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Generalized Multiprotocol Label Switching (GMPLS) Control of Ethernet Provider Backbone Traffic Engineering (PBB-TE)

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 6060.
Authors Dr. Nabil N. Bitar , Himanshu C. Shah , Attila Takacs , Don Fedyk
Last updated 2015-10-14 (Latest revision 2010-09-28)
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IESG IESG state Became RFC 6060 (Proposed Standard)
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Internet Draft                                 Don Fedyk, Alcatel-Lucent
Category: Standards Track                Himanshu Shah, Force10 Networks
Expiration Date: March 28, 2011                     Nabil Bitar, Verizon
                                                 Attila Takacs, Ericsson

                                                      September 28, 2010

      Generalized Multiprotocol Label Switching (GMPLS) control of
        Ethernet Provider Backbone Traffic Engineering (PBB-TE)


Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

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Copyright and License Notice

   Copyright (c) 2010 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
   ( in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with respect
   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 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.

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Table of Contents

    1      Introduction  ...........................................   4
    1.1    Co-authors  .............................................   4
    2      Terminology  ............................................   5
    2.1    PBB-TE and GMPLS Terminology  ...........................   5
    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  ....................................  11
    4.1    P2P Ethernet LSPs   .....................................  11
    4.1.1  P2P Path Maintenance  ...................................  12
    4.2    P2MP Ethernet-LSPs  .....................................  12
    4.3    PBB-TE Ethernet Label  ..................................  13
    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  ....  16
    5.1.2   Allocated ESP-VID range is exhausted  ..................  16
    5.2    Invalid MAC Address  ....................................  16
    6      Security Considerations  ................................  17
    7      IANA Considerations  ....................................  17
    8      References  .............................................  18
    8.1    Normative References  ...................................  18
    8.2    Informative References  .................................  19
    9      Acknowledgments  ........................................  19
   10      Author's Address  .......................................  20

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Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL
   in this document are to be interpreted as described in [RFC2119].

1. Introduction

   The IEEE 802.1 Provider Backbone Bridge Traffic Engineering (PBB-TE)
   [IEEE 802.1Qay] standard supports the establishment of explicitly
   routed traffic engineered paths within Provider Backbone Bridged
   (PBB) networks. PBB-TE allows disabling of:
     - the Spanning Tree Protocol
     - unknown destination address forwarding
     - 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 Layer 2 Switching capable networks
   (L2SC).  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 with the
   GMPLS Ethernet Label Switching Architecture and Framework [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:

      Don Fedyk (Alcatel-Lucent)
      David Allan  (Ericsson)
      Himanshu Shah (Force10 Networks)
      Nabil Bitar (Verizon)
      Attila Takacs (Ericsson)
      Diego Caviglia (Ericsson)
      Alan McGuire (BT)
      Nurit Sprecher (Nokia Siemens Networks)
      Lou Berger (LabN)

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2. Terminology

   In addition to well understood GMPLS terms, this memo uses
   terminology from IEEE 802.1  [IEEE 802.1ah] [IEEE 802.1Qay]:

     - BCB                 Backbone Core Bridge
     - BEB                 Backbone Edge Bridge
     - B-MAC               Backbone MAC
     - B-VID               Backbone VLAN ID
     - B-VLAN              Backbone VLAN
     - CBP                 Customer Backbone Port
     - CCM                 Continuity Check Message
     - CNP                 Customer Network Port
     - C-MAC               Customer MAC
     - C-VID               Customer VLAN ID
     - C-VLAN              Customer VLAN
     - ESP                 Ethernet Switched Path
     - ESP-MAC SA          ESP Source MAC Address
     - ESP-MAC DA          ESP Destination MAC Address
     - ESP-VID             ESP VLAN ID
     - Eth-LSP             Ethernet Label Switched Path
     - IB-BEB              A BEB comprising of both I and B components
     - I-SID               Ethernet Service Instance Identifier
     - TAG                 An Ethernet Header Field with Type and Values
     - MAC                 Media Access Control
     - PBB                 Provider Backbone Bridges
     - PBB-TE              Provider Backbone Bridges Traffic Engineering
     - PIP                 Provider Instance Port
     - PNP                 Provider Network Port
     - PS                  Protection Switching
     - P2P                 Point to Point
     - P2MP                Point to Multipoint
     - SVL                 Shared VLAN Learning
     - TESI                Traffic Engineering Service Instance
     - VID                 VLAN ID
     - VIP                 Virtual Instance Port
     - VLAN                Virtual LAN

2.1. PBB-TE and GMPLS Terminology

   The PBB-TE specification [IEEE 802.1Qay] 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.

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     - Ethernet Switched Path (ESP):
       A provisioned traffic engineered unidirectional connectivity path
       between two or more Customer Backbone Ports (CBPs) which 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.

