DCN soft switching device and method based on SDH equipment

The invention relates to the technical field of optical communication, in particular to a DCN (Data Communication Network) soft switching device and method based on SDH (Synchronous Digital Hierarchy) equipment, a processing module executes VLAN (Virtual Local Area Network) ID (Identity) packaging according to a slot number and an address of a target service board, and forwards a data packet to a first communication module; the first communication module analyzes the data packet and reconstructs the data packet, and forwards the data packet to a specified port according to port information corresponding to the VLAN ID; and the second communication module removes the VLAN ID in the data packet, reconstructs the data packet and forwards the data packet to the control module. The Ethernet protocol and the SDH are converted, so that the dependence on an exchange chip and the usable area of the board cards are reduced, meanwhile, high-speed and reliable data transmission between the SDH equipment board cards is re