[Docs] [txt|pdf|xml|html] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-margaria-pce-gmpls-pcep-extensions) 00 01 02 03 04 05 06 07 08 09 10 11 12

Network Working Group                                   C. Margaria, Ed.
Internet-Draft                                                   Juniper
Intended status: Standards Track                O. Gonzalez de Dios, Ed.
Expires: March 31, 2019            Telefonica Investigacion y Desarrollo
                                                           F. Zhang, Ed.
                                                     Huawei Technologies
                                                      September 27, 2018


                       PCEP extensions for GMPLS
                draft-ietf-pce-gmpls-pcep-extensions-12

Abstract

   This memo provides extensions to the Path Computation Element
   communication Protocol (PCEP) for the support of GMPLS control plane.

Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on March 31, 2019.

Copyright Notice

   Copyright (c) 2018 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
   (https://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
   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.



Margaria, et al.         Expires March 31, 2019                 [Page 1]


Internet-Draft             PCEP Ext for GMPLS             September 2018


Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Contributing Authors  . . . . . . . . . . . . . . . . . .   3
     1.2.  PCEP Requirements for GMPLS . . . . . . . . . . . . . . .   3
     1.3.  Current GMPLS Support and Limitation of Base PCEP Objects   4
     1.4.  Requirements Language . . . . . . . . . . . . . . . . . .   5
   2.  PCEP Objects and Extensions . . . . . . . . . . . . . . . . .   6
     2.1.  GMPLS Capability Advertisement  . . . . . . . . . . . . .   6
       2.1.1.  GMPLS Computation TLV in the Existing PCE Discovery
               Protocol  . . . . . . . . . . . . . . . . . . . . . .   6
       2.1.2.  OPEN Object Extension GMPLS-CAPABILITY TLV  . . . . .   6
     2.2.  RP Object Extension . . . . . . . . . . . . . . . . . . .   7
     2.3.  BANDWIDTH Object Extensions . . . . . . . . . . . . . . .   7
     2.4.  LOAD-BALANCING Object Extensions  . . . . . . . . . . . .  10
     2.5.  END-POINTS Object Extensions  . . . . . . . . . . . . . .  11
       2.5.1.  Generalized Endpoint Object Type  . . . . . . . . . .  12
       2.5.2.  END-POINTS TLV Extensions . . . . . . . . . . . . . .  15
     2.6.  IRO Extension . . . . . . . . . . . . . . . . . . . . . .  18
     2.7.  XRO Extension . . . . . . . . . . . . . . . . . . . . . .  18
     2.8.  LSPA Extensions . . . . . . . . . . . . . . . . . . . . .  20
     2.9.  NO-PATH Object Extension  . . . . . . . . . . . . . . . .  20
       2.9.1.  Extensions to NO-PATH-VECTOR TLV  . . . . . . . . . .  21
   3.  Additional Error-Types and Error-Values Defined . . . . . . .  21
   4.  Manageability Considerations  . . . . . . . . . . . . . . . .  23
     4.1.  Control of Function through Configuration and Policy  . .  23
     4.2.  Information and Data Models . . . . . . . . . . . . . . .  23
     4.3.  Liveness Detection and Monitoring . . . . . . . . . . . .  23
     4.4.  Verifying Correct Operation . . . . . . . . . . . . . . .  24
     4.5.  Requirements on Other Protocols and Functional Components  24
     4.6.  Impact on Network Operation . . . . . . . . . . . . . . .  24
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  24
     5.1.  PCEP Objects  . . . . . . . . . . . . . . . . . . . . . .  24
     5.2.  END-POINTS Object, Object Type Generalized Endpoint . . .  25
     5.3.  New PCEP TLVs . . . . . . . . . . . . . . . . . . . . . .  26
     5.4.  RP Object Flag Field  . . . . . . . . . . . . . . . . . .  26
     5.5.  New PCEP Error Codes  . . . . . . . . . . . . . . . . . .  27
     5.6.  New NO-PATH-VECTOR TLV Fields . . . . . . . . . . . . . .  28
     5.7.  New Subobject for the Include Route Object  . . . . . . .  28
     5.8.  New Subobject for the Exclude Route Object  . . . . . . .  28
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  29
   7.  Contributing Authors  . . . . . . . . . . . . . . . . . . . .  30
   8.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  31
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  32
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  32
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  35
   Appendix A.  LOAD-BALANCING Usage for SDH Virtual Concatenation .  35
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  36



Margaria, et al.         Expires March 31, 2019                 [Page 2]


Internet-Draft             PCEP Ext for GMPLS             September 2018


1.  Introduction

   Although [RFC4655] defines the PCE architecture and framework for
   both MPLS and GMPLS networks, most preexisting PCEP RFCs [RFC5440],
   [RFC5521], [RFC5541], [RFC5520] are focused on MPLS networks, and do
   not cover the wide range of GMPLS networks.  This document
   complements these RFCs by addressing the extensions required for
   GMPLS applications and routing requests, for example for OTN and WSON
   networks.

