Internet Draft Don Fedyk, Nortel
Category: Informational Lou Berger, LabN
Expiration Date: May 9, 2008 Loa Andersson, Acreo AB
November 9, 2007
GMPLS Ethernet Label Switching Architecture and Framework
draft-gmpls-ethernet-arch-00.txt
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Abstract
There has been significant recent work in increasing the capabilities
of Ethernet switches. As a consequence, the role of Ethernet is
rapidly expanding into "transport networks" that previously were the
domain of other technologies such as SONET/SDH TDM and ATM. This
document defines an architecture and framework for a GMPLS based
control plane for Ethernet in this "transport network" capacity.
GMPLS has already been specified for similar technologies. Some
additional extensions to the GMPLS control plane are needed and this
document provides a framework for these extensions.
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Contents
1 Introduction .............................................. 3
2 Background ................................................ 5
2.1 Ethernet Switching ........................................ 5
2.2 Operations, Administration, and Maintenance (OAM) ......... 7
2.3 Terminology ............................................... 8
2.3.1 Concepts .................................................. 8
2.3.2 Acronyms .................................................. 9
2.4 Ethernet and MPLS similarities and differences ............ 10
3 Framework ................................................. 10
4 GMPLS Routing and Addressing Model ........................ 12
4.1 GMPLS Routing ............................................. 13
4.2 Control Plane Network ..................................... 13
5 P2P Signaling ............................................ 13
6 Link Management .......................................... 14
7 Path Computation and Selection ............................ 15
8 Multiple Domains .......................................... 16
9 Security Considerations ................................... 16
10 IANA Considerations ....................................... 16
11 References ................................................ 16
11.1 Normative References ...................................... 16
11.2 Informative References .................................... 16
12 Acknowledgments ........................................... 18
13 Author's Addresses ........................................ 18
14 Full Copyright Statement .................................. 18
15 Intellectual Property ..................................... 19
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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 [RFC2119].
Document History
This is the initial draft of this document.
1. Introduction
There has been significant recent work in increasing the capabilities
of Ethernet switches. As a consequence, the role of Ethernet is
rapidly expanding into "transport networks" that previously were the
domain of other technologies such as SONET/SDH TDM and ATM. The
evolution and development of Ethernet capabilities in these areas is
a very active and ongoing process.
Multiple organizations have been active in extending Ethernet
technology. This activity has taken place in the IEEE 802.1 Working
Group, the ITU and the MEF. These groups have been focusing on
Ethernet forwarding, Ethernet management plane extensions and the
Ethernet Spanning Tree Control Plane, but not an explicitly routed,
constraint based control plane.
In the forwarding plane context, extensions have been, or are being,
defined to support different Ethernet forwarding models, protection
modes and service interfaces. Examples of such extensions include
[802.1ah], [802.1Qay], [G.8011] and [MEF.6]. The provider extensions
allow for greater flexibility in the forwarding plane. In the
802.1Qay case the extensions allow for a departure from forwarding
based on Ethernet spanning tree. The greater flexibility in
forwarding is achieved through the addition of a "provider" address
space.
This document is a framework for GMPLS Ethernet Label switching
(GELS). It will be followed by technology specific documents. GELS
will require more than one switching type, and the GMPLS procedures
that will need to be changed is dependent on switching, and thus will
be covered in the technology specific documents.
In the new provider bridge model developed in the IEEE802.1ad-project
and amended to the IEEE802.1Q standard [802.1Q], an extra VLAN
identifier (VID) is added. This VLAN is referred to as the Service
VID, (S-VID and is carried in a Service TAG (S-TAG). In provider
backbone bridges (PBB) [802.1ah] a backbone VID (B-VID) and B-MAC
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header with a Service Instance (I-TAG) encapsulates a customer
Ethernet frame or a service Ethernet frame. An example of Ethernet
protection extensions can be found in [G.8031]. In the IEEE802.1Q
standard the terms Provider Backbone Bridges (PBB) and Provider
Backbone Bridged Network (PBBN) is used in the context of these
extensions.
