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A philosophical question about FA and FA-LSP



 

Hi,

 

I have a question to Kireti and Yakov.

 

This is from draft-ietf-ccamp-gmpls-routing-09.txt:

 

 

Traditionally, a TE link is advertised as an adjunct to a "regular"
   link, i.e., a routing adjacency is brought up on the link, and when
   the link is up, both the properties of the link used for Shortest
   Path First (SPF) computations (basically, the SPF metric) and the TE
   properties of the link are then advertised.
 
   GMPLS challenges this notion in three ways.  First, links that are
   not capable of sending and receiving on a packet-by-packet basis may
   yet have TE properties; however, a routing adjacency cannot be
   brought up on such links.  Second, a Label Switched Path can be
   advertised as a point-to-point TE link (see [LSP-HIER]); thus, an
   advertised TE link may be between a pair of nodes that don't have a
   routing adjacency with each other.  Finally, a number of links may be
   advertised as a single TE link (perhaps for improved scalability), so
   again, there is no longer a one-to-one association of a regular
   routing adjacency and a TE link.
 
   Thus we have a more general notion of a TE link.  A TE link is a
   "logical" link that has TE properties. ?
 
My question is:  can I draw a conclusion from the above that it is not required anymore for an FA to be advertised into the same instance of IGP-TE as was used for the advertising of the FA-LSP constituent TE links.
 In other words, if an LSP created by one instance of the control plane (say, L1VPN Provider) and advertised as a TE link into another instance of the control plane (say, VPN), would/should such TE link be treated 
anyhow different from the LSP advertised into the same instance of control plane.
 
Thanks,
Igor