doubts about PSC and L2SC in draft-ietf-ccamp-gmpls-architecture-00

[wesam.alanqar@mail.sprint.com]

Hi,

In the original GMPLS architecture, PSC interfaces were introduced for
the packet layer. Why in this document L2SC interfaces are introduced? 

Why do we need to introduce a new level of hierarchy?
In the original GMPLS architecture, we had PSC,TDM, LSC, FSC. In this
draft we have L2SC added.

Is this to make GMPLS more applicable for ATM and Ethernet "MPLS
capable" in addition to IP-based networks. 

Do we need to use one type of interfaces (PSC or L2SC) above the TDM
layer or we could use both?

Thanks

-----------------------------------------------------
Wesam Alanqar         Member of Technical Staff
Technology Research Group
Technology Planning & Integration Dept. (TP&I)
Sprint
9300 Metcalf Avenue, KS 66212 
Phone: 913-534-5623 Work, Fax: 913-534-3485
------------------------------------------------------
-----Original Message-----
From: Internet-Drafts [mailto:Internet-Drafts@ietf.org]
Sent: Tuesday, July 03, 2001 5:56 AM
To: IETF-Announce: .
Cc: ccamp; Internet-Drafts
Subject: I-D ACTION:draft-ietf-ccamp-gmpls-architecture-00.txt


A New Internet-Draft is available from the on-line Internet-Drafts
directories.
This draft is a work item of the Common Control and Measurement Plane
Working Group of the IETF.

      Title       : Generalized Multi-Protocol Label Switching (GMPLS) 
                          Architecture
      Author(s)   : E. Mannie et al.
      Filename    : draft-ietf-ccamp-gmpls-architecture-00.txt
      Pages       : 48
      Date        : 02-Jul-01
      
Future data and transmission networks will consist of elements such 
as routers, switches, DWDM systems, Add-Drop Multiplexors (ADMs), 
photonic cross-connects (PXCs), optical cross-connects (OXCs), etc 
that will use Generalized MPLS (GMPLS) to dynamically provision 
resources and to provide network survivability using protection and 
restoration techniques.

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