Ethernet operations, administration, and maintenance (OAM) is another
important area that is being extended to enable provider Ethernet
services. Related extensions can be found in [802.1ag] and [Y.1731].
The Ethernet forwarding and management plane extensions explicitly
allow for the disabling of standard Ethernet spanning tree but do not
define an explicitly routed, constraint based control plane. The
IEEE802.1, in [802.1Qay], works on an new amendment that explicitly
allows for traffic engineering of Ethernet forwarding paths.
The IETF chartered the GMPLS work to specify a common control plane
for physical path and core tunneling technologies for the Internet
and telecommunication service providers. The GMPLS architecture is
specified in RFC3945 [RFC3945]. The protocols specified for GMPLS
have been used to control "Transport Networks", e.g. Optical and TDM
networks.
This document provides a framework for use of GMPLS to control
"transport" Ethernet. The GMPLS architecture already handles a number
of transport technologies but Ethernet adds a few new constraints
that must be documented. Some additional extensions to the GMPLS
control plane are needed and this document provides a framework for
these extensions.
This document introduces and explains the concept of an Ethernet
Label Switched Path (Eth-LSP). The data plane aspects of Eth-LSPs are
outside the scope of this document and IETF activities.
The intent of this document is to reuse and align with as much of the
GMPLS protocols as possible. For example reusing the IP control
plane addressing allows the existing signaling, routing, LMP and path
computation to be used as specified. Additions are made only to
accommodate features of Ethernet that are not already supported by
GMPLS. The GMPLS protocols support a set of tools for hierarchical
LSPs as well as contiguous LSPs. GMPLS specific protocol mechanisms
support a variety of networks from peer to peer to UNIs and NNIs.
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2. Background
This section provides background to the types of switching and
services that are supported within the defined framework. The former
is particularly important as it identifies the switching functions
that GMPLS will need to represent and control. The intent is for this
document to allow for all standard forms of Ethernet switching and
services.
The material presented in this section is based on the on-going work
taking place in the IEEE 802.1 Working Group, the ITU and the MEF.
This section references and, to some degree, summarizes that work.
This section is not a replacement for, or an authoritative
description of that work.
2.1. Ethernet Switching
In Ethernet switching terminology, the bridge relay is responsible
for forwarding and replicating the frames. Bridge relays forward
frames based on the header fields: Virtual Local Area Network (VLAN)
Identifiers (VID) and Destination Media Access Control (DMAC)
address. PBB [802.1ah] has also introduced a Service Instance tag (I-
TAG). Across all the Ethernet extensions (already referenced in the
Introduction), multiple forwarding functions, or service interfaces,
have been defined using the combination of VIDs, DMACs, and I-TAGs.
PBB [802.1ah] provides a breakdown of the different types of Ethernet
switching services. Figure 1 reproduces this breakdown.
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Service Types
_,,-' | '--.._
_,.-'' | `'--.._
_,.--' | `'--..
Port based S-tagged I-tagged
_,- -.
_.' `.
_,' `.
one-to-one bundled
_.- =.
_.-' ``-.._
_.-' `-..
many-to-one all-to-one
|
|
|
Transparent
Figure 1: Ethernet Switching Service Types
The types are defined in Clause 25 of [802.1ah], and are consistent
with the definitions of Ethernet services supported in [G.8011] and
[MEF.6]. To summarize the definitions:
o Port based
This is a frame based service that supports specific frame types,
no Service VLAN tagging, with MAC address based switching.
o S-tagged
There are multiple Service VLAN tag (S-tag) aware services,
including:
+ one-to-one
In this service, each VLAN identifier (VID) is mapped into a
different service.
+ Bundled
Bundled S-tagged service supports the mapping of multiple VIDs
into a single service and include:
* many-to-one
In this frame based service, multiple VIDs are mapped into the
same service.
* all-to-one
In this frame based service, all VIDs are mapped into the same
service.
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- transparent
This is a special case, all frames are mapped from a single
incoming port to a single destination Ethernet port.
o I-tagged
The edge of a PBBN consists of a combined backbone relay (B-
component relay) and service instance relay (I-component relay).
