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rfc:rfc6060

Internet Engineering Task Force (IETF) D. Fedyk Request for Comments: 6060 Alcatel-Lucent Category: Standards Track H. Shah ISSN: 2070-1721 Ciena

                                                              N. Bitar
                                                               Verizon
                                                             A. Takacs
                                                              Ericsson
                                                            March 2011
    Generalized Multiprotocol Label Switching (GMPLS) Control of
      Ethernet Provider Backbone Traffic Engineering (PBB-TE)

Abstract

 This specification is complementary to the GMPLS Ethernet Label
 Switching Architecture and Framework and describes the technology-
 specific aspects of GMPLS control for Provider Backbone Bridge
 Traffic Engineering (PBB-TE).  The necessary GMPLS extensions and
 mechanisms are described to establish Ethernet PBB-TE point-to-point
 (P2P) and point-to-multipoint (P2MP) connections.  This document
 supports, but does not modify, the standard IEEE data plane.

Status of This Memo

 This is an Internet Standards Track document.
 This document is a product of the Internet Engineering Task Force
 (IETF).  It represents the consensus of the IETF community.  It has
 received public review and has been approved for publication by the
 Internet Engineering Steering Group (IESG).  Further information on
 Internet Standards is available in Section 2 of RFC 5741.
 Information about the current status of this document, any errata,
 and how to provide feedback on it may be obtained at
 http://www.rfc-editor.org/info/rfc6060.

Copyright Notice

 Copyright (c) 2011 IETF Trust and the persons identified as the
 document authors.  All rights reserved.
 This document is subject to BCP 78 and the IETF Trust's Legal
 Provisions Relating to IETF Documents
 (http://trustee.ietf.org/license-info) in effect on the date of
 publication of this document.  Please review these documents
 carefully, as they describe your rights and restrictions with respect

Fedyk, et al. Standards Track [Page 1] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 to this document.  Code Components extracted from this document must
 include Simplified BSD License text as described in Section 4.e of
 the Trust Legal Provisions and are provided without warranty as
 described in the Simplified BSD License.
 This document may contain material from IETF Documents or IETF
 Contributions published or made publicly available before November
 10, 2008.  The person(s) controlling the copyright in some of this
 material may not have granted the IETF Trust the right to allow
 modifications of such material outside the IETF Standards Process.
 Without obtaining an adequate license from the person(s) controlling
 the copyright in such materials, this document may not be modified
 outside the IETF Standards Process, and derivative works of it may
 not be created outside the IETF Standards Process, except to format
 it for publication as an RFC or to translate it into languages other
 than English.

Table of Contents

 1. Introduction ....................................................3
    1.1. Co-Authors .................................................3
 2. Terminology .....................................................4
    2.1. PBB-TE and GMPLS Terminology ...............................5
    2.2. Conventions Used in This Document ..........................6
 3. Creation and Maintenance of PBB-TE Paths Using GMPLS ............6
    3.1. Shared Forwarding ..........................................9
    3.2. P2P Connections Procedures for Shared Forwarding ..........10
 4. Specific Procedures ............................................10
    4.1. P2P Ethernet LSPs .........................................10
         4.1.1. P2P Path Maintenance ...............................11
    4.2. P2MP Ethernet-LSPs ........................................12
    4.3. PBB-TE Ethernet Label .....................................12
    4.4. Protection Paths ..........................................13
    4.5. Service Instance Identification ...........................13
 5. Error Conditions ...............................................15
    5.1. ESP-VID-Related Errors ....................................15
         5.1.1. Invalid ESP-VID Value in the PBB-TE
                Ethernet Label .....................................15
         5.1.2. Allocated ESP-VID Range is Exhausted ...............16
    5.2. Invalid MAC Address .......................................16
 6. Security Considerations ........................................16
 7. IANA Considerations ............................................17
 8. References .....................................................17
    8.1. Normative References ......................................17
    8.2. Informative References ....................................19
 9. Acknowledgments ................................................19

Fedyk, et al. Standards Track [Page 2] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

1. Introduction

 The IEEE 802.1 Provider Backbone Bridge Traffic Engineering (PBB-TE)
 [IEEE802.1Qay] standard supports the establishment of explicitly
 routed traffic engineered paths within Provider Backbone Bridged
 (PBB) networks.  PBB-TE allows the disabling of:
  1. the Spanning Tree Protocol
  2. unknown destination address forwarding
  3. source address learning
 for administratively selected VLAN Identifiers.  With PBB-TE an
 external provisioning system or control plane can be used to
 configure static entries in the managed objects of bridges and so
 establish traffic engineered paths in the network.
 Generalized MPLS (GMPLS) [RFC3945] is a family of control plane
 protocols designed to operate in connection oriented and traffic
 engineering transport networks.  GMPLS is applicable to a range of
 network technologies including L2SC networks (Layer 2 Switching
 Capable).  The purpose of this document is to specify extensions for
 a GMPLS-based control plane to manage PBB-TE explicitly routed
 traffic engineered paths.  This specification is complementary to the
 GMPLS Ethernet Label Switching Architecture and Framework document
 [RFC5828].

