The MPLS WG Archive

[Nhat Thanh Hoang <Nhat.T.Hoang@telia.se>]

Hi,

I Think you can find the answer at the following drafts:
http://www.ietf.org/internet-drafts/draft-ietf-mpls-rsvp-lsp-tunnel-08.txt
http://www.ietf.org/internet-drafts/draft-ietf-isis-traffic-02.txt

As I know contraint-based (the constraints such as bandwidth, link colors)
signaled LSPs can only be established within one IS-IS area, because the
traffic-engineering database is only propagating within an area. But, I
think there are RSVP-TE implementations (are vendor dependent)that support
inter-area LSPs by explicitly and strictly point out hop-by-hop along the
LSP you want to establsih and without the constraints: bandwidth and
linkcoloring.
See also the comment line below:

-----Original Message-----
From: Dirk Maeckelberghe [mailto:Dirk.Maeckelberghe@swift.com]
Sent: den 30 april 2001 14:53
To: mpls@UU.NET
Subject: MPLS TE question


Hello,

Can you point me to the right references or help answer underneath
questions.

I need to know if I can use the TE extensions to setup an LSP using RSVP-TE
( cross area )  in case my IGP is  hierarchical IS-IS (
L1 and L2 ).
Can I assume that summarization happens at area boundaries and that the
detailed TE info does not get propagated inside the area ?

- Yes, You are right about that.

This is case A to B where A,B LER and L2A and L2B LSR

A - area 1 - L2A ---- L2X --- L2B - area 2 - B


If now I am only extending my MPLS cloud to the L2 routers ( L2A - L2B are
now LER ), A and B are NON-MPLS routers,
can I then use the TE extensions of IS-IS to do TE between the L2A and L2B.
I understand that the L2 routers only  form L2 adjacencies, are the TE
extensions communicated between them ?

- I'm not sure if I understand you correctly, and I suppose that now you
mean the changed scenario is L2A, L2X and L2B are Level 2 MPLS-capable
routers, then the answer to your question is YES.

- If I'm wrong please correct me.

- I hope it would help something

Cheers,
/Nhat Thanh

Telia Research AB

A - area 1 - L2A ---- L2X --- L2B - area 2 - B

Thanks,

Dirk