   The functional requirements to be considered by the PCEP extensions
   to support those application are described in [RFC7025] and
   [RFC7449].

1.1.  Contributing Authors

   Elie Sfeir, Franz Rambach (Nokia Siemens Networks) Francisco Javier
   Jimenez Chico (Telefonica Investigacion y Desarrollo) Suresh BR,
   Young Lee, SenthilKumar S, Jun Sun (Huawei Technologies), Ramon
   Casellas (CTTC)

1.2.  PCEP Requirements for GMPLS

   The document [RFC7025] describes the set of PCEP requirements to
   support GMPLS TE-LSPs.  When a PCC requests a PCE to perform a path
   computation (by means of a PCReq message), the PCC should be able to
   indicate the following additional information:

   o  Which data flow is switched by the LSP: a combination of Switching
      type (for instance L2SC or TDM), LSP Encoding type (e.g.,
      Ethernet, SONET/SDH) and sometimes the Signal Type (e.g. in case
      of TDM/LSC switching capability)

   o  Data flow specific traffic parameters, which are technology
      specific.  For instance, in SDH/SONET and G.709 OTN networks the
      Concatenation Type and the Concatenation Number have an influence
      on the switched data and on which link it can be supported

   o  Support for asymmetric bandwidth requests.

   o  Support for unnumbered interface identifiers, as defined in
      [RFC3477]

   o  Label information and technology specific label(s) such as
      wavelength labels as defined in [RFC6205].  A PCC should also be
      able to specify a Label restriction similar to the one supported
      by RSVP-TE (Resource Reservation Protocol - Traffic Engineering).




Margaria, et al.         Expires March 31, 2019                 [Page 3]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   o  Ability to indicate the requested granularity for the path ERO:
      node, link or label.  This is to allow the use of the explicit
      label control feature of RSVP-TE.

   We describe in this document a set of PCEP protocol extensions,
   including new object types, TLVs, encodings, error codes and
   procedures, in order to fulfill the aforementioned requirements.

1.3.  Current GMPLS Support and Limitation of Base PCEP Objects

   PCEP as of [RFC5440], [RFC5521] and [RFC8282], supports the following
   objects, included in requests and responses related to the described
   requirements.

   From [RFC5440]:

   o  END-POINTS: only numbered endpoints are considered.  The context
      specifies whether they are node identifiers or numbered
      interfaces.

   o  BANDWIDTH: the data rate is encoded in the bandwidth object (as
      IEEE 32 bit float).  [RFC5440] does not include the ability to
      convey an encoding proper to all GMPLS-controlled networks.

   o  ERO: Unnumbered IDs are supported.

   o  LSPA: LSP attributes (setup and holding priorities)

   From [RFC5521]:

   o  XRO object:

      *  This object allows excluding (strict or not) resources, and
         includes the requested diversity (node, link or SRLG).

      *  When the F bit is set, the request indicates that the existing
         path has failed and the resources present in the RRO can be
         reused.

   From [RFC8282]:

   o  INTER-LAYER: indicates whether inter-layer computation is allowed

   o  SWITCH-LAYER: indicates which layer(s) should be considered, can
      be used to represent the RSVP-TE generalized label request

   o  REQ-ADAP-CAP: indicates the adaptation capabilities requested, can
      also be used for the endpoints in case of mono-layer computation



Margaria, et al.         Expires March 31, 2019                 [Page 4]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   The shortcomings of the base PCEP object are:

      The BANDWIDTH and LOAD-BALANCING objects do not describe the
      details of the traffic request (for example NVC, multiplier) in
      the context of GMPLS networks, for instance TDM or OTN networks.

      The END-POINTS object does not allow specifying an unnumbered
      interface, nor potential label restrictions on the interface.
      Those parameters are of interest in case of switching constraints.

      The Inclue/eXclude Route Objects (IRO/XRO) do not allow the
      inclusion/exclusion of labels.

   Base attributes do not allow expressing the requested link protection
   level and/or the end-to-end protection attributes.

   The covered PCEP extensions are:

      Two new object types are introduced for the BANDWIDTH
      object(Generalized bandwidth, Generalized bandwidth of existing
      TE-LSP for which a reoptimization is requested for which a
      reoptimization is requested).

      A new object type is introduced for the LOAD-BALANCING object
      (Generalized Load Balancing).

      A new object type is introduced for the END-POINTS object
      (Generalized Endpoint).

      A new TLV is added to the OPEN message for capability negotiation.

      A new TLV is added to the LSPA object.

      A new TLV type for label is allowed in IRO and XRO objects.

      In order to indicate the used routing granularity in the response,
      a new flag in the RP object is added.

1.4.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].