An I-Tag contains a service identifier (24 bit I-SID) and priority
markings as well as some other flags. An I-Tagged service is
typically between the edges of the PBBN and terminated at each edge
on an I-component that faces a customer port so the service is
often not visible except at the edges. However since the I-
component relay involves a distinct relay it is possible to have a
visible I-Tagged Service by separating the I component relay from
the B-component relay. Two examples where it makes sense to do
this are: an I-Tagged service between two PBBNs and as an
attachment to a customer's Provider Instance Port.
In general, the different types determine which of the Ethernet
header fields are used in the forwarding/switching function, e.g. VID
only or VID and DMACs. The types may also require the use of
additional Ethernet headers or fields. Services defined for UNIs tend
to use the headers on a hop-by-hop basis.
In most cases for bridging, the header fields cannot be changed hop-
by-hop, but some translations of VID field values are permitted
typically at the edges. Again, while not specifically described in
802.1ah, the Ethernet services being defined in the context of
[MEF.6] and [G.8011] also fall into the types defined in Figure 1.
Across all service types, the Ethernet data plane is bi-directional
congruent. This means that the forward and reverse paths share the
exact same set of nodes, ports and bi-directional links. This
property is fundamental. The 802.1 group has defined maintained this
bi-directional congruent property in the definition of Connectivity
Fault Management (CFM) which is part of the overall Operations
Administration and Management (OAM) capability.
2.2. Operations, Administration, and Maintenance (OAM)
Robustness is enhanced with the addition of data plane OAM to provide
both fault and performance management.
For the Eth LSP unicast mode of behavior, the hardware performs
unicast packet forwarding of known MAC addresses exactly as Ethernet
currently operates. The OAM currently defined, [802.1ag] and [Y.1731]
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can also be reused without modification of the protocols.
OAM relies on domain wide path identifiers, for data plane
forwarding, utilizing the 60 bit unique connection ID (VID/DMAC).
Determining a broken path or misdirected packet in this case relies
on the connection ID not being altered on the Eth-LSP. These
identifiers are independent of the control plane so it works equally
well for provisioned or GMPLS controlled paths.
Ethernet OAM currently consists of:
Defined in both [802.1ag & Y.1731]:
- CCM/RDI: Connectivity Check, Remote Defect Indication
- LBM/LBR: Loopback Message, Loopback Reply
- LTM/LTR: Link trace Message, Link trace Reply
- VSM/VSR: Vendor-specific extensions Message/Reply
Additionally defined in [Y.1731]:
- AIS: Alarm Indication Signal
- LCK: Locked Signal
- TST: Test
- LMM/LMR: Loss Measurement Message/Reply
- DM/DMM/DMR: Delay Measurement
- EXM/EXR: Experimental
- APS, MCC: Automatic Protection Switching, Maintenance
Communication Channel
- Placeholders for ITU other standards
With some Eth-LSP label formats bidirectional transactions (e.g.
LBM/LBR) and reverse direction transactions MAY have a different VID
for each direction. Currently Y.1731 & 802.1ag makes no
representations with respect to this but work us underway to address
this in PBB-TE [802.1Qay].
2.3. Terminology
2.3.1. Concepts
The following are basic Ethernet and GMPLS terms:
o Asymmetric Bandwidth
This term refers to the property of a Bi-directional LSP may have
differing bandwidth allocation in each direction.
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o Bi-directional Congruent LSP
This term refers to the property that an LSP shared the same
nodes, ports and links. Ethernet data planes are normally bi-
directional congruent.
o Shared forwarding
Shared forwarding is a property of a data path where a single
forwarding entry (VID + DMAC) may be used for frames from
multiple sources (SMAC). Shared forwarding does not change any
data plane behavior it saves forwarding information base (FIB)
entries only. From all other aspects it behaves as if there were
multiple FIB entries.
o In-band GMPLS Signaling
In-band GMPLS Signaling is IP based signaling on the native
Ethernet links encapsulated by a single hop Ethernet header.