1.1. Co-Authors

 This document is the result of a large team of authors and
 contributors.  The following is a list of the co-authors:
 David Allan
 Ericsson
 EMail: david.i.allan@ericsson.com
 Diego Caviglia
 Ericsson
 Via Negrone 1/A
 Genoa, Italy 16153
 EMail: diego.caviglia@ericsson.com
 Alan McGuire
 BT Group PLC
 OP6 Polaris House,
 Adastral Park, Martlesham Heath,
 Ipswich, Suffolk, IP5 3RE, UK
 EMail: alan.mcguire@bt.com

Fedyk, et al. Standards Track [Page 3] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 Nurit Sprecher
 Nokia Siemens Networks,
 GmbH & Co. KG
 COO RTP IE Fixed
 3 Hanagar St. Neve Ne'eman B,
 45241 Hod Hasharon, Israel
 EMail: nurit.sprecher@nsn.com
 Lou Berger
 LabN Consulting, L.L.C.
 Phone: +1-301-468-9228
 EMail: lberger@labn.net

2. Terminology

 In addition to well-understood GMPLS terms, this memo uses the
 following terminology from IEEE 802.1 [IEEE802.1ah] [IEEE802.1Qay]:
  1. BCB Backbone Core Bridge
  2. BEB Backbone Edge Bridge
  3. B-MAC Backbone MAC
  4. B-VID Backbone VLAN ID
  5. B-VLAN Backbone VLAN
  6. CBP Customer Backbone Port
  7. CCM Continuity Check Message
  8. CNP Customer Network Port
  9. C-MAC Customer MAC
  10. C-VID Customer VLAN ID
  11. C-VLAN Customer VLAN
  12. ESP Ethernet Switched Path
  13. ESP-MAC SA ESP Source MAC Address
  14. ESP-MAC DA ESP Destination MAC Address
  15. ESP-VID ESP VLAN ID
  16. Eth-LSP Ethernet Label Switched Path
  17. IB-BEB A BEB comprised of both I- and B-components
  18. I-SID Ethernet Service Instance Identifier
  19. TAG An Ethernet Header Field with Type and Values
  20. MAC Media Access Control
  21. PBB Provider Backbone Bridges
  22. PBB-TE Provider Backbone Bridges Traffic Engineering
  23. PIP Provider Instance Port
  24. PNP Provider Network Port
  25. PS Protection Switching
  26. P2P Point-to-Point
  27. P2MP Point-to-Multipoint
  28. SVL Shared VLAN Learning

Fedyk, et al. Standards Track [Page 4] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

  1. TESI Traffic Engineering Service Instance
  2. VID VLAN ID
  3. VIP Virtual Instance Port
  4. VLAN Virtual LAN

2.1. PBB-TE and GMPLS Terminology

 The PBB-TE specification [IEEE802.1Qay] defines some additional
 terminology to clarify the PBB-TE functions.  We repeat these here in
 expanded context to translate from IEEE to GMPLS terminology.  The
 terms "bridge" and "switch" are used interchangeably in this
 document.  The signaling extensions described here apply equally well
 to a PBB-TE-capable bridge supporting GMPLS signaling or to a GMPLS-
 capable switch supporting Ethernet PBB-TE forwarding.
  1. Ethernet Switched Path (ESP):
      A provisioned traffic engineered unidirectional connectivity
      path between two or more Customer Backbone Ports (CBPs) that
      extends over a Provider Backbone Bridge Network (PBBN).  The
      path is identified by the 3-tuple <ESP-MAC DA, ESP-MAC SA, ESP-
      VID>.  An ESP is point-to-point (P2P) or point-to-multipoint
      (P2MP).  An ESP is analogous to a (unidirectional) point-to-
      point or point-to-multipoint LSP.  We use the term Ethernet-LSP
      (Eth-LSP) for GMPLS established ESPs.
  1. Point-to-Point ESP:
      An ESP between two CBPs.  The ESP-DA and the ESP-SA in the ESP's
      3-tuple identifier are the individual MAC addresses of the two
      CBPs.
  1. Point-to-Multipoint ESP:
      An ESP among one root CBP and n leaf CBPs.  The ESP-DA in the
      ESP's 3-tuple identifier is a group MAC address identifying the
      n leaf CBPs, and the ESP-SA is the individual MAC address of the
      root.
  1. Point-to-Point PBB-TE Service Instance (P2P TESI):
      A service instance supported by two point-to-point ESPs where
      the ESPs' endpoints have the same CBP MAC addresses.  The two
      unidirectional ESPs are forming a bidirectional service.  The
      PBB-TE standard [IEEE802.1Qay] notes the following: for reasons
      relating to TE service monitoring diagnostics, operational
      simplicity, etc., the IEEE PBB-TE standard assumes that the
      point-to-point ESPs associated with a point-to-point TESI are

Fedyk, et al. Standards Track [Page 5] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

      co-routed.  Support for a point-to-point TE services that
      comprises non-co-routed ESPs is problematic, and is not defined
      in this standard.  Hence, a GMPLS bidirectional LSP is analogous
      to a P2P TE Service Instance.  We use the term "bidirectional
      Ethernet-LSP" for GMPLS-established P2P PBB-TE Service
      Instances.

