1. A Path Computation Element (PCE) comprising: a receiver configured to receive a path computation request from a path computation client (PCC), the path computation request requesting computation for a path from a head end node to a tail end node; a processor coupled to the receiver and configured to: compute a path from the head end node to the tail end node in response to the path computation request; and assign a first Multiprotocol Label Switching (MPLS) label for a Software Defined Network (SDN) compatible node in the computed path, wherein the first MPLS label associated with to a label switched path (LSP) which traverses each node in the computed path; and a transmitter coupled to the processor and configured to transmit the first MPLS label directly to the SDN compatible node via PCE protocol (PCEP).