Data transmission method, device and equipment and readable storage medium

The invention discloses a data transmission method, device and equipment and a readable storage medium in the technical field of computers. According to the method, the second message is packaged by using the data transmission rule negotiated by the first forwarding end and the second forwarding end, the data transmission rule comprises the session mapping relation, when the method is applied to a VPN access scene, multiple sessions in a tunnel do not need to be transmitted to an external network through the same public network session, and the traffic blocking phenomenon in the remote access process is solved. Meanwhile, the transmission protocol and the data processing requirement in the data transmission rule can enable the second forwarding end and the first forwarding end to process the data transmitted between the second forwarding end and the first forwarding end according to the requirement negotiated by the two parties, thereby facilitating the expansion of the data transmission between the second fo