Support for FEC 128 and FEC 129 VPLS with source packet routing (MX Series)—Starting in Junos OS Release 20.3R1, Junos OS supports forwarding equivalence class (FEC) 128 and FEC 129 VPLS with Source Packet Routing in Networking (SPRING) with IS-IS, OSPF, and non-colored segment routing–traffic-engineering (SR-TE). Source packet routing or segment routing is applied in an MPLS network. You can use FEC 128 and FEC 129 VPLS with SPRING over MPLS as an alternative to LDP VPLS over MPLS.