[f-nsp] VLL, VPLS and the point of configuring LSP's

[Remco Bressers]

Dear list,

At first, excuse my ignorance. I'm trying to get used to configuring MPLS on Brocade MLX/XMR series and all is working fine, but after reading through the manual i still have a question that is unanswered at the moment.
We are operating a network of 4 XMR routers in a ring topology with routed interfaces pointing to each-other. On these interfaces, i enabled ldp as follows :

router mpls
 policy
  traffic-eng ospf
  mpls-interface ve9
  ldp-enable
  mpls-interface ve92
  ldp-enable
!

Local, and remote VLL's are working perfectly. The manual is referring to configuring LSP's which you then use in the VPLS or VLL configuration to determine your path (vpls). I never used that before and it still is working. What is the actual advantage of configuring LSP's and using them in your VLL or VPLS configuration? I don't seem to understand it fully. If someone can explain it in a more basic way, i'd be very grateful.

Kind regards,

Remco Bressers