Logical links that use a dedicated VID on the same physical links
would be considered In-band signaling.
o Out-of-band GMPLS Signaling is IP based signaling between
Ethernet switches that uses some other links other than the
Ethernet data plane links. Out of band signaling typically shares
a different fate from the data links.
o Contiguous Eth-LSP is an Eth-LSP that maps one to one with and
LSP at a domain boundary. Stitched LSP are contiguous LSPs.
o Hierarchical Eth-LSPs are Eth-LSPs that are encapsulated and
tunneled either individually or bundled with other LSPs through a
domain.
2.3.2. Acronyms
The following acronyms are used in this document:
CFM Connectivity Fault Management
DMAC Destination MAC Address
CCM Continuity Check Message
Eth-LSP Ethernet Label Switched Path
I-SIDService Idenitifier
LMP Link Management Protocol
MAC Media Access Control
MP2MP Multipoint to multipoint
NMS Network Management System
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OAM Operations, Administration and Maintenance
PBB Provider Backbone Bridges [802.1ah]
PBB-TE Provider Backbone Bridges Traffic Engineering
[802.1Qay]
P2P Point to Point
P2MP Point to Multipoint
QoS Quality of Service
SMAC Source MAC Address
S-TAG A service TAG defined in the 802.1 Standard
[802.1Q]
TE Traffic Engineering
TAG An Ethernet short form for a TAG Header
TAG Header An extension to an Ethernet frame carrying
priority and other information.
TSpec Traffic specification
VID VLAN Identifier
VLAN Virtual LAN
2.4. Ethernet and MPLS similarities and differences
Ethernet is similar to MPLS in that there is a default payload type.
In MPLS the default payload is either another MPLS label or an IP
packet. The IP packet may carry any type of service IP carries.
Ethernet assumes an Ethernet frame as the default payload. The actual
service can be anything that Ethernet carries.
In MPLS pseudo wires where other types of payloads are used natively
the payload may be identified implicitly or explicitly by using a
control word removing the need for the IP header.
Similarly, in Ethernet the option to carry other payloads by using
either implicit or explicit means is being discussed.
Ethernet bridging is different from MPLS in that while the switching
decision is taken on whatever is defined as the Ethernet label, that
label is usually not swapped at each hop.
3. Framework
As defined in the (GMPLS) Architecture [RFC3945], the GMPLS control
plane can be applied to a technology by controlling the data plane
and switching characteristics of that technology. The architecture
includes a clear separation between a control plane and a data plane.
Control plane and data plane separation allows the GMPLS control
plane to remain architecturally and functionally unchanged while
controlling different technologies. The architecture also requires
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IP connectivity for the control plane to exchange information, but
does not otherwise require an IP data plane.
All aspects of GMPLS, i.e., addressing, signaling, routing and link
management, may be applied to Ethernet switching. GMPLS can provide
control for traffic engineered and protected Ethernet service paths.
This document defines the term "Eth-LSP" to refer to Ethernet service
paths that are controlled via GMPLS. As is the case with all GMPLS
controlled services, Eth-LSPs can leverage common traffic engineering
attributes such as:
- bandwidth profile;
- priority level;
- preemption characteristics;
- protection/resiliency capability;
- routing policy, such as an explicit route;
- bi-directional service;
- end-to-end and segment protection;
- hierarchy
The bandwidth profile may be used, to set committed information rate
and peak information rate, and policies based on either under-
subscription or over-subscription. Services covered by this
framework MUST have a TSpec that follows the Ethernet Traffic
parameters defined in [ETH-TSPEC].
In applying GMPLS to Ethernet, GMPLS will be extended to work with
the Ethernet data plane and switching functions. The definition of
GMPLS support for Ethernet is multi-faceted due to the different
forwarding/switching functions inherent in the different service
types discussed in Section 2.1. In general, the header fields used in
the forwarding/switching function, e.g. VID and DMAC, can be
characterized as a data plane label. In some circumstances these
fields will be constant along the path of the Eth-LSP, and in others
they may vary hop-by-hop or at certain interfaces only along the
path. In the case where the "labels" must be forwarded unchanged,
there are a few constraints on the label allocation that are similar
to some other technologies such as lambda labels.