Margaria, et al.         Expires March 31, 2019                 [Page 5]


Internet-Draft             PCEP Ext for GMPLS             September 2018


2.  PCEP Objects and Extensions

   This section describes the necessary PCEP objects and extensions.
   The PCReq and PCRep messages are defined in [RFC5440].  This document
   does not change the existing grammars

2.1.  GMPLS Capability Advertisement

2.1.1.  GMPLS Computation TLV in the Existing PCE Discovery Protocol

   IGP-based PCE Discovery (PCED) is defined in [RFC5088] and [RFC5089]
   for the OSPF and IS-IS protocols.  Those documents have defined bit 0
   in PCE-CAP-FLAGS Sub-TLV of the PCED TLV as "Path computation with
   GMPLS link constraints".  This capability can be used to detect
   GMPLS-capable PCEs.

2.1.2.  OPEN Object Extension GMPLS-CAPABILITY TLV

   In addition to the IGP advertisement, a PCEP speaker SHOULD be able
   to discover the other peer GMPLS capabilities during the Open message
   exchange.  This capability is also useful to avoid misconfigurations.
   This document defines a new OPTIONAL GMPLS-CAPABILITY TLV for use in
   the OPEN object to negotiate the GMPLS capability.  The inclusion of
   this TLV in the OPEN message indicates that the PCC/PCE support the
   PCEP extensions defined in the document.  A PCE that is able to
   support the GMPLS extensions defined in this document SHOULD include
   the GMPLS-CAPABILITY TLV on the OPEN message.  If the PCE does not
   include the GMPLS-CAPABILITY TLV in the OPEN message and PCC does
   include the TLV, it is RECOMMENDED that the PCC indicates a mismatch
   of capabilities.  Moreover, in case that the PCC does not receive the
   GMPLS-CAPABILITY TLV it is RECOMMENDED that the PCC does not make use
   of the objects and TLVs defined in this document.

   IANA has allocated value TBA-1 from the "PCEP TLV Type Indicators"
   sub-registry, as documented in Section 5.3 ("New PCEP TLVs").  The
   description is "GMPLS-CAPABILITY".  Its format is shown in the
   following figure.

     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=14         |           Length              |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                             Flags                             |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   No Flags are defined in this document, they are reserved for future
   use.



Margaria, et al.         Expires March 31, 2019                 [Page 6]


Internet-Draft             PCEP Ext for GMPLS             September 2018


2.2.  RP Object Extension

   Explicit label control (ELC) is a procedure supported by RSVP-TE,
   where the outgoing label(s) is(are) encoded in the ERO.  As a
   consequence, the PCE can provide such label(s) directly in the path
   ERO.  Depending on policies or switching layer, it can be necessary
   for the PCC to use explicit label control or expect explicit link,
   thus it need to indicate in the PCReq which granularity it is
   expecting in the ERO.  This corresponds to requirement 12 of
   [RFC7025] The possible granularities can be node, link or label.  The
   granularities are inter-dependent, in the sense that link granularity
   implies the presence of node information in the ERO; similarly, a
   label granularity implies that the ERO contains node, link and label
   information.

   A new 2-bit routing granularity (RG) flag (Bits TBA-13) is defined in
   the RP object.  The values are defined as follows

                                0: reserved
                                1: node
                                2: link
                                3: label

                             Table 1: RG flag

   The flag in the RP object indicates the requested route granularity.
   The PCE SHOULD follow this granularity and MAY return a NO-PATH if
   the requested granularity cannot be provided.  The PCE MAY return any
   granularity on the route based on its policy.  The PCC can decide if
   the ERO is acceptable based on its content.

   If a PCE honored the requested routing granularity for a request, it
   MUST indicate the selected routing granularity in the RP object
   included in the response.  Otherwise, the PCE MUST use the reserved
   RG to leave the check of the ERO to the PCC.  The RG flag is
   backward-compatible with [RFC5440]: the value sent by an
   implementation (PCC or PCE) not supporting it will indicate a
   reserved value.

2.3.  BANDWIDTH Object Extensions

   From [RFC5440] the object carrying the requested size for the TE-LSP
   is the BANDWIDTH object.  The object types 1 and 2 defined in
   [RFC5440] do not describe enough information to describe the TE-LSP
   bandwidth in GMPLS networks.  The BANDWIDTH object encoding has to be
   extended to allow to express the bandwidth as described in [RFC7025].
   RSVP-TE extensions for GMPLS provide a set of encoding allowing such
   representation in an unambiguous way, this is encoded in the RSVP-TE



Margaria, et al.         Expires March 31, 2019                 [Page 7]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   TSpec and FlowSpec objects.  This document extends the BANDWIDTH
   object with new object types reusing the RSVP-TE encoding.

