PWE3 Working Group
   Internet Draft                                              A. Malis
   draft-ietf-pwe3-cell-transport-01.txt                        Tellabs
   Expires: February 2005                                    L. Martini
                                                          Cisco Systems
                                                             J. Brayley
                                                  Laurel Networks, Inc.
                                                               T. Walsh
                                                    Lucent Technologies
                                                            August 2004


                PWE3 ATM Transparent Cell Transport Service


IPR Statement

   By submitting this Internet-Draft, I certify that any applicable
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   or will be disclosed, and any of which I become aware will be
   disclosed, in accordance with RFC 3668.

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Abstract

   The document describes a transparent cell transport service that
   makes use of the "N-to-one" cell relay mode for PWE3 ATM cell
   encapsulation described in [ATM-ENCAPS].

Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC-2119 [1].



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1. Intellectual Property Statement

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
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   on the procedures with respect to rights in RFC documents can be
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   this standard.  Please address the information to the IETF at ietf-
   ipr@ietf.org.

2. Introduction

   This transparent cell transport service allows migration of ATM
   services to a PSN without having to provision the ATM subscriber or
   customer edge (CE) devices.  The ATM CEs will view the ATM
   transparent cell transport service as if they were directly connected
   via a TDM leased line.  This service is most likely to be used as an
   internal function in a ATM service provider's network as a way to
   connect existing ATM switches via a higher speed PSN, or to provide
   ATM "backhaul" services for remote access to existing ATM networks.

3. Transparent Cell Transport Definition

   The transparent port service is a natural application of the "N-to-
   one" cell relay mode for PWE3 ATM encapsulation described in [2].

   The ATM transparent port service emulates connectivity between two
   remote ATM ports. This service is useful when one desires to connect
   two CEs without processing or switching at the VPC or VCC layer.  The
   ingress PE discards any idle/unassigned cells received from the
   ingress ATM port, and maps all other received cells to a single
   Pseudo Wire, using the "N-to-one" cell relay encapsulation in [2].

   The egress PE doesn't change the VPI, VCI, PTI, or CLP bits when it
   sends these cells on the egress ATM port.  Therefore the transparent
   port service appears to emulate an ATM transmission convergence layer
   connection between two ports.  However, since the ingress PE discards
   idle/unassigned cells, this service benefits from statistical
   multiplexing bandwidth savings.

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4. Security Considerations

   This draft does not introduce any new security considerations beyond
   those in [2], and in [3].


5. Normative References

  [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
      Levels", BCP 14, RFC 2119, March 1997.

  [2] Martini, L., et al, "Encapsulation Methods for Transport of ATM
      Cells/Frame Over IP and MPLS Networks", work in progress, draft-
      ietf-pwe3-atm-encap-06.txt, July 2004.

  [3] Martini, L., et al, "Pseudowire Setup and Maintenance using LDP",
      work in progress, draft-ietf-pwe3-control-protocol-08.txt, July
      2004.


6. Full Copyright Statement

  Copyright (C) The Internet Society (2004).  This document is subject
  to the rights, licenses and restrictions contained in BCP 78 and
  except as set forth therein, the authors retain all their rights.

  This document and the information contained herein are provided on an
  "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
  OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
  ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
  INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
  INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
  WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


Acknowledgments

   The authors would like to thank the members of the PWE3 working group
   for their assistance on this draft.


Author's Addresses

   Andrew G. Malis
   Tellabs
   90 Rio Robles Drive
   San Jose, CA 95134
   Email: Andy.Malis@tellabs.com




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PWE3 ATM Transparent Cell Transport Service                August 2004

   Luca Martini
   Cisco Systems, Inc.
   9155 East Nichols Avenue, Suite 400
   Englewood, CO, 80112
   e-mail: lmartini@cisco.com

   Jeremy Brayley
   Laurel Networks, Inc.
   Omega Corporate Center
   1300 Omega Drive
   Pittsburgh, PA 15205
   Email: jbrayley@laurelnetworks.com

   Tom Walsh
   Lucent Technologies
   1 Robbins Road
   Westford, MA 01886 USA
   Email: tdwalsh@lucent.com




































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