The general characteristics of the IEEE 802.1Q [802.1Q] data plane
are left unchanged. The VID is used as a "filter" pointing to a
particular forwarding table, and if the DMAC is found in that
forwarding table the forwarding decision is taken based on the DMAC.
When forwarding using an Ethernet spanning tree, if the DMAC is not
found the frame is broadcast over all outgoing interfaces for which
that VID is defined. This valid MAC checking and broadcast supports
Ethernet learning. The amendment to IEEE802.1Q that is specified
under IEEE802.1Qay allows for turning off learning and hence this
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broadcast mechanism. A special case is when a VID is defined for only
two ports on one bridge, in that case all frames with that VID
received over one of these ports are forward over the over port.
This document does not define any specific format for an Eth-LSP
label. Rather, it is expected that service specific documents will
define any signaling and routing extensions needed to support that
specific Ethernet service. Depending on the requirements of a
service, it may be necessary to define multiple GMPLS extensions,
e.g., label formats, switching types, and Traffic Engineering (TE)
routing extensions. It is expected that all such extensions will be
consistent with this document. It is expected that there will be no
case where an Eth-LSP will be signaled, or an Eth-LSP supporting
interface will be represented, using the L2SC switching
type/capability. A new switching type/capability is required to
avoid any potential current usage of the L2SC switching
type/capability in support of Ethernet.
For discussion purposes, we decompose the problem of applying GMPLS
into the functions of Routing, Signaling, Link Management and Path
Selection. It is possible to use some functions of GMPLS alone or in
partial combinations. In most cases using all functions of GMPLS
leads to less operational overhead than partial combinations.
4. GMPLS Routing and Addressing Model
The GMPLS Routing and Addressing Model is not modified by this
document. GMPLS control for Eth-LSPs uses the Routing and Addressing
Model described in [RFC3945]. Most notably this includes the use of
IP addresses to identify interfaces and LSP end-points. It also
includes support for both numbered and unnumbered interfaces.
In the case where another address family or type of identifier is
required to support an Ethernet service, extensions may be defined to
provide mapping to an IP address. Extensions to support non-IP based
LSP identification in signaling, i.e., replacement of the IP address
in the RSVP SESSION or SENDER_TSPEC objects, are not permitted under
this framework.
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4.1. GMPLS Routing
GMPLS routing [RFC4202] is IP routing with the opaque TLV extensions
for the purpose of distributing GMPLS related TE (router and link)
information. As is always the case with GMPLS, TE information is
populated with TE resources coordinated with LMP or from
configuration if LMP is not available. The bandwidth resources of the
links are tracked as Eth-LSPs are set up. Interfaces supporting the
switching of Eth-LSPs are identified using the appropriate Interface
Switching Capabilities. As mentioned in Section 2, it will be
necessary to define one or more new Interface Switching Capabilities
to support Eth-LSPs. The L2SC Interface Switching Capabilities MUST
NOT be used to represent interfaces capable of supporting Eth-LSPs.
Interface Switching Capability specific TE information may be defined
as needed to support the requirements of a specific Ethernet
Switching Service Type.
GMPLS Routing is an optional piece but it is highly valuable in
maintaining topology and distributing the TE database for path
management and dynamic path computation.
4.2. Control Plane Network
In order for a GMPLS control plane to operate, an IP network of
sufficient capacity to handle the information exchange between the
GMPLS routing and signaling protocols is necessary.
One way to implement this is with an IGP that views each switch as a
terminated IP adjacency. In other words, IP traffic and a simple
routing table are available for the control plane but there is no
requirement for a high performance IP data plane.
This IP connectivity can be provided as a separate independent
network (out of band) or integrated with the Ethernet switches (in-
band).
5. P2P Signaling
GMPLS signaling, see [RFC3471], is well suited to the control of Eth-
LSPs and Ethernet switches. Signaling enables the ability to
dynamically establish a path from one ingress or egress node. The
signaled path may be completely static and not change for the
duration of its lifetime. However, signaling also has the capability
to dynamically adjust the path in a coordinated fashion after the
path has been established. The range of signaling options from static
to dynamic are under operator control. Standardized signaling also
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improves multi-vendor interoperability over simple management.