2.2. 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].

3. Creation and Maintenance of PBB-TE Paths Using GMPLS

 IEEE PBB-TE is a connection-oriented Ethernet technology.  PBB-TE
 ESPs are created bridge by bridge (or switch by switch) by simple
 configuration of Ethernet forwarding entries.  This document
 describes the use of GMPLS as a valid control plane for the setup,
 teardown, protection, and recovery of ESPs and TESIs and specifies
 the required RSVP-TE extensions for the control of PBB-TE Service
 Instances.
 PBB-TE ESP and services are always originated and terminated on
 IB-Backbone Edge Bridges (IB-BEBs).  IB-BEBs are constituted of I and
 B components, this is illustrated in Figure 1.  A B-component refers
 to the structure and mechanisms that support the relaying of frames
 identified by Backbone VLANs in a Provider Backbone Bridge.  An
 I-component refers to the structure and mechanisms that support the
 relaying of frames identified by service instances (I-SIDs) in a
 Provider Backbone Bridge.  PBB and PBB-TE relay frames with added
 I-Component TAGs in the I-component and VLAN TAGs in the B-component.
 PBB and PBB-TE forward frames based on VLAN ID in the VLAN TAG (in
 the PBB case a B-VID) until the destination MAC address is supported
 locally by a B-component on this bridge indicating the destination
 has been reached.  At that point, the B-VLAN tag is removed and
 processing or forwarding on the next TAG begins (in the PBB case an
 I-Component TAG) until the I-component identified by the I-SID is
 reached.  At the I-component, the I-Component TAG is removed and the
 next Ethernet type identifies the TAG, etc.
 An Ethernet service supported by a PBB-TE TESI is always attached to
 a Customer Network Port (CNP) of the I-component.  A Service Instance
 Identifier (I-SID) is assigned for the service.  I-SIDs are only
 looked at by source and destination (edge) bridges, so I-SIDs are
 transparent to path operations and MAY be signaled.  The I- and
 B-components have internal ports that are connected via an internal
 LAN.  These internal ports are the Provider Instance Ports (PIPs) and

Fedyk, et al. Standards Track [Page 6] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 Customer Backbone Ports (CBPs).  PIPs and CBPs are not visible
 outside the IB-BEB.  ESPs are always originated and terminated on CBP
 ports and use the MAC address of that port.  The I-component
 encapsulates the service frames arriving from the CNP by adding an
 I-SID and a complete Ethernet MAC header with an ESP-MAC DA and
 ESP-MAC SA.  The B-component adds the ESP-VID.
 This document defines extensions to GMPLS to establish ESPs and
 TESIs.  As can be seen from the above, this requires configuration of
 both the I- and B-components of the IB-BEBs connected by the ESPs.
 In the GMPLS control plane, TE Router IDs are used to identify the
 IB-BEBs and Backbone Core Bridges (BCBs), and TE Links describe links
 connected to PNPs and CNPs.  TE Links are not associated with CBPs or
 PIPs.
 Note that since multiple internal CBPs may exist, an IB-BEB receiving
 a PATH message MUST be able to determine the appropriate CBP that is
 the termination point of the Eth-LSP.  To this end, IB-BEBs SHOULD
 advertise the CNP TE Links in the GMPLS control plane and RSVP-TE
 signaling SHOULD use the CNP TE Links to identify the termination
 point of Eth-LSPs.  An IB-BEB receiving a PATH message specifying one
 of its CNPs can locally determine which CBPs have internal
 connectivity to the I-component supporting the given CNP.  In the
 case that there is more than one suitable CBP, and no I-SID
 information is provided in the PATH message or previously in the
 associated Call setup, then the IB-BEB can decide freely which CBP to
 assign to the requested connection.  On the other hand, if there is
 information on the service (I-SID) that the given ESP will support,
 then the IB-BEB MUST first determine which PIP and associated CBP is
 configured with the I-SID and MUST assign that CBP to the ESP.

