I have posted various post of MPLS TE and everytime I receive the question why and when mpls ip is used in TE tunnel. In this post I would like to conclude when, where and why mpls ip is used in TE tunnel.
Scenarios Where MPLS IP Is Used Or Not
1. If the MP-iBGP and Tunnel destinations are different, mpls ip command is required.
2. If the MPLS TE terminates at the egress PE, no ldp/tdp is required.
3. If the MPLS TE terminates before the PE router or egress router, tag switching is required (three labels are used).