ISIS-TE doubts.

[ramanathan rams <ramsrm@tdd.sj.nec.com>]

hi all,

             I have the following doubts in  GMPLS-IGP interaction for TE.
could u please explain me?

Normally for TE purposes we use explicit path for establishing the LSP 
tunnel. For finding out the explicit path CSPF is used.

using ISIS TE extensions, the link properties are flooded within the IGP 
area level only, it's not flooded across the entire AS. if that is the case 
if we want to establish a tunnel that spans multiple areas then the L1 
router sitting in one area does not know the properties of the links 
outside that area, so we can't compute the complete constraint based path 
from that router.  if my assumptions are  wrong, please explain me the 
correct procedure to compute the complete path which spans across multiple 
areas of an IGP.


thanks
rams.