Fedyk, et al. Standards Track [Page 7] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

                    Backbone Edge Bridge (BEB)
   +------------------------------------------------------+
   |                    <TE - Router ID >                 |
   |                                                      |
   |  I-Component Relay             B-Component Relay     |
   | +-----------------------+    +---------------------+ |
   | |          +---+        |    |         B-VID       | |
   | |          |VIP|        |    | +---+         +---+ | | <TE Link>
   | |          +---+        |  +---|CBP|         |PNP|------
   | |                       |  | | +---+         +---+ | |
   | |  +---+          +---+ |  | |                     | |
  ------|CNP|          |PIP|----+ |                     | |
   | |  +---+          +---+ |    |                     | |
   | +-----------------------+    +---------------------+ |
   |                                                      |
   |                   PBB Edge Bridge                    |
   +------------------------------------------------------+
   ^--------Configured--------------^
                          ^-----------GMPLS or Configured------^
                Figure 1: IB-BEBs and GMPLS Identifiers
 Control  TE Router ID                     TE Router ID
 Plane       |  (TE Link)                       |
             V     |                            V
           +----+  |                         +-----+
 Data      |    |  |                         |     |
 Plane     |    |  V    label=ESP:VID/MAC DA |     |
      -----N    N----------------------------N     N----------
           |    |          PBB-TE            |     |   \ Network
           |    |                            /     |     Or
           +----+                           /+-----+     Customer
            BCB                       ESP:MAC IB-BEB     Facing
                                                         Ethernet
                                                         Ports
          Figure 2: Ethernet/GMPLS Addressing and Label Space
 PBB-TE defines the tuple of <ESP-MAC DA, ESP-MAC SA, ESP-VID> as a
 unique connection identifier in the data plane, but the forwarding
 operation only uses the ESP-MAC DA and the ESP-VID in each direction.
 The ESP-VID typically comes from a small number of VIDs dedicated to
 PBB-TE.  ESP-VIDs can be reused across ESPs.  There is no requirement
 that ESP-VIDs for two ESPs that form a P2P TESI be the same.

Fedyk, et al. Standards Track [Page 8] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 When configuring an ESP with GMPLS, the ESP-MAC DA and ESP-VID are
 carried in a generalized label object and are assigned hop by hop,
 but are invariant within a domain.  This invariance is similar to
 GMPLS operation in transparent optical networks.  As is typical with
 other technologies controlled by GMPLS, the data plane receiver MUST
 accept, and usually assigns, labels from its available label pool.
 This, together with the label invariance requirement mentioned above,
 result in each PBB-TE Ethernet Label being a domain-wide unique
 label, with a unique ESP-VID + ESP-MAC DA, for each direction.
 The following illustrates PBB-TE Ethernet Labels and ESPs for a P2P
 TESI.
    GMPLS Upstream Label          <ESP:MAC1(DA), VID1> (60 bits)
    GMPLS Downstream Label        <ESP:MAC2(DA), VID2> (60 bits)
    Upstream PBB-TE ESP 3-tuple   <ESP:MAC1, MAC2, VID1> (108 bits)
    Downstream PBB-TE ESP 3-tuple <ESP:MAC2, MAC1, VID2> (108 bits)
                         Table 1: Labels and ESPs

3.1. Shared Forwarding

 One capability of a connectionless Ethernet data plane is to reuse
 destination forwarding entries for packets from any source within a
 VLAN to a destination.  When setting up P2P PBB-TE connections for
 multiple sources sharing a common destination, this capability MAY be
 preserved provided certain requirements are met.  We refer to this
 capability as "shared forwarding".  Shared forwarding is invoked
 based on policy when conditions are met.  It is a local decision by
 label allocation at each end plus the path constraints.  Shared
 forwarding has no impact on the actual paths that are set up, but it
 allows the reduction of forwarding entries.  Shared forwarding paths
 are identical in function to independently routed paths that share a
 path from an intersecting bridge or link except they share a single
 forwarding entry.
 The forwarding memory savings from shared forwarding can be quite
 dramatic in some topologies where a high degree of meshing is
 required; however, it is typically easier to achieve when the
 connectivity is known in advance.  Normally, the originating GMPLS
 switch will not have knowledge of the set of shared forwarding paths
 rooted on the source or destination switch.
 Use of a Path Computation Element [RFC4655] or other planning style
 of tool with more complete knowledge of the network configuration is
 a way to impose pre-selection of shared forwarding with multiple
 paths using a single forwarding entry and optimizing for both

Fedyk, et al. Standards Track [Page 9] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 directions.  In this scenario, the originating bridge uses the
 LABEL_SET and UPSTREAM_LABEL objects to indicate the selection of the
 shared forwarding labels at both ends.

