The SR-TE auto-LSP feature allows the auto-creation of an SR-TE mesh LSP and for an SR-TE one-hop LSP.
The SR-TE mesh LSP feature specifically binds an LSP template of a new type, mesh-p2p-srte, with one more prefix list. When the TE database discovers a router, which has a router ID matching an entry in the prefix list, it triggers MPLS to instantiate an SR-TE LSP to that router using the LSP parameters in the LSP template.
The SR-TE one-hop LSP feature specifically activates an LSP template of a new type, one-hop-p2p-srte. In this case, the TE database keeps track of each TE link which comes up to a directly connected IGP neighbor. It then instructs MPLS to instantiate an SR-TE LSP with the following parameters:
the source address of the local router
an outgoing interface matching the interface index of the TE-link
a destination address matching the router-id of the neighbor on the TE link
In both types of SR-TE auto-LSP, the router’s hop-to-label translation or local CSPF computes the label stack required to instantiate the LSP path.