     - 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

     - 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
     - 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 ESP are forming a bidirectional service. The PBB-
       TE standard [IEEE 802.1Qay] 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 co-
       routed.  Support for a point-to-point TE services which 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.

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 set-up, 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

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   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 which are connected via an internal
   LAN. These internal ports are the Provider Instance Ports (PIPs) and
   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 it 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

   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
   there are more than one suitable CBPs, and no I-SID information is

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   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 CBP is configured with the I-SID
   and MUST assign that CBP to the ESP.

                      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                    |

                            ^-----------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

             Figure 2 Ethernet/GMPLS Addressing & Label Space

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   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.

   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

   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 setup, 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

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   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
   directions.  In this scenario the originating bridge uses the
   LABEL_SET and UPSTREAM_LABEL objects to indicate 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 MAC ESP-VID/ESP-MAC DA/ESP- MAC SA
   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 (i.e., Eth-LSP + priority) basis 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

   The concept of bandwidth management still applies equally well with
   shared forwarding.

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4. Specific Procedures

4.1. P2P Ethernet LSPs

   Note, 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
   the following 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.     To initiate a bidirectional Eth-LSP, the initiator
   of the PATH message MUST use the procedures outlined in [RFC3473]
   with the following specifics:

   1) MUST set the LSP encoding type to Ethernet (2) [RFC3471].

   2) MUST set the LSP switching type to "802_1 PBB-TE" suggested value

   3) SHOULD set the GPID to Ethernet (33) [RFC3471].

   4) MUST set the UPSTREAM_LABEL to the ESP-VID1/ESP-MAC1 tuple where
      ESP-VID1 is administered locally for the local MAC address: MAC1

   5) SHOULD set the LABEL_SET or SUGGESTED_LABEL if it chooses to
      influence the choice of ESP-VID/ESP-MAC DA.

   6) 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 are 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

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   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 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 switching operations such
   that modification is only ever performed on the protection path. PS
   is a native capability of PBB-TE [IEEE 802.1Qay] that can operate
   when two paths are set up between two common end points.

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

   Complete procedures for signaling bidirectional P2MP are out of scope
   for this document.

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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, while 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].

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.

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   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 format is depicted below.

       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 (TBA)          |      Length (variable)        |
      |                          I-SID Set 1                          |
      :                               :                               :
      :                               :                               :
      |                            I-SID Set n                        |
                          Figure 4 Service ID TLV

     - Flags: are used to control properties of service configuration.
       This document does not define flags.

     - I-SID Set TLV(Type 1): is used to define a list or range of I-
       SIDs. Multiple I-SID Set TLVs can be present. At least one I-SID
       Set TLV MUST be present. In most of the cases a single I-SID Set
       with a single I-SID value is used. The I-SID Set TLV is used to
       define a list or range of I-SIDs. The format of the I-SID Set TLV
       is based on the LABEL_SET Object:

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     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                   |
    |   Reserved    |          I-SID 1                              |
    :                               :                               :
    :                               :                               :
    |   Reserved    |          I-SID n                           |
                         Figure 5 I-SID Set TLV
     - 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.
     - I-SID: 24 bits

       The I-SID value identifies a particular backbone service

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 setup 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.

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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.

5.1.2.  Allocated ESP-VID range is exhausted

   The destination bridge after receiving the PATH message has to
   allocate a VID, which together with its MAC address will constitute
   the PBB-TE Ethernet Label. 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 and
   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

5.2. Invalid MAC Address

   IEEE defines a set of reserved MAC addresses Table 8-1 [IEEE 802.1Q]
   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].

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6. Security Considerations

   This document does not introduces new security issues; the
   considerations in [RFC4872] and [RFC4873] apply.

   GMPLS controlled Ethernet PBB-TE system assumes that users and
   devices attached to UNIs may behave maliciously, negligently, or
   incorrectly.  Intra-provider control traffic is trusted to not 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 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 and
   therefore the security of the data plane has less impact on overall

   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.  PBB-TE has been designed to interwork with
   legacy VLANs and the VLANs provide isolation from Ethernet legacy
   control planes.

   For a more comprehensive discussion on GMPLS security please see the
   Security Framework for MPLS and GMPLS Networks[RFC5920].
   Cryptography can be used to protect against many attacks described in
   [RFC5920].  One option for protecting "transport" Ethernet is the use
   of 802.1AE Media Access Control Security, [MACSEC] which provides
   encryption and authentication."

7. IANA Considerations

     - Assign a new Switching Type: "802_1 PBB-TE" (suggested value 40)
       in the GMPLS Signaling Parameters / Switching Types registry.

     - Assign a new globally defined error value: "PBB-TE Ethernet Label
       VID allocation failure" (suggested value: 35?)  under the
       "Routing problem" (24) error code in the RSVP Parameters / Error
       Codes and Globally-Defined Error Value Sub-Codes registry.

