the forwarding device, reduces a packet loss, and improves the continuity and the completion of the packet in the transmission process of the TCP flow.

Abstract: Embodiments of the application provide a data transmission method and a device. A sending device periodically obtains a first packet sequence number and a second packet sequence number. The first packet sequence number is a maximum value in packet sequence numbers respectively corresponding to packets that belong to a first data flow and that are received by a receiving device through a first data channel in a statistics period. The second packet sequence number is a maximum value in packet sequence numbers respectively corresponding to packets that belong to the first data flow and that are received by the receiving device through a second data channel in the statistics period. The sending device updates a packet cache queue of: the first data channel, the second data channel, or both the first and the second data channels, based on the first packet sequence number and the second packet sequence number.

Abstract: Embodiments of this application disclose a method, an apparatus, and a system for implementing data transmission. The method includes: obtaining, by a sending device, a data packet in a target data flow; and sending the data packet through each of at least two physical links between the sending device and a receiving device, where the data packet sent through each of the at least two physical links includes a same sequence number. Because the data packet in the target data flow is sent through different physical links, not through only one physical link, when a transmission latency of the data packet is increased due to a bandwidth instability factor such as burst traffic or electromagnetic wave interference on any physical link, the receiving device can combine, into a target video flow, data packets that are sent through other physical links and that have a lower latency.

Abstract: A data sending method, a sending device, a data receiving method, and a receiving device, the method including obtaining, by a sending device, a target medium access control protocol data unit (MPDU) by performing encapsulation processing on an internet protocol (IP) data packet of a specified service, where the sending device and a receiving device are connected through Wi-Fi, generating a backup MPDU of the target MPDU, and sending the target MPDU and the backup MPDU to the receiving device.

Abstract: Embodiments of this application disclose a method, an apparatus, and a system for implementing data transmission. The method includes: obtaining, by a sending device, a data packet in a target data flow; and sending the data packet through each of at least two physical links between the sending device and a receiving device, where the data packet sent through each of the at least two physical links includes a same sequence number. Because the data packet in the target data flow is sent through different physical links, not through only one physical link, when a transmission latency of the data packet is increased due to a bandwidth instability factor such as burst traffic or electromagnetic wave interference on any physical link, the receiving device can combine, into a target video flow, data packets that are sent through other physical links and that have a lower latency.

Abstract: A data transmission method includes: obtaining, by a sending device, data packets of a target data flow; and sending the data packets of the target data flow to a receiving device through at least two physical links between the sending device and the receiving device in a load balancing mode, where each data packet that is of the target data flow and that is sent in the load balancing mode carries a primary sequence number, the sent data packets of the target data flow have consecutive primary sequence numbers, and the primary sequence numbers are used by the receiving device to order data packets that are received from different physical links and that belong to the target data flow.

Abstract: Embodiments of the application provide a data transmission method and a device. A sending device periodically obtains a first packet sequence number and a second packet sequence number. The first packet sequence number is a maximum value in packet sequence numbers respectively corresponding to packets that belong to a first data flow and that are received by a receiving device through a first data channel in a statistics period. The second packet sequence number is a maximum value in packet sequence numbers respectively corresponding to packets that belong to the first data flow and that are received by the receiving device through a second data channel in the statistics period. The sending device updates a packet cache queue of: the first data channel, the second data channel, or both the first and the second data channels, based on the first packet sequence number and the second packet sequence number.

Abstract: A data sending method, a sending device, a data receiving method, and a receiving device, the method including obtaining, by a sending device, a target medium access control protocol data unit (MPDU) by performing encapsulation processing on an internet protocol (IP) data packet of a specified service, where the sending device and a receiving device are connected through Wi-Fi, generating a backup MPDU of the target MPDU, and sending the target MPDU and the backup MPDU to the receiving device.