   The following possibilities are supported by the extended encoding:

   o  Asymmetric bandwidth (different bandwidth in forward and reverse
      direction), as described in [RFC6387]

   o  GMPLS (SDH/SONET, G.709, ATM, MEF etc) parameters.

   This correspond to requirement 3, 4, 5 and 11 of [RFC7025] section
   3.1.

   This document defines two Object Types for the BANDWIDTH object:

   TBA-2  Generalized bandwidth

   TBA-3  Generalized bandwidth of an existing TE-LSP for which a
      reoptimization is requested

   The definitions below apply for Object Type TBA-2 and TBA-3.  The
   body is as follows:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Bandwidth Spec Length      | Rev. Bandwidth Spec Length    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Bw Spec Type  |   Reserved                                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~                     Generalized Bandwidth                     ~
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~          Optional:  Reverse Generalized Bandwidth             ~
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~                       Optional TLVs                           ~
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The BANDWIDTH object type TBA-2 and TBA-3 have a variable length.
   The 16-bit Bandwidth Spec Length field indicates the length of the
   Generalized Bandwidth field.  The Bandwidth Spec Length MUST be
   strictly greater than 0.  The 16-bit Reverse Bandwidth Spec Length




Margaria, et al.         Expires March 31, 2019                 [Page 8]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   field indicates the length of the Reverse Generalized Bandwidth
   field.  The Reverse Bandwidth Spec Length MAY be equal to 0.

   The Bw Spec Type field determines which type of bandwidth is
   represented by the object.

   The Bw Spec Type correspond to the RSVP-TE SENDER_TSPEC (Object Class
   12) C-Types

   The encoding of the fields Generalized Bandwidth and Reverse
   Generalized Bandwidth is the same as the Traffic Parameters carried
   in RSVP-TE, it can be found in the following references.

                      Object Type Name      Reference

                      2           Intserv   [RFC2210]
                      4           SONET/SDH [RFC4606]
                      5           G.709     [RFC4328]
                      6           Ethernet  [RFC6003]
                      7           OTN-TDM   [RFC7139]
                      8           SSON      [RFC7792]

     Table 2: Generalized Bandwidth and Reverse Generalized Bandwidth
                              field encoding

   When a PCC requests a bi-directional path with symmetric bandwidth,
   it SHOULD only specify the Generalized Bandwidth field, and set the
   Reverse Bandwidth Spec Length to 0.  When a PCC needs to request a
   bi-directional path with asymmetric bandwidth, it SHOULD specify the
   different bandwidth in the forward and reverse directions with a
   Generalized Bandwidth and Reverse Generalized Bandwidth fields.

   The procedure described in [RFC5440] for the PCRep is unchanged: a
   PCE MAY include the BANDWIDTH objects in the response to indicate the
   BANDWIDTH of the path.

   As specified in [RFC5440] in the case of the reoptimization of a TE-
   LSP, the bandwidth of the existing TE-LSP MUST also be included in
   addition to the requested bandwidth if and only if the two values
   differ.  The Object Type TBA-3 MAY be used instead of object type 2
   to indicate the existing TE-LSP bandwidth.  A PCC that requested a
   path with a BANDWIDTH object of object type 1 SHOULD use object type
   2 to represent the existing TE-LSP BANDWIDTH.

   OPTIONAL TLVs MAY be included within the object body to specify more
   specific bandwidth requirements.  No TLVs for the Object Type TBA-2
   and TBA-3 are defined by this document.




Margaria, et al.         Expires March 31, 2019                 [Page 9]


Internet-Draft             PCEP Ext for GMPLS             September 2018


2.4.  LOAD-BALANCING Object Extensions

   The LOAD-BALANCING object [RFC5440] is used to request a set of
   maximum Max-LSP TE-LSP having in total the bandwidth specified in
   BANDWIDTH, each TE-LSP having a minimum of bandwidth.  The LOAD-
   BALANCING follows the bandwidth encoding of the BANDWIDTH object, and
   thus the existing definition from [RFC5440] does not describe enough
   details for the bandwidth specification expected by GMPLS.

   Similarly to the BANDWIDTH object, a new object type is defined to
   allow a PCC to represent the bandwidth types supported by GMPLS
   networks.

   This document defines the Generalized Load Balancing object type
   TBA-4 for the LOAD-BALANCING object.  The Generalized Load Balancing
   object type has a variable length.

   The format of the Generalized Load Balancing object type is as
   follows:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Bandwidth Spec Length      | Reverse Bandwidth Spec Length |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Bw Spec Type  |  Max-LSP      | Reserved                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Min Bandwidth Spec                                     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Min Reverse Bandwidth Spec (optional)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~                Optional   TLVs                                ~
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Bandwidth Spec Length (16 bits): the total length of the Min
   Bandwidth Spec field.  It is to be noted that the RSVP-TE traffic
   specification MAY also include TLV different from the PCEP TLVs.  The
   length MUST be strictly greater than 0.

