Reliable transmission method for transmitting traction information by block encryption

The invention discloses a reliable transmission method for transmitting traction information by block encryption, which comprises the following steps of: at a transmitter, signing a name on traction information m by using a public key cryptosystem, encrypting the traction information m by using a stream cipher S of which the secrete key is k0, splitting the traction information m into two subsequences m1 and m2, grouping according to a block cipher B, performing encryption by using a secrete key 1 and a secrete key 2, and encoding by using a cardinal number-91 conversion method to obtain encoded ciphertext C 1 and ciphertext C 2; encrypting a session key K={k0, k1, k2} by using the identity-based public key cryptosystem and by using a public key at a receiver to obtain the ciphertext C 3 of the session key; transmitting the ciphertext C 1, the ciphertext C 2 and the ciphertext C 3 of the encrypted session key by using three different common channels; and at a receiver, performing reverse operation at the transmitter on the received encoded ciphertext C 1, ciphertext C 2 and the ciphertext C 3 of the session key to obtain the traction information m which is transmitted by the transmitter. The information transmitted by the method has reliability and high security.