Requirements analysis

For an LSP, the outgoing label specified on an LSR must be identical with the incoming label specified on the downstream LSR.

LSPs are unidirectional. You must configure an LSP for each direction of the data forwarding path.

A route to the destination address of the LSP must be available on the ingress and egress nodes, but it is not needed on transit nodes. Therefore, you do not need to configure a routing protocol to ensure IP connectivity among all switches.