   Reverse Bandwidth Spec Length (16 bits): the total length of the Min
   Reverse Bandwidth Spec field.  It MAY be equal to 0.

   Bw Spec Type (8 bits): the bandwidth specification type, it
   corresponds to the RSVP-TE SENDER_TSPEC (Object Class 12) C-Types.

   Max-LSP (8 bits): maximum number of TE-LSPs in the set.



Margaria, et al.         Expires March 31, 2019                [Page 10]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   Min Bandwidth Spec (variable): specifies the minimum bandwidth
   specification of each element of the TE-LSP set.

   Min Reverse Bandwidth Spec (variable): specifies the minimum reverse
   bandwidth specification of each element of the TE-LSP set.

   The encoding of the fields Min Bandwidth Spec and Min Reverse
   Bandwidth Spec is the same as in RSVP-TE SENDER_TSPEC object, it can
   be found in Table 2 from Section 2.3.

   When a PCC requests a bi-directional path with symetric bandwidth
   while specifying load balancing constraints it SHOULD specify the Min
   Bandwidth Spec field, and set the Reverse Bandwidth Spec Length to 0.
   When a PCC needs to request a bi-directional path with asymmetric
   bandwidth while specifying load balancing constraints, it MUST
   specify the different bandwidth in forward and reverse directions
   through a Min Bandwidth Spec and Min Reverse Bandwidth Spec fields.

   OPTIONAL TLVs MAY be included within the object body to specify more
   specific bandwidth requirements.  No TLVs for the Generalized Load
   Balancing object type are defined by this document.

   The semantic of the LOAD-BALANCING object is not changed.  If a PCC
   requests the computation of a set of TE-LSPs so that the total of
   their generalized bandwidth is X, the maximum number of TE-LSPs is N,
   and each TE-LSP must at least have a bandwidth of B, it inserts a
   BANDWIDTH object specifying X as the required bandwidth and a LOAD-
   BALANCING object with the Max-LSP and Min Bandwidth Spec fields set
   to N and B, respectively.

2.5.  END-POINTS Object Extensions

   The END-POINTS object is used in a PCEP request message to specify
   the source and the destination of the path for which a path
   computation is requested.  From [RFC5440], the source IP address and
   the destination IP address are used to identify those.  A new Object
   Type is defined to address the following possibilities:

   o  Different source and destination endpoint types.

   o  Label restrictions on the endpoint.

   o  Specification of unnumbered endpoints type as seen in GMPLS
      networks.

   The Object encoding is described in the following sections.

   In path computation within a GMPLS context the endpoints can:



Margaria, et al.         Expires March 31, 2019                [Page 11]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   o  Be unnumbered as described in [RFC3477].

   o  Have label(s) associated to them, specifying a set of constraints
      in the allocation of labels.

   o  Have different switching capabilities

   The IPv4 and IPv6 endpoints are used to represent the source and
   destination IP addresses.  The scope of the IP address (Node or
   numbered Link) is not explicitly stated.  It is also possible to
   request a Path between a numbered link and an unnumbered link, or a
   P2MP path between different type of endpoints.

   This document defines the Generalized Endpoint object type TBA-5 for
   the END-POINTS object.  This new type also supports the specification
   of constraints on the endpoint label to be used.  The PCE might know
   the interface restrictions but this is not a requirement.  This
   corresponds to requirements 6 and 10 of [RFC7025].

2.5.1.  Generalized Endpoint Object Type

   The Generalized Endpoint object type format consists of a body and a
   list of TLVs scoped to this object.  The TLVs give the details of the
   endpoints and are described in Section 2.5.2.  For each Endpoint
   Type, a different grammar is defined.  The TLVs defined to describe
   an endpoint are:

   1.  IPv4 address endpoint.

   2.  IPv6 address endpoint.

   3.  Unnumbered endpoint.

   4.  Label request.

   5.  Label set.

   The Label set TLV is used to restrict or suggest the label allocation
   in the PCE.  This TLVs express the set of restrictions which may
   apply to signaling.  Label restriction support can be an explicit or
   a suggested value (Label set describing one label, with the L bit
   respectively cleared or set), mandatory range restrictions (Label set
   with L bit cleared) and optional range restriction (Label set with L
   bit set).  Endpoints label restriction may not be part of the RRO or
   IRO, they can be included when following [RFC4003] in signaling for
   egress endpoint, but ingress endpoint properties can be local to the
   PCC and not signaled.  To support this case the label set allows to
   indicate which label are used in case of reoptimization.  The label



Margaria, et al.         Expires March 31, 2019                [Page 12]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   range restrictions are valid in GMPLS-controlled networks, either by
   PCC policy or depending on the switching technology used, for
   instance on given Ethernet or ODU equipment having limited hardware
   capabilities restricting the label range.  Label set restriction also
   applies to WSON networks where the optical senders and receivers are
   limited in their frequency tunability ranges, restricting then in
   GMPLS the possible label ranges on the interface.  The END-POINTS
   Object with Generalized Endpoint object type is encoded as follow:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |      Reserved                                 | Endpoint Type |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~                           TLVs                                ~
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Reserved bits SHOULD be set to 0 when a message is sent and ignored
   when the message is received.