GMPLS signaling supports the establishment and control of
bidirectional and unidirectional data paths. Ethernet is bi-
directional by nature and the CFM has been built to leverage this.
Prior to CFM the emulation of a physical wire and the learning
requirements also mandated bi-direction connections. Given this, Eth-
LSPs MUST always use paths that share the same routes and fates. Eth-
LSPs may be either P2P or P2MP (see [RFC4875]). GMPLS signaling also
allows for full and partial LSP protection; see [RFC4872] and
[RFC4873].
Note that standard GMPLS does not support different bandwidth in each
direction of a bidirectional LSP. See [GMPLS-ASYM] if asymmetric
bandwidth bidirectional LSPs are required.
6. Link Management
Link discovery has been specified for Ethernet in [IEEE802.1AB].
However the 802.1AB capability is an optional feature and is not
necessarily operating before the Link is operational it primarily
supports the management plane. The benefits of running link discovery
in large systems are significant. Link discovery may reduce
configuration and reduce the possibility of undetected errors in
configuration as well as exposing misconnections.
In the GMPLS context, LMP [RFC4204] has been defined to support link
management and discovery features. LMP also supports the creation of
unnumbered interfaces can be automated. If LMP is not used there is
an additional provisioning requirement to add GMPLS link identifiers.
For large-scale implementations LMP would be beneficial. LMP also has
Fault Management capabilities that overlap with [IEEE802.1ag] and
[Y.1731]. It is recommended that LMP not be used for Fault
management and instead the native Ethernet methods be used.
LMP and 802.1AB are relatively independent. The LMP capability should
be sufficient to remove the need for 802.1AB but 802.1 AB can be run
in parallel or independently if desired. Figure 2 provides possible
ways of using LMP, 802.1AB and 802.1ag in combination.
Figure 2 illustrates the functional relationship of link management
and OAM schemes. It is intended that LMP would use functions of
link property correlation but that Ethernet mechanisms for OAM such
as CFM, link trace etc would be used for fault management and fault
trace.
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+-------------+ +-------------+
| +---------+ | | +---------+ |
| | | | | | | |GMPLS
| | LMP |-|<------>|-| LMP | |Link Property
| | | | | | | |Correlation
| | (opt) | |IP | | (opt) | |
| | | | | | | | Bundling
| +---------+ | | +---------+ |
| +---------+ | | +---------+ |
| | | | | | | |
| | 802.1AB |-|<------>|-| 802.1AB | |P2P
| | (opt) | |Ethernet| | (opt) | |link identifiers
| | | | | | | |
| +---------+ | | +---------+ |
| +---------+ | | +---------+ |
| | | | | | | |End to End
-----|-| 802.1ag |-|<------>|-| 802.1ag |-|-------
| | Y.1731 | |Ethernet| | Y.1731 | |Fault Management
| | | | | | | |Performance
| | | | | | | |Management
| +---------+ | | +---------+ |
+-------------+ +-------------+
Switch 1 link Switch 2
Figure 2: Logical Link Management Options
7. Path Computation and Selection
GMPLS does not specify a specific method for selecting paths or
supporting path computation. GMPLS allows for a wide ranges of
possibilities supported from very simple path computation to very
elaborate path coordination where a large number of coordinated paths
are required. The path computation could take the form of paths
being computed either on a management station with local computation
for rerouting or more sophisticated path computation servers.
Eth-LSPs may be supported using any path selection or computation
mechanism. As is the case with any GMPLS path selection function, and
common to all path selection mechanisms, the path selection process
should take into consideration Switching Capabilities and Encoding
advertised for a particular interface. Eth-LSPs may also make use of
the emerging path computation and selection work; see [PATH-COMP]
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8. Multiple Domains
This document will support the signaling of Ethernet parameters
across multiple domains supporting both contiguous Eth-LSP and
Hierarchical Ethernet LSPs. The intention is to support the GMPLS
tools of hierarchy supporting Peer to Peer models, UNIs and NNIs.
More detail will be added to the section in a later revision.
