Pseudowire Emulation Edge to Edge (pwe3)
----------------------------------------
Charter
Last Modified: 2010-03-25
Current Status: Active Working Group
Chair(s):
Matthew Bocci <matthew.bocci@alcatel-lucent.com>
Andrew Malis <andrew.g.malis@verizon.com>
Routing Area Director(s):
Stewart Bryant <stbryant@cisco.com>
Adrian Farrel <adrian.farrel@huawei.com>
Routing Area Advisor:
Stewart Bryant <stbryant@cisco.com>
Technical Advisor(s):
David Black <black_david@emc.com>
Secretary(ies):
David Sinicrope <david.sinicrope@ericsson.com>
Mailing Lists:
General Discussion:pwe3@ietf.org
To Subscribe: pwe3-request@ietf.org
In Body: subscribe your_email_address
Archive: http://www.ietf.org/mail-archive/web/pwe3/index.html
Description of Working Group:
Network transport service providers and their users are
seeking to rationalize their networks by migrating their
existing services and platforms onto IP or MPLS enabled
IP packet switched networks (PSN). This migration requires
communications services that can emulate the essential
properties of traditional communications links over a PSN.
Some service providers wish to use MPLS technology to
replace existing transport network infrastructure, relying
upon pseudowire technology is an integral component of
these network convergence architectures.
Pseudowire Emulation Edge to Edge (PWE3) will specify the
encapsulation, transport, control, management, interworking
and security of services emulated over IETF-specified PSNs.
A pseudowire emulates a point-to-point or point-to-multipoint
link, and provides a single service which is perceived by
its user as an unshared link or circuit of the chosen
service. It is not intended that an emulated service will
be indistinguishable from the service that is being emulated.
The emulation need only be sufficient for the satisfactory
operation of the service. Emulation necessarily involves a
degree of cost-performance trade-off. In some cases it may
be necessary to design more than one emulation mechanism in
order to resolve these design conflicts. All emulated service
definitions must include an applicability statement describing
the faithfulness of the emulation.
Switching, multiplexing, modification or other operation on
the traditional service, unless required as part of the
emulation, is out of the scope of the PWE3 WG.
PWE3 will make use of existing IETF-specified mechanisms
unless there are technical reasons why the existing mechanisms
are insufficient or unnecessary.
PWE3 operates "edge to edge" and will not exert control on
the underlying PSN, other than to use any existing QoS or
path control mechanism to provide the required connectivity
between the endpoints of the PW.
PWE3 will co-ordinate this with the AVT and TICTOC WGs.
Where AVT or TICTOC require extensions to PWs to support
time or frequency transfer this work will be undertaken by
the PWE3 WG in co-ordination with the these WGs.
A PW operating over a shared PSN does not necessarily have
the same intrinsic security as a dedicated, purpose built,
network. In some cases this is satisfactory, while in other
cases it will be necessary to enhance the security of the PW
to emulate the intrinsic security of the emulated service.
PW specifications MUST include a description of how they
are to be operated over a shared PSN with adequate security.
PWE3 will work with the MPLS, L2VPN and other relevant WGs
for definitions of common solutions for the secure operation
of pseudowires.
Whilst a service provider may traffic engineer their network
in such a way that PW traffic will not cause significant
congestion, a PW deployed by an end-user may cause
congestion of the underlying PSN. Suitable congestion
avoidance mechanisms are therefore needed to protect the
Internet from the unconstrained deployment of PWs. Congestion
avoidance may be more difficult with P2MP pseudowires than
P2P pseudowires. The WG will consider both cases.
PWE3 will work closely with the L2VPN WG to ensure a clear
demarcation is defined for where PWE3 stops and L2VPN starts,
in particular in defining point-multipoint (P2MP) PWs.
PWE3 will work with MPLS and L2VPN to enhance the OAM suite
for transport applications. PWE3 will coordinate very closely
with any WG that is responsible for protocols which PWE3
intends to extend (e.g., the MPLS WG for LDP), as well as
foster interaction with WGs that intend to extend PWE3
protocols.
The IETF PWE3 WG is the design authority for pseudo-wire
over IP/MPLS PSN technology. An entity or individual that
wishes to propose extensions or changes to this technology
must bring the corresponding proposals to the PWE3 WG that
would treat them via a process similar to one described in
RFC 4929 for the MPLS/GMPLS change process.
WG Objectives:
Specify the following PW types:
Most of the initial specific PW types have been specified
(e.g., Frame Realy, Ethernet, ATM). Investigation into
and specification of a "generic PW" type and/or MPLS PW
should be undertaken.
