Data encoding method, data decoding method, and related device

A data encoding method, comprising:

• determining, by a transmitting end device, N data symbols at a same symbol location of N links of service data, wherein the N data symbols comprise one data symbol in each of the N links of service data, N is an integer greater than 1, each of the N data symbols comprises at least one bit, and quantities of bits comprised in all data symbols are the same;
• performing, by the transmitting end device, forward error correction (FEC) encoding on the N data symbols to obtain a codeword, wherein the codeword comprises the N data symbols and M overhead symbols, M is an integer greater than or equal to 1 and less than or equal to N, a quantity of bits in each data symbol is the same as a quantity of bits in each overhead symbol, and the M overhead symbols are configured to perform data recovery on a data symbol on which a transmission fault occurs in the N data symbols;
• and
• separately sending, by the transmitting end device, the N data symbols through N service channels, and separately sending the M overhead symbols through M overhead channels.