9. Security Considerations
The architecture for GMPLS controlled Ethernet assumes that the
network consists of trusted devices, but does not require that the
ports over which a UNI is defined is trusted, nor does equipment
connected to these ports need to be trusted. Access to the trusted
domain SHALL only occur through the protocols defined in the UNI or
NNI or through protected management interfaces. Where GMPLS is
applied to the control of VLAN only, the commonly known techniques
for mitigation of Ethernet DOS attacks may be required on UNI ports.
10. IANA Considerations
New values are required for signaling and error codes as indicated.
This section will be completed in a later version.
11. References
11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3471] Berger, L. (editor), "Generalized MPLS Signaling
Functional Description", January 2003, RFC3471.
[RFC4202] Kompella, K., Rekhter, Y., "Routing Extensions in
Support of Generalized MPLS", RFC 4202, October 2005
11.2. Informative References
[G.8031] ITU-T Draft Recommendation G.8031, Ethernet Protection
Switching.
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[G.8011] ITU-T Draft Recommendation G. 8011, Ethernet over
Transport - Ethernet services framework.
[RFC3945] E. Mannie, Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Architecture", RFC 3495.
[IEEE802.1AB] "IEEE Standard for Local and Metropolitan Area
Networks, Station and Media Access Control
Connectivity Discovery".
[IEEE802.1ag] "IEEE Draft Standard for Connectivity Fault
Management", work in progress.
[802.1ah] "IEEE standard for Provider Backbone Bridges", work in
progress.
[802.1Qay] "IEEE standard for Provider Backbone Bridge Traffic
Engineering", work in progress.
[802.1Q] "IEEE standard for Virtual Bridged Local Area Networks
802.1Q-2005", May 19, 2006
[RFC4204] Lang. J. Editor, "Link Management Protocol (LMP)"
RFC4204, October 2005
[MEF.6] The Metro Ethernet Forum MEF 6 (2004), "Ethernet Services
Definitions - Phase I".
[MEF.10] The Metro Ethernet Forum MEF 10 (2004), "Ethernet
Services Attributes Phase 1".
[RFC4875] Aggarwal, R. Ed., "Extensions to RSVP-TE for Point to
Multipoint TE LSPs", IETF RFC 4875, May 2007
[PATH-COMP] Farrel, A. et.al., "Path Computation Element (PCE)
Architecture", work in progress.
[RFC4872] Lang et.al., "RSVP-TE Extensions in support of
End-to-End Generalized Multi-Protocol Label Switching
(GMPLS)-based Recovery ", RFC 4872, May 2007.
[RFC4873] Berger, L. et.al.,"MPLS Segment Recovery", RFC 4873, May
2007.
[Y.1731] ITU-T Draft Recommendation Y.1731(ethoam), " OAM
Functions and Mechanisms for Ethernet based Networks ",
work in progress.
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[GMPLS-ASYM] Berger, L. et al., "GMPLS Asymmetric Bandwidth
Bidirectional LSPs", work in progress.
[ETH-TSPEC] Papadimitriou, D., "Ethernet Traffic Parameters", work
in progress.
12. Acknowledgments
There were many people involved in the initiation of this work prior
to this document. The GELS framework draft and the PBB-TE extensions
drafts were two drafts the helped shape and justify this work. We
acknowledge the work of these authors of these initial drafts:
Dimitri Papadimitriou, Nurit Sprecher, Jaihyung Cho, Dave Allan,
Peter Busschbach, Attila Takacs, Thomas Eriksson, Diego Caviglia,
Himanshu Shah, Greg Sunderwood, Alan McGuire, Nabil Bitar.
George Swallow contributed significantly to this document.
13. Author's Addresses
Don Fedyk
Nortel Networks
600 Technology Park Drive
Billerica, MA, 01821
Phone: +1-978-288-3041
Email: dwfedyk@nortel.com
Lou Berger
LabN Consulting, L.L.C.
Phone: +1-301-468-9228
Email: lberger@labn.net
Loa Andersson
Acreo, AB
Phone:+46 8 632 77 14
Email: loa@pi.se
14. Full Copyright Statement
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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
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"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
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