The MPLS WG Archive

["Vikas Arya" <vikas@juniper.net>]

Hi Alexander,
Plz see my opinion inline .. 


-----Original Message-----
From: owner-mpls@uu.net [mailto:owner-mpls@uu.net] On Behalf Of
Alexander Attsik
Sent: Friday, April 02, 2004 3:27 PM
To: MPLS wg
Subject: MPLS-TE questions


 I need to understand some principles of MPLS-TE, could you help me
please.

In MPLS-TE, RSVP-TE (or CR-LDP) sets up explicit routes, previously
computed by means of Constraint-Based Routing. In light of this I have
following questions:

1. Who sets the above mentioned constraints and initiates the procedure
of Constrained Shortest Path calculation?

>>>>> Service Provider (who owns B and C in the following diagram ) has
to set the constraints according to its network design. For eg.
Bandwidth requirement on TE-LSP.


2. And quite similar question:

Imagine such situation:

 A----(B---- . . . ----C)----D

B and C are edge routers of MPLS-TE domain
A and D belong to non-MPLS  areas.

A wants to communicate with D, is it possible for A to ask B for some
QoS level and thus initiate TE-LSP setup from B to C? How can A do this
(I suppose, by means of RSVP (rfc2205)).

>>>>>> "A" can not ask explicitly to initiate the TE-LSP (using
Constraint based routing). How and where (in SP network), the TE-LSP
will be setup, is again, configured by SP. Service Provider can provide
QoS services, and TE-LSP calculation and setup is internal to SP
network. Though Service Provider can configure B, such that when
(general or particular)traffic comes from A, and destined to D, it
follows a particular TE-LSP.


Thanks,
Vikas