   The Endpoint Type is defined as follow:

        Value   Type                Meaning

        0       Point-to-Point
        1       Point-to-Multipoint New leaves to add
        2                           Old leaves to remove
        3                           Old leaves whose path can be
                                    modified/reoptimized
        4                           Old leaves whose path has to be
                                    left unchanged
        5-244   Reserved
        245-255 Experimental range

               Table 3: Generalized Endpoint endpoint types

   The Endpoint Type is used to cover both point-to-point and different
   point-to-multipoint endpoints.  A PCE may accept only Endpoint Type
   0: Endpoint Types 1-4 apply if the PCE implementation supports P2MP
   path calculation.  A PCE not supporting a given Endpoint Type SHOULD
   respond with a PCErr with Error Type 4, Value TBD "Unsupported
   endpoint type in END-POINTS Generalized Endpoint object type".  As
   per [RFC5440], a PCE unable to process Generalized Endpoints may
   respond with Error Type 3 or 4, Value 2.  The TLVs present in the
   request object body MUST follow the following [RFC5511] grammar:



Margaria, et al.         Expires March 31, 2019                [Page 13]


Internet-Draft             PCEP Ext for GMPLS             September 2018


     <generalized-endpoint-tlvs>::=
       <p2p-endpoints> | <p2mp-endpoints>

     <p2p-endpoints> ::=
       <endpoint> [<endpoint-restriction-list>]
       <endpoint> [<endpoint-restriction-list>]

     <p2mp-endpoints> ::=
       <endpoint> [<endpoint-restriction-list>]
       [<endpoint> [<endpoint-restriction-list>]]...


   For endpoint type Point-to-Multipoint, several endpoint objects MAY
   be present in the message and each represents a leave, exact meaning
   depend on the endpoint type defined of the object.

   An endpoint is defined as follows:

    <endpoint>::=<IPV4-ADDRESS>|<IPV6-ADDRESS>|<UNNUMBERED-ENDPOINT>
    <endpoint-restriction-list> ::=               <endpoint-restriction>
                 [<endpoint-restriction-list>]

    <endpoint-restriction> ::=
                     <LABEL-REQUEST><label-restriction-list>

    <label-restriction-list> ::= <label-restriction>
                                 [<label-restriction-list>]
    <label-restriction> ::= <LABEL-SET>

   The different TLVs are described in the following sections.  A PCE
   MAY support IPV4-ADDRESS, IPV6-ADDRESS or UNNUMBERED-ENDPOINT TLVs.
   When receiving a PCReq, a PCE unable to resolve the identifier in one
   of those TLVs MUST respond using a PCRep with NO-PATH and set the bit
   "Unknown destination" or "Unknown source" in the NO-PATH-VECTOR TLV.
   The response SHOULD include the END-POINTS object with only the
   unsupported TLV(s).

   A PCE MAY support LABEL-REQUEST or LABEL-SET TLVs.  If a PCE finds a
   non-supported TLV in the END-POINTS the PCE MUST respond with a PCErr
   message with Error Type 4 error value="Unsupported TLV present in
   END-POINTS Generalized Endpoint object type" and the message SHOULD
   include the END-POINTS object in the response with only the endpoint
   and endpoint restriction TLV it did not understand.  A PCE supporting
   those TLVs but not being able to fulfil the label restriction MUST
   send a response with a NO-PATH object which has the bit "No endpoint
   label resource" or "No endpoint label resource in range" set in the
   NO-PATH-VECTOR TLV.  The response SHOULD include an END-POINTS object




Margaria, et al.         Expires March 31, 2019                [Page 14]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   containing only the TLV(s) related to the constraints the PCE could
   not meet.

2.5.2.  END-POINTS TLV Extensions

   All endpoint TLVs have the standard PCEP TLV header as defined in
   [RFC5440] section 7.1.  In this object type the order of the TLVs
   MUST be followed according to the object type definition.

2.5.2.1.  IPV4-ADDRESS TLV

   This TLV represents a numbered endpoint using IPv4 numbering, the
   format of the IPv4-ADDRESS TLV value (TLV-Type=TBA-6) is as follows:

      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          IPv4 address                         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   This TLV MAY be ignored, in which case a PCRep with NO-PATH SHOULD be
   responded, as described in Section 2.5.1.

