Patent attributes
A Software Defined Network (SDN) controller determines a plurality of paths for transmitting a data stream from a first network device to a second network device. The SDN controller assigns to each of the plurality of paths a path identifier, where the path identifier is uniquely corresponding to the path and the specified service. The SDN controller delivers forwarding information to a network device other than the second network device on the path. The forwarding information is configured to instruct forwarding a data stream carrying the path identifier of the path to a next hop on the path of a network device receiving the forwarding information. The SDN controller selects a path from the plurality of paths and transmits a path identifier of the selected path to the first network device. The first network device adds the path identifier of the selected path to the data stream of the specified service.