PWE3 will specify a PW type for the special case where the
access service payloads at both ends are known to consist
entirely of IP packets. PWE3 will not specify mechanisms
by which a PW connects two different access services
unless the Network Layer protocol is IP or MPLS.
Specify the control and management functions of chartered PW
types, to include PW setup, configuration, maintenance and
tear-down. The PWE3 WG will do this in its entirety for
MPLS PSNs, and the L2TPEXT WG will develop the L2TP specifics
for L2TPv3-based PWs.
Specify Operations and Management (OAM) mechanisms for all
PW types, suitable for operation over both IP/L2TPv3 and
MPLS PSNs, and capable of providing the necessary
interworking with the OAM mechanisms of the emulated
service.
Define requirements for and mechanisms to provide
interconnection of PWs (to include inter-domain PWs).
Define requirements for and mechanisms to provide
protection and restoration of PWs.
Publish document outlining PW-specific congestion avoidance
and response guidelines.
Publish document outlining PW-specific security
considerations.
Specify requirements and mechanisms for P2MP functionality
for PWs. This work will be coordinated with the L2VPN and
MPLS working groups.
Publish requirements and specification for PW to take
advantage of multiple PSN paths that exist between PEs.
Publish requirements and specification for enhanced OAM.
Include extensions to the PWE3 protocols and RFCs
necessary to create an MPLS Transport Profile (MPLS-TP).
The work on the MPLS TP needs to be coordinated between
three primary working groups (MPLS, PWE3, L2VPN and CCAMP) that
are chartered to do MPLS TP work.
Goals and Milestones:
Done PWE3 WG started, organize editing teams.
Done Hold interim meeting, including discussion of priority of
service-specific documents and consider pruning some
deliverables
Done Accept drafts of service-specific documents as WG items
Done PW Requirements Document Last Call
Done TDM Circuit Documents Last Call
Done ATM Documents Last Call
Done Ethernet Documents Last Call
Done Fragmentation LC
Done TDM Requirements LC
Done SONET Documents Last Call
Done TDM Documents Last Call
Done Frame Relay Documents Last Call
Done FCS retention Last Call
Done Multi-Segment PW Requirements LC
Done VCCV LC
Done PWE3 Services MIBs LC
Done PPP/HDLC PW LC
Done Wildcard FEC LC
Done TDM Signaling LC
Jul 2008 Multi-Segment Architecture LC
Done Basic Pseudowire MIBs LC
Sep 2008 Fiber Channel Encap LC
Sep 2008 PW OAM Mapping LC
Sep 2008 Congestion Framework LC
Oct 2008 Multi-Segment PW LC
Dec 2008 PW Protection and Restoration Requirements LC
Dec 2008 PW Congestion Response LC
Dec 2008 Generic PW Requirements
Jan 2009 Dynamic MS PW LC
Mar 2009 PW Protection and Restoration Architecture
Mar 2009 Multipath PW LC
Mar 2009 Generic Associated Channel Header LC
Apr 2009 MPLS PW LC
Jul 2009 PW Protection and Restoration LC
Jul 2009 Multisegment PW MIB
Jul 2009 Congestion Solution LC
Jul 2009 Security Considerations LC
Jul 2009 P2MP Requirements LC
Dec 2009 Enhanced PW OAM
Dec 2009 VCCV Extensions for MPLS-TP
Dec 2009 Tandem Connection Monitoring for PWs
Internet-Drafts:
Posted Revised I-D Title <Filename>
------ ------- --------------------------------------------
Aug 2002 Mar 2010 <draft-ietf-pwe3-cep-mib-13.txt>
SONET/SDH Circuit Emulation Service Over Packet (CEP)
Management Information Base (MIB) Using SMIv2
Sep 2004 Mar 2010 <draft-ietf-pwe3-oam-msg-map-12.txt>
Pseudowire (PW) OAM Message Mapping
Jul 2005 Apr 2010 <draft-ietf-pwe3-segmented-pw-14.txt>
Segmented Pseudowire
Mar 2006 Feb 2010 <draft-ietf-pwe3-fc-encap-10.txt>
Encapsulation Methods for Transport of Fibre Channel frames
Over MPLS Networks
May 2007 Jun 2009 <draft-ietf-pwe3-mpls-transport-04.txt>