2.5.2.2.  IPV6-ADDRESS TLV

   This TLV represents a numbered endpoint using IPV6 numbering, the
   format of the IPv6-ADDRESS TLV value (TLV-Type=TBA-7) is as follows:

      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |              IPv6 address (16 bytes)                          |
     |                                                               |
     |                                                               |
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   This TLV MAY be ignored, in which case a PCRep with NO-PATH SHOULD be
   responded, as described in Section 2.5.1.

2.5.2.3.  UNNUMBERED-ENDPOINT TLV

   This TLV represents an unnumbered interface.  This TLV has the same
   semantic as in [RFC3477].  The TLV value is encoded as follow (TLV-
   Type=TBA-8)






Margaria, et al.         Expires March 31, 2019                [Page 15]


Internet-Draft             PCEP Ext for GMPLS             September 2018


      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          LSR's Router ID                      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                       Interface ID (32 bits)                  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   This TLV MAY be ignored, in which case a PCRep with NO-PATH SHOULD be
   responded, as described in Section 2.5.1.

2.5.2.4.  LABEL-REQUEST TLV

   The LABEL-REQUEST TLV indicates the switching capability and encoding
   type of the following label restriction list for the endpoint.  Its
   format and encoding is the same as described in [RFC3471] Section 3.1
   Generalized label request.  The LABEL-REQUEST TLV use TLV-Type=TBA-9.
   The Encoding Type indicates the encoding type, e.g., SONET/SDH/GigE
   etc., of the LSP with which the data is associated.  The Switching
   type indicates the type of switching that is being requested on the
   endpoint.  G-PID identifies the payload.  This TLV and the following
   one are introduced to satisfy requirement 13 of [RFC7025] for the
   endpoint.  It is not directly related to the TE-LSP label request,
   which is expressed by the SWITCH-LAYER object.

   On the path calculation request only the Tspec and switch layer need
   to be coherent, the endpoint labels could be different (supporting a
   different Tspec).  Hence the label restrictions include a Generalized
   label request in order to interpret the labels.  This TLV MAY be
   ignored, in which case a PCRep with NO-PATH SHOULD be responded, as
   described in Section 2.5.1.

2.5.2.5.  Labels TLV

   Label or label range restrictions can be specified for the TE-LSP
   endpoints.  Those are encoded using the LABEL-SET TLV.  The label
   value need to be interpreted with a description on the Encoding and
   switching type.  The REQ-ADAP-CAP object from [RFC8282] can be used
   in case of mono-layer request, however in case of multilayer it is
   possible to have more than one object, so it is better to have a
   dedicated TLV for the label and label request.  Those TLV MAY be
   ignored, in which case a response with NO-PATH SHOULD be responded,
   as described in Section 2.5.1.  TLVs are encoded as follow (following
   [RFC5440]):

   o  LABEL-SET TLV, Type=TBA-10.  The TLV Length is variable, Encoding
      follows [RFC3471] Section 3.5 "Label set" with the addition of a U
      bit, O bit and L bit.  The L bit is used to represent a suggested



Margaria, et al.         Expires March 31, 2019                [Page 16]


Internet-Draft             PCEP Ext for GMPLS             September 2018


      set of label, following the semantic of SUGGESTED_LABEL defined by
      [RFC3471].  The U bit is set for upstream direction in case of
      bidirectional LSP and the O bit is used to represent a previously
      allocated label.

      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 |L|O|U|        Label Type         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          Subchannel 1                         |
     |                              ...                              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     :                               :                               :
     :                               :                               :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          Subchannel N                         |
     |                              ...                              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   A LABEL-SET TLV represents a set of possible labels that can be used
   on an interface.  If the L bit is cleared, the label allocated on the
   first endpoint MUST be within the label set range.  The action
   parameter in the Label set indicates the type of list provided.
   Those parameters are described by [RFC3471] section 3.5.1.

   The U, O and L bits have the following meaning:

   U: Upstream direction: set when the label or label set is in the
      reverse direction
   O: Old Label: set when the TLV represent the old label in case of re-
      optimization.  The R bit of the RP object MUST be set to 1. If the
      L bit is set, this bit SHOULD be set to 0 and ignored on receipt.
      When this bit is set, the Action field MUST be set to 0 (Inclusive
      List) and the Label Set MUST contain one subchannel.
   L: Loose Label: set when the TLV indicates to the PCE a set of
      preferred (ordered) labels to be used. The PCE MAY use those
      labels for label allocation.

                              Labels TLV bits

   Several LABEL_SET TLVs MAY be present with the O bit cleared,
   LABEL_SET TLVs with L bit set can be combined with a LABEL_SET TLV
   with L bit cleared.  At most 2 LABEL_SET TLVs MUST be present with
   the O bit set, at most one with the U bit set and at most one with
   the U bit cleared.  For a given U bit value, if more than one
   LABEL_SET TLV with the O bit set is present, the first TLV MUST be



Margaria, et al.         Expires March 31, 2019                [Page 17]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   processed and the following TLVs with the same U and O bit MUST be
   ignored.

