LSP creation

To create TE tunnels, P2MP LSPs, TE LSPs, and subLSPs, the MPLS Topology Server consults the LSP table manager and examines the LSP-tunnel header information to create instances of the LSPs.

To create LDP LSPs, the MPLS Topology Server consults the LSP table manager and stitches LSP hops together to create instances of the LSPs.

An LSP ID for a TE LSP or subLSP is a 2-byte identifier that is used by the LSP-tunnel headend to set up the LSP. The MPLS Topology Server discovers the LSP ID during per-device discovery. During postprocessing discovery, the MPLS Topology Server converts the LSP ID to a 4-byte identifier that identifies the destination IP address of the LSP.

An LSP ID for an LDP LSP is a 4-byte identifier that identifies the destination IP address of the LSP. The MPLS Topology Server determines the LSP ID during postprocessing discovery. Also, during postprocessing discovery, the MPLS Topology Server determines the name of the destination PE device by traversing the HostedBy relationship of the LSP ID IP object to the device.