Establishment method and device of cross-domain path

The present invention provides an establishment method and a device of a cross-domain path. The method comprises: a transport network controller set in a first network receiving a cross-domain path establishment request, wherein the cross-domain path establishment request comprises first and last node information and bandwidth information of a target path; based on topology information and TE information of the first network, obtaining a first sub-path of the target path in the first network; based on the bandwidth information, allocating network resources for links between nodes on the first sub-path for each node to establish a connection; sending a path message to a second boundary node of a second network for the second boundary node to run a signaling protocol in a GMPLS protocol stack based on the path message so as to establish a second sub-path of the target path in the second network, and completing connections between nodes on the second sub-path; after receiving a network resource corresponding to a cross-domain link sent by the second boundary node, sending an instruction message to a first boundary node for the first boundary node to connect the first sub-path and the second sub-path.