Method and system for establishing safety connection between nodes

The present invention discloses a method and a system for establishing safety connection between nodes. The method comprises that: a transmitting source node N Source transmits a key request packet to a first switching equipment SW First ; the first switching equipment SW First transmits a temporary key announcement packet to a second switching equipment SW Last ; the second switching equipment SW Last transmits a key announcement packet to a destination node N Destination ; the destination node N Destination transmits a key announcement response packet to the second switching equipment SW Last ; the second switching equipment SW Last transmits a temporary key announcement response packet to the first switching equipment SW First ; the first switching equipment SW First transmits a key response packet to the transmitting source node N Source ; the transmitting source node N Source receives the key response packet. By using the method, shared static keys are not needed to be deployed between every two nodes.