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     - Assign a new type from the Attributes TLV Space in the RSVP-TE
       Parameters registry (suggested value 2) for the Service ID TLV
       that is carried in the LSP_ATTRIBUTES Object (class = 197, C-Type
       = 1) [RFC5420].

     - Assign a new type (suggested value 2) for the Service ID TLV that
       is carried in the CALL_ATTRIBUTES Object (class = 202, C-Type =
       1) Registry class defined by [MLN-EXT].

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.

   [RFC3471] Berger, L., "Generalized Multi-Protocol Label
      Switching (GMPLS) Signaling Functional Description" IETF
      RFC 3471, January 2003.

   [RFC3473] Berger, L., "Generalized Multi-Protocol Label
      Switching (GMPLS) Signaling Resource ReserVation Protocol-Traffic
      Engineering (RSVP-TE) Extensions", IETF RFC 3473, January 2003.

   [RFC3945] Mannie, E., "Generalized Multi-Protocol Label
      Switching (GMPLS) Architecture", IETF RFC 3945, October 2004.

   [MLN-EXT] Papadimitriou, D. et al,  "Generalized Multi-Protocol
      Label Switching (GMPLS) Protocol Extensions for Multi-Layer
      and Multi-Region Networks (MLN/MRN)",
      draft-ietf-ccamp-gmpls-mln-extensions, work in progress.

   [RFC5420] Farrel, A. Ed., "Encoding of Attributes for MPLS LSP
      Establishment Using Resource Reservation Protocol Traffic
      Engineering (RSVP-TE), IETF RFC 5420, February 2009.

   [RFC4872] Lang, J., "RSVP-TE Extensions in support of
      End-to-End Generalized Multi-Protocol Label Switching
      (GMPLS)-based Recovery", RFC 4871, May 2007.

   [RFC4873] Berger, L.,"MPLS Segment Recovery", RFC 4873, May

   [RFC3209] Awduche, D., "RSVP-TE: Extensions to RSVP for LSP
      Tunnels, IETF RFC 3209, December 2001.

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   [RFC4974] Papadimitriou, D. and Farrel, A. "Generalized MPLS (GMPLS)
      RSVP-TE Signaling Extensions in Support of Calls", August 2007.

8.2. Informative References

   [RFC5828] Fedyk, D. Berger, L., Andersson L., "GMPLS Ethernet Label
      Switching Architecture and Framework", RFC 5828, March 2010.

   [IEEE 802.1Qay] "IEEE Standard for Local and Metropolitan Area
      Networks - Virtual Bridged Local Area Networks
      - Amendment : Provider Backbone Bridges Traffic Engineering

   [IEEE 802.1Q] "IEEE Standard for Local and Metropolitan Area
      Networks - Virtual Bridged Local Area Networks",
      IEEE Std 802.1Q-2005, May 19, 2006.

   [IEEE 802.1ah] "IEEE Standard for Local and Metropolitan Area
      Networks - Virtual Bridged Local Area Networks
      - Amendment 6: Provider Backbone Bridges", (2008)

   [RFC4875] Aggarwal, R. Ed., "Extensions to RSVP-TE for Point to
      Multipoint TE LSPs", IETF RFC 4875, May 2007

   [RFC4655] Farrel, A., "Path Computation Element (PCE)
      Architecture", IETF RFC 4655, August 2006

   [RFC5920] Fang, L.,"Security Framework for MPLS and GMPLS
      Networks", RFC 5920, July 2010.

   [MACSEC]  "IEEE Standard for Local and metropolitan area networks
      Media Access Control (MAC) Security IEEE 802.1AE-2006",
      August 18, 2006.

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.

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10. Author's Address

   Don Fedyk
   Groton, MA, 01450
   Phone: +1-978-467-5645

   David Allan

   Himanshu Shah
   Force10 Networks
   30 Nagog Park,
   Acton, MA 01720

   Nabil Bitar
   40 Sylvan Rd.,
   Waltham, MA 02451

   Attila Takacs
   1. Laborc u.
   Budapest, HUNGARY 1037

   Diego Caviglia
   Via Negrone 1/A
   Genoa, Italy 16153

   Alan McGuire
   BT Group PLC
   OP6 Polaris House,
   Adastral Park, Martlesham Heath,
   Ipswich, Suffolk, IP5 3RE, UK

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   Nurit Sprecher
   Nokia Siemens Networks,
   GmbH & Co. KG
   COO RTP IE Fixed
   3 Hanagar St. Neve Ne'eman B,
   45241 Hod Hasharon, Israel

   Lou Berger
   LabN Consulting, L.L.C.
   Phone: +1-301-468-9228

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