   A LABEL-SET TLV with the O and L bit set MUST trigger a PCErr message
   with error type="Reception of an invalid object" error value="Wrong
   LABEL-SET TLV present with O and L bit set".

   A LABEL-SET TLV with the O bit set and an Action Field not set to 0
   (Inclusive list) or containing more than one subchannel MUST trigger
   a PCErr message with error type="Reception of an invalid object"
   error value="Wrong LABEL-SET TLV present with O bit and wrong
   format".

   If a LABEL-SET TLV is present with O bit set, the R bit of the RP
   object MUST be set, otherwise a PCErr message MUST be sent with error
   type="Reception of an invalid object" error value="LABEL-SET TLV
   present with O bit set but without R bit set in RP".

2.6.  IRO Extension

   The IRO as defined in [RFC5440] is used to include specific objects
   in the path.  RSVP-TE allows to include label definition, in order to
   fulfill requirement 13 of [RFC7025] the IRO needs to support the new
   subobject type as defined in [RFC3473]:

                             Type   Sub-object
                             TBA-38 LABEL

   The Label subobject MUST follow a subobject identifying a link,
   currently an IP address subobject (Type 1 or 2) or an interface ID
   (type 4) subobject.  If an IP address subobject is used, then the
   given IP address MUST be associated with a link.  More than one label
   subobject MAY follow each link subobject.  The procedure associated
   with this subobject is as follows.

   If the PCE is able to allocate labels (e.g. via explicit label
   control) the PCE MUST allocate one label from within the set of label
   values for the given link.  If the PCE does not assign labels, then
   it sends a response with a NO-PATH object, containing a NO-PATH-
   VECTOR TLV with the bit 'No label resource in range' set.

2.7.  XRO Extension

   The XRO as defined in [RFC5521] is used to exclude specific objects
   in the path.  RSVP-TE allows to exclude labels ([RFC6001]), in order
   to fulfill requirement 13 of [RFC7025] section 3.1, the PCEP's XRO
   needs to support a new subobject to enable label exclusion.




Margaria, et al.         Expires March 31, 2019                [Page 18]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   The encoding of the XRO Label subobject follows the encoding of the
   Label ERO subobject defined in [RFC3473] and XRO subobject defined in
   [RFC5521].  The XRO Label subobject represent one Label and is
   defined as follows:

   XRO Subobject Type TBA-39: Label Subobject.

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |X| Type=TBA-39 |    Length     |U|   Reserved  |   C-Type      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Label                             |
   |                              ...                              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      X (1 bit): as per [RFC5521].  The X-bit indicates whether the
      exclusion is mandatory or desired.  0 indicates that the resource
      specified MUST be excluded from the path computed by the PCE. 1
      indicates that the resource specified SHOULD be excluded from the
      path computed by the PCE, but MAY be included subject to PCE
      policy and the absence of a viable path that meets the other
      constraints and excludes the resource.

      Type (7 bits): The Type of the XRO Label subobject is TBA-39,
      suggested value 3.

      Length (8 bits): see [RFC5521], the total length of the subobject
      in bytes (including the Type and Length fields).  The Length is
      always divisible by 4.

      U (1 bit): see [RFC3471].

      C-Type (8 bits): the C-Type of the included Label Object as
      defined in [RFC3471].

      Label: see [RFC3471].

   The Label subobject MUST follow a subobject identifying a link,
   currently an IP address subobject (Type 1 or 2) or an interface ID
   (type 4) subobject.  If an IP address subobject is used, then the
   given IP address MUST be associated with a link.  More than one label
   subobject MAY follow each link subobject.

                              Type Sub-object
                              3    LABEL





Margaria, et al.         Expires March 31, 2019                [Page 19]


Internet-Draft             PCEP Ext for GMPLS             September 2018


2.8.  LSPA Extensions

   The LSPA carries the LSP attributes.  In the end-to-end recovery
   context, this also includes the protection state information.  This
   object is introduced to fulfill requirement 7 of [RFC7025] section
   3.1 and requirement 3 of [RFC7025] section 3.2.  This object contains
   the information of the PROTECTION object defined by [RFC4872] and can
   be used as a policy input.  The LSPA object MAY carry a PROTECTION-
   ATTRIBUTE TLV defined as: Type TBA-12: PROTECTION-ATTRIBUTE

      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                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |S|P|N|O|  Reserved | LSP Flags |     Reserved      | Link Flags|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |I|R|   Reserved    | Seg.Flags |           Reserved            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The content is as defined in [RFC4872], [RFC4873].

   LSP (protection) Flags or Link flags field can be used by a PCE
   implementation for routing policy input.  The other attributes are
   only meaningful for a stateful PCE.

   This TLV is OPTIONAL and MAY be ignored by the PCE, in which case it
   