SPRING: LDP and IGP shortcuts over non-colored SR-TE tunnel

This feature introduces IGP shortcuts with LDP tunnels over non-colored SR-TE tunnels. You can configure more than one tunnel source protocol for IGPs to create shortcut routes. When more than one tunnel source protocol is configured and if the tunnels from more than one protocol are available to a destination, the tunnel with the most preferred route is established. For example, if the core network has both RSVP LSPs and SR-TE LSPs and LDP tunneling is enabled for both RSVP and SR-TE LSPs, then the tunnel-source-protocol configuration selects the tunnel based on the preference value.