Data transmission method, communication apparatus, and communication system

A data transmission method, wherein the method comprises:

• obtaining N ciphertext data streams, wherein a first ciphertext data stream is any ciphertext data stream in the N ciphertext data streams, the first ciphertext data stream comprises at least two first alignment markers AMs and at least two ciphertext data segments, one ciphertext data segment is comprised between every two first AMs, one first AM is comprised between every two ciphertext data segments, the at least two first AMs are used for aligning data of the N ciphertext data streams, some or all of the first AMs in the at least two first AMs indicate encryption parameters of the at least two ciphertext data segments, and Nis a positive integer;
• and
• decrypting the first ciphertext data stream based on the encryption parameters of the at least two ciphertext data segments, to obtain a first plaintext data stream, wherein the first plaintext data stream is any plaintext data stream in N plaintext data streams.