PWE3 Working Group Internet Draft A. Malis draft-malis-pwe3-cell-transport-00.txt Vivace Networks, Inc. Expires: April 2003 L. Martini Level 3 Communications J. Brayley Laurel Networks, Inc. T. Walsh Lucent Technologies October 2002 PWE3 ATM Transparent Cell Transport Service Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026 [1]. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. 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 [2]. Malis Expires - April 2003 [Page 1]
PWE3 ATM Transparent Cell Transport Service October 2002 Table of Contents 1. Introduction...................................................2 2. Transparent Cell Transport Definition..........................2 Security Considerations...........................................2 References........................................................3 Acknowledgments...................................................3 Author's Addresses................................................3 1. 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. 2. Transparent Cell Transport Definition The transparent port service is a natural application of the "N-to- oneö cell relay mode for PWE3 ATM encapsulation described in [3]. 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 ôN-to-oneö cell relay encapsulation in [3]. The egress PE doesnÆt 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. 3. Security Considerations This draft does not introduce any new security considerations beyond those in [3]. Malis Expires - April 2003 [Page 2]
PWE3 ATM Transparent Cell Transport Service October 2002 4. References 1 Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996. 2 Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997 3 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-00.txt, October 2002 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 Vivace Networks, Inc. 2730 Orchard Parkway San Jose, CA 95134 Email: Andy.Malis@vivacenetworks.com Luca Martini Level 3 Communications, LLC. 1025 Eldorado Blvd. Broomfield, CO, 80021 Email: luca@level3.net Jeremy Brayley Laurel Networks, Inc. 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 Malis Expires - April 2003 [Page 3]