Application of Ethernet Pseudowires to MPLS Transport Networks
Nov 2007 Jul 2009 <draft-ietf-pwe3-vccv-bfd-07.txt>
Bidirectional Forwarding Detection (BFD) for the Pseudowire
Virtual Circuit Connectivity Verification (VCCV)
Feb 2008 May 2010 <draft-ietf-pwe3-redundancy-bit-03.txt>
May 14, 2010 Pseudowire Preferential Forwarding Status Bit
Mar 2008 May 2010 <draft-ietf-pwe3-redundancy-03.txt>
Pseudowire (PW) Redundancy
Sep 2008 Jan 2010 <draft-ietf-pwe3-p2mp-pw-requirements-02.txt>
Requirements for Point-to-Multipoint Pseudowire
Dec 2008 Nov 2009 <draft-ietf-pwe3-ldp-aii-reachability-03.txt>
LDP extensions for AII reachability
Feb 2009 Mar 2010 <draft-ietf-pwe3-mpls-eth-oam-iwk-02.txt>
MPLS and Ethernet OAM Interworking
Jul 2009 Jan 2010 <draft-ietf-pwe3-fat-pw-03.txt>
Flow Aware Transport of Pseudowires over an MPLS PSN
Feb 2010 Feb 2010 <draft-ietf-pwe3-static-pw-status-00.txt>
Pseudowire Status for Static Pseudowires
Request For Comments:
RFC Stat Published Title
------- -- ----------- ------------------------------------
RFC3916 I Oct 2004 Requirements for Pseudo-Wire Emulation Edge-to-Edge
(PWE3)
RFC3985 I Mar 2005 PWE3 Architecture
RFC4197 I Nov 2005 Requirements for Edge-to-Edge Emulation of Time Division
Multiplexed (TDM) Circuits over Packet Switching
Networks
RFC4385 PS Feb 2006 Pseudowire Emulation Edge-to-Edge (PWE3) Control Word
for Use over an MPLS PSN
RFC4446BCP Apr 2006 IANA Allocations for Pseudowire Edge to Edge Emulation
(PWE3)
RFC4447 PS Apr 2006 Pseudowire Setup and Maintenance using the Label
Distribution Protocol (LDP)
RFC4448 PS Apr 2006 Encapsulation Methods for Transport of Ethernet Over
MPLS Networks
RFC4553 PS Jun 2006 Structure-Agnostic Time Division Multiplexing (TDM) over
Packet (SAToP)
RFC4623 PS Aug 2006 Pseudowire Emulation Edge-to-Edge (PWE3) Fragmentation
and Reassembly
RFC4619 PS Sep 2006 Encapsulation Methods for Transport of Frame Relay Over
MPLS Networks
RFC4618 PS Sep 2006 Encapsulation Methods for Transport of PPP/High-Level
Data Link Control (HDLC) over MPLS Networks
RFC4720 PS Nov 2006 Pseudowire Emulation Edge-to-Edge (PWE3) Frame Check
Sequence Retention
RFC4717 PS Dec 2006 Encapsulation Methods for Transport of Asynchronous
Transfer Mode (ATM) over MPLS Networks
RFC4816 PS Feb 2007 Pseudowire Emulation Edge-to-Edge (PWE3) Asynchronous
Transfer Mode (ATM) Transparent Cell Transport Service
RFC4842 PS Apr 2007 Synchronous Optical Network/Synchronous Digital
Hierarchy SONET/SDH) Circuit Emulation over Packet
(CEP))
RFC4863 PS May 2007 Wildcard Pseudowire Type
RFC5003 PS Sep 2007 Attachment Individual Identifier (AII) Types for
Aggregation
RFC5087 I Dec 2007 Time Division Multiplexing over IP (TDMoIP)
RFC5086 I Dec 2007 Structure-Aware Time Division Multiplexed (TDM) Circuit
Emulation Service over Packet Switched Network (CESoPSN)
RFC5085 PS Dec 2007 Pseudowire Virtual Circuit Connectivity Verification
(VCCV) A Control Channel for Pseudowires
RFC5287 PS Aug 2008 Control Protocol Extensions for the Setup of
Time-Division Multiplexing (TDM) Pseudowires in MPLS
Networks
RFC5254 I Oct 2008 Requirements for Multi-Segment Pseudowire Emulation
Edge-to-Edge (PWE3)
RFC5542 PS May 2009 Definitions of Textual Conventions for Pseudowires (PW)
Management
RFC5602 PS Jul 2009 Pseudowire (PW) over MPLS PSN Management Information
Base (MIB)
RFC5603 PS Jul 2009 Ethernet Pseudowire (PW) Management Information Base
(MIB)
RFC5601 PS Jul 2009 Pseudowire (PW) Management Information Base (MIB)
RFC5604 PS Jul 2009 Managed Objects for Time Division Multiplexing (TDM)
over Packet Switched Networks
RFC5605 PS Jul 2009 Managed Objects for ATM over Packet Switched Networks
(PSNs)
RFC5659 I Oct 2009 An Architecture for Multi-Segment Pseudowire Emulation
Edge-to-Edge