3.2. P2P Connections Procedures for Shared Forwarding

 The ESP-VID/ESP-MAC DA can be considered to be a shared forwarding
 identifier or label consisting of some number of P2P connections
 distinctly identified by the <ESP-MAC DA, ESP-MAC SA, ESP-VID> tuple.
 This is analogous to an LDP label merge, but in the shared forwarding
 case, the ESP header contains sufficient information to identify the
 flow to which a packet belongs.  Resources can continue to be
 allocated per LSP with shared forwarding.
 VLAN-tagged Ethernet packets include priority marking.  Priority bits
 MAY be used to indicate Class of Service (COS) and drop priority.
 Thus, traffic from multiple COSs could be multiplexed on the same
 Eth-LSP (i.e., similar to E-LSPs) and queuing and drop decisions are
 made based on the p-bits.  This means that the queue selection can be
 done based on a per-flow basis (i.e., Eth-LSP + priority) and is
 decoupled from the actual steering of the packet at any given bridge.
 A bridge terminating an Eth-LSP will frequently have more than one
 suitable candidate for sharing a forwarding entry (common
 ESP-VID/ESP-MAC DA, unique ESP-MAC SA).  It is a local decision of
 how this is performed but a good choice is a path that reduces the
 requirement for new forwarding entries by reusing common existing
 paths.
 The concept of bandwidth management still applies equally well with
 shared forwarding.

4. Specific Procedures

4.1. P2P Ethernet LSPs

 PBB-TE is designed to be bidirectional and symmetrically routed just
 like Ethernet.  That is, complete and proper functionality of
 Ethernet protocols is only guaranteed for bidirectional Eth-LSPs.  In
 this section, we discuss the establishment of bidirectional Eth-LSPs.
 Note, however, that it is also possible to use RSVP-TE to configure
 unidirectional ESPs, if the UPSTREAM_LABEL is not included in the
 PATH message.

Fedyk, et al. Standards Track [Page 10] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 To initiate a bidirectional Eth-LSP, the initiator of the PATH
 message MUST use the procedures outlined in [RFC3473] with the
 following specifics:
    1) it MUST set the LSP encoding type to Ethernet (2) [RFC3471].
    2) it MUST set the LSP switching type to "802_1 PBB-TE", value 40.
    3) it SHOULD set the Generalized Payload Identifier (G-PID) to
       Ethernet (33) [RFC3471].
    4) it MUST set the UPSTREAM_LABEL to the ESP-VID1/ESP-MAC1 tuple
       where the ESP-VID1 is administered locally for the local MAC
       address: MAC1.
    5) it SHOULD set the LABEL_SET or SUGGESTED_LABEL if it chooses to
       influence the choice of ESP-VID/ESP-MAC DA.
    6) it MAY carry an I-SID via Call/Connection ID [RFC4974].
 Intermediate and egress bridge processing is not modified by this
 document, i.e., is per [RFC3473].  However, as previously stated,
 intermediate bridges supporting the 802_1 PBB-TE switching type MUST
 NOT modify LABEL values.
 The ESP-VID1/ESP-MAC1 tuple contained in the UPSTREAM_LABEL is used
 to create a static forwarding entry in the Filtering Database of
 bridges at each hop for the upstream direction.  This behavior is
 inferred from the switching type, which is 802_1 PBB-TE.  The port
 derived from the RSVP_HOP object and the ESP-VID1 and ESP-MAC1
 included in the PBB-TE Ethernet Label constitute the static entry.
 At the destination, an ESP-VID (ESP-VID2) is allocated for the local
 MAC address: MAC2, the ESP-VID2/ESP-MAC2 tuple is passed in the LABEL
 object in the RESV message.  As with the PATH message, intermediate
 bridge processing is per [RFC3473], and the LABEL object MUST be
 passed on unchanged, upstream.  The ESP-VID2/ESP-MAC2 tuple contained
 in the LABEL object is installed in the forwarding table as a static
 forwarding entry at each hop.  This creates a bidirectional Eth-LSP
 as the PATH and RESV messages follow the same path.

4.1.1. P2P Path Maintenance

 Make-before-break procedures can be employed to modify the
 characteristics of a P2P Eth-LSP.  As described in [RFC3209], the LSP
 ID in the sender template is updated as the new path is signaled.
 The procedures (including those for shared forwarding) are identical
 to those employed in establishing a new LSP, with the extended tunnel

Fedyk, et al. Standards Track [Page 11] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 ID in the signaling exchange ensuring that double booking of an
 associated resource does not occur.
 Where individual paths in a protection group are modified, signaling
 procedures MAY be combined with Protection Switching (PS)
 coordination to administratively force PS operations such that
 modification is only ever performed on the protection path.  PS is a
 native capability of PBB-TE [IEEE802.1Qay] that can operate when two
 paths are set up between two common endpoints.

4.2. P2MP Ethernet-LSPs

 PBB-TE supports P2MP VID/Multicast MAC (MMAC) forwarding.  In this
 case, the PBB-TE Ethernet Label consists of a VID and a Group MAC
 address.  The procedures outlined in [RFC3473] and [RFC4875] could be
 adapted to signal P2MP LSPs for the source (point) to destination
 (multipoint) direction.  Each one of the branches of the P2MP Eth-LSP
 would be associated with a reverse-path symmetric and congruent P2P
 Eth-LSP.
 Complete procedures for signaling bidirectional P2MP E-LSPs are out
 of scope for this document.

4.3. PBB-TE Ethernet Label

 The PBB-TE Ethernet Label is a new generalized label with the
 following format:
     0                   1                   2                   3
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |0 0 0 0|      ESP VID          |    ESP MAC (highest 2 bytes)  |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                            ESP MAC                            |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                     Figure 3: PBB-TE Ethernet Label
 This format MUST be used for both P2P and P2MP Eth-LSPs.  For P2P
 Eth-LSPs, the fields specify a VID and a unicast MAC address;
 whereas, for P2MP Eth-LSPs, a VID and a group MAC address is carried
 in the label.  The PBB-TE Ethernet Label is a domain-wide unique
 label and MUST be passed unchanged at each hop.  This has similarity
 to the way in which a wavelength label is handled at an intermediate
 bridge that cannot perform wavelength conversion, and is described in
 [RFC3473].

Fedyk, et al. Standards Track [Page 12] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

4.4. Protection Paths

 When protection is used for path recovery, it is required to
 associate the working and protection paths into a protection group.
 This is achieved as defined in [RFC4872] and [RFC4873] using the
 ASSOCIATION and PROTECTION objects.

4.5. Service Instance Identification

 The I-SID is used to uniquely identify services within the network.
 Unambiguous identification is achieved by ensuring global uniqueness
 of the I-SIDs within the network or at least between any pair of edge
 bridges.  On IB-BEBs, the Backbone Service Instance Table is used to
 configure the mapping between I-SIDs and ESPs.  This configuration
 can be either manual or semi-automated by signaling described here.
 RSVP-TE Signaling MAY be used to automate I-SID to ESP mapping.  By
 relying on signaling, it is ensured that the same I-SID is assigned
 to the service and mapped to the same ESP.  Note, by signaling the
 I-SID associated to the ESP, one can ensure that IB-BEBs select the
 appropriate CBP port.
 CALL signaling [RFC4974] MAY be used to create an association between
 the Eth-LSP endpoints prior to establishment of the LSP.  The
 CALL_ATTRIBUTES object can be used during CALL signaling, as
 described in [RFC4974], to indicate properties of the CALL.  The
 Service ID TLV, defined below, can be carried in the CALL_ATTRIBUTES
 object to indicate the I-SID to ESP mapping for the Eth-LSP that will
 be set up in association with the CALL.
 Alternatively, the GMPLS RSVP-TE PATH message can carry the I-SID
 association using the Service ID TLV in the LSP_ATTRIBUTES object
 [RFC5420] at the time of Eth-LSP signaling.  Using this mechanism, it
 is possible to create the I-SID association, either when the path is
 set up or at a later time using a PATH refresh.
 A new Service ID TLV is defined for the CALL_ATTRIBUTES and
 LSP_ATTRIBUTES objects.  The type value is 3 when carried in the
 CALL_ATTRIBUTES object and the type value is 2 when carried in the
 LSP_ATTRIBUTES object. The format is depicted below.

Fedyk, et al. Standards Track [Page 13] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

     0                   1                   2                   3
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |             Type              |      Length (variable)        |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                       I-SID Set Object 1                      |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    :                               :                               :
    :                               :                               :
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                       I-SID Set Object n                      |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                         Figure 4: Service ID TLV
  1. I-SID Set Object: is used to define a list or range of I-SIDs.

Multiple I-SID Set Objects can be present. At least one I-SID

      Set Object MUST be present.  In most of the cases, a single
      I-SID Set Object with a single I-SID value is used.  The I-SID
      Set Object is used to define a list or range of I-SIDs.  The
      format of the I-SID Set Object is based on the LABEL_SET Object:
     0                   1                   2                   3
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |    Action     |  Reserved     |        Length                 |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |   Reserved    |            I-SID 1                            |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    :                               :                               :
    :                               :                               :
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |   Reserved    |            I-SID n                            |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                        Figure 5: I-SID Set Object
  1. Action: 8 bits
      The following actions are defined: list (0), range (1).  When a
      range is defined, there are only two I-SIDs that follow the
      beginning I-SID and the end of the range I-SID.  When list is
      defined, a number of I-SIDs may be defined.
  1. Length: 16 bits
      This indicates the length of the I-SID Set object.

Fedyk, et al. Standards Track [Page 14] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

  1. I-SID: 24 bits
      The I-SID value identifies a particular backbone service
      instance.

5. Error Conditions

 The following errors identify Eth-LSP-specific problems.
 In PBB-TE, a set of ESP-VIDs allocated to PBB-TE must be configured.
 Therefore, it is possible in some situations that the configuration
 of a bridge is not the same as other bridges.  If the ESP-VIDs of
 various bridges have some ESP-VIDs in common, it is possible some
 paths may be set up before encountering issues.  This is a management
 issue since all bridges should have the same ESP-VID range.
 Configuration should be consistent.

5.1. ESP-VID-Related Errors

 The network operator administratively selects a set of VLAN
 Identifiers that can be used to set up ESPs.  Consequently, any VID
 outside the allocated range is invalid, and an error MUST be
 generated where the mismatch is discovered.  The Error indication is
 carried in the PathErr message from any intermediate bridge that does
 not support the signaled source VID or optionally the destination
 VID.  The Error MAY be indicated in the ResvErr if the allocation
 error happens on the RESV message.  In this case, a bridge that does
 not support the signaled destination VID MUST signal the error.

5.1.1. Invalid ESP-VID Value in the PBB-TE Ethernet Label

 If a bridge is not configured to use the ESP-VID value, carried in
 the Label object, for PBB-TE ESPs, it MUST immediately generate an
 error: Routing problem (24) / Unacceptable label value (6).  Handling
 of this error is according to [RFC3209].
 Note that an originating bridge can reuse an ESP-VID with a different
 source or destination B-MAC address.  By allocating a number of
 B-MACs and a number of ESP-VIDs, a large number of PBB-TE connections
 may be supported.
 Note, this error may be originated by any bridge along the path.

Fedyk, et al. Standards Track [Page 15] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

5.1.2. Allocated ESP-VID Range is Exhausted

 The destination bridge, after receiving the PATH message, has to
 assign a VID, which, together with its MAC address, will constitute
 the PBB-TE Ethernet Label.  An existing VID may be reused when shared
 forwarding is used or when there are no path conflicts; otherwise,
 the bridge has to allocate a VID.
 Depending on the size of the allocated VLAN range and the number of
 Eth-LSPs terminated on a particular bridge, it is possible that the
 available VIDs are exhausted; hence, no PBB-TE Ethernet Label can be
 allocated.  In this case, the destination bridge SHOULD generate a
 PathErr message with error code: Routing problem (24) and error
 value: MPLS Label allocation failure (9).

5.2. Invalid MAC Address

 IEEE defines a set of reserved MAC addresses from 01-80-C2-00-00-00
 to 01-80-C2-00-00-0F as explained in [IEEE802.1Q] that have special
 meaning, processing, and follow specific forwarding rules.  These
 addresses cannot be used for PBB-TE ESPs.  In the case the PBB-TE
 Ethernet Label refers to such a MAC address, a bridge encountering
 the mismatch MUST immediately generate an error: Routing problem (24)
 / Unacceptable label value (6).  Handling of this error is according
 to [RFC3209].

6. Security Considerations

 This document does not introduce new security issues; the
 considerations in [RFC4872] and [RFC4873] apply.
 A GMPLS-controlled Ethernet PBB-TE system assumes that users and
 devices attached to User-to-Network Interfaces (UNIs) may behave
 maliciously, negligently, or incorrectly.  Intra-provider control
 traffic is trusted not to be malicious.  In general, these
 requirements are no different from the security requirements for
 operating any GMPLS network.  Access to the trusted network will only
 occur through the protocols defined for the UNI or Network-to-Network
 Interface (NNI) or through protected management interfaces.
 When in-band GMPLS signaling is used for the control plane, the
 security of the control plane and the data plane may affect each
 other.  When out-of-band GMPLS signaling is used for the control
 plane, the data-plane security is decoupled from the control plane;
 therefore, the security of the data plane has less impact on overall
 security.

Fedyk, et al. Standards Track [Page 16] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 Where GMPLS is applied to the control of VLAN only, the commonly
 known techniques for mitigation of Ethernet denial-of-service (DoS)
 attacks may be required on UNI ports.  PBB-TE has been designed to
 interwork with legacy VLANs and the VLANs provide isolation from
 Ethernet legacy control planes.
 Where control-plane communications are point-to-point over links that
 employ 802.1AE Media Access Control Security [MACSEC], it may
 reasonably be determined that no further security measures are used.
 In other cases, it is appropriate to use control-plane security where
 it is deemed necessary to secure the signaling messages.  GMPLS
 signaling security measures are described in [RFC3471] and [RFC3473],
 and they inherit security techniques applicable to RSVP-TE, as
 described in [RFC3209] and [RFC2205].  For a fuller overview of GMPLS
 security techniques, see [RFC5920].

7. IANA Considerations

 A new Switching Type, "802_1 PBB-TE" (40), has been assigned in the
 Switching Types registry of the GMPLS Signaling Parameters registry.
 The Service ID TLV has been assigned in the Attributes TLV Space in
 the RSVP-TE Parameters registry.  It is carried in the LSP_ATTRIBUTES
 object (class = 197, C-Type = 1) [RFC5420].  This new type has been
 registered as follows:
    Type: 2
    Name: Service ID TLV
    Allowed on LSP_ATTRIBUTES: Yes
    Allowed on LSP_REQUIRED_ATTRIBUTES: No
 The Service ID TLV has been assigned value 3 in the Call Attributes
 TLV registry in the RSVP Parameters registry.  It is carried in the
 CALL_ATTRIBUTES object (class = 202, C-Type = 1) defined by
 [RFC6001].

8. References

8.1. Normative References

 [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
            Requirement Levels", BCP 14, RFC 2119, March 1997.
 [RFC2205]  Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
            Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
            Functional Specification", RFC 2205, September 1997.

Fedyk, et al. Standards Track [Page 17] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

 [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
            and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
            Tunnels", RFC 3209, December 2001.
 [RFC3471]  Berger, L., Ed., "Generalized Multi-Protocol Label
            Swicthing (GMPLS) Signaling Functional Description", RFC
            3471, January 2003.
 [RFC3473]  Berger, L., Ed., "Generalized Multi-Protocol Label
            Switching (GMPLS) Signaling Resource ReserVation Protocol-
            Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
            January 2003.
 [RFC3945]  Mannie, E., Ed., "Generalized Multi-Protocol Label
            Switching (GMPLS) Architecture", RFC 3945, October 2004.
 [RFC4872]  Lang, J., Ed., Rekhter, Y., Ed., and D. Papadimitriou,
            Ed., "RSVP-TE Extensions in Support of End-to-End
            Generalized Multi-Protocol Label Switching (GMPLS)
            Recovery", RFC 4872, May 2007.
 [RFC4873]  Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel,
            "GMPLS Segment Recovery", RFC 4873, May 2007.
 [RFC4974]  Papadimitriou, D. and A. Farrel, "Generalized MPLS (GMPLS)
            RSVP-TE Signaling Extensions in Support of Calls", RFC
            4974, August 2007.
 [RFC5420]  Farrel, A., Ed., Papadimitriou, D., Vasseur, JP., and A.
            Ayyangarps, "Encoding of Attributes for MPLS LSP
            Establishment Using Resource Reservation Protocol Traffic
            Engineering (RSVP-TE)", RFC 5420, February 2009.
 [RFC6001]  Papadimitriou, D., Vigoureux, M., Shiomoto, K., Brungard,
            D., and JL. Le Roux, "Generalized MPLS (GMPLS) Protocol
            Extensions for Multi-Layer and Multi-Region Networks
            (MLN/MRN)", RFC 6001, October 2010.

Fedyk, et al. Standards Track [Page 18] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

8.2. Informative References

 [IEEE802.1ah]
            "IEEE Standard for Local and Metropolitan Area Networks -
            Virtual Bridged Local Area Networks - Amendment 6:
            Provider Backbone Bridges", (2008)
 [IEEE802.1Q]
            "IEEE Standard for Local and Metropolitan Area Networks -
            Virtual Bridged Local Area Networks", IEEE Std
            802.1Q-2005, May 19, 2006.
 [IEEE802.1Qay]
            "IEEE Standard for Local and Metropolitan Area Networks -
            Virtual Bridged Local Area Networks - Amendment : Provider
            Backbone Bridges Traffic Engineering", 2009.
 [MACSEC]   "IEEE Standard for Local and metropolitan area networks
            Media Access Control (MAC) Security", IEEE 802.1AE-2006,
            August 18, 2006.
 [RFC4875]  Aggarwal, R., Ed., Papadimitriou, D., Ed., and S.
            Yasukawa, Ed., "Extensions to Resource Reservation
            Protocol - Traffic Engineering (RSVP-TE) for Point-to-
            Multipoint TE Label Switched Paths (LSPs)", RFC 4875, May
            2007.
 [RFC4655]  Farrel, A., Vasseur, J.-P., and J. Ash, "A Path
            Computation Element (PCE)-Based Architecture", RFC 4655,
            August 2006.
 [RFC5828]  Fedyk, D., Berger, L., and L. Andersson, "Generalized
            Multiprotocol Label Switching (GMPLS) Ethernet Label
            Switching Architecture and Framework", RFC 5828, March
            2010.
 [RFC5920]   Fang, L., Ed., "Security Framework for MPLS and GMPLS
            Networks", RFC 5920, July 2010.

9. Acknowledgments

 The authors would like to thank Dinesh Mohan, Nigel Bragg, Stephen
 Shew, Dave Martin and Sandra Ballarte for their contributions to this
 document.  The authors thank Deborah Brungard and Adrian Farrel for
 their review and suggestions to this document.

Fedyk, et al. Standards Track [Page 19] RFC 6060 GMPLS Control of Ethernet PBB-TE March 2011

Authors' Addresses

 Don Fedyk
 Alcatel-Lucent
 Groton, MA  01450
 Phone: +1-978-467-5645
 EMail: donald.fedyk@alcatel-lucent.com
 Himanshu Shah
 Ciena
 1741 Technology Dr, #400
 San Jose, CA  95110
 Phone: 508-435-0448
 EMail: hshah@ciena.com
 Nabil Bitar
 Verizon
 40 Sylvan Rd.
 Waltham, MA  02451
 EMail: nabil.n.bitar@verizon.com
 Attila Takacs
 Ericsson
 1. Laborc u.
 Budapest, HUNGARY 1037
 EMail: attila.takacs@ericsson.com

Fedyk, et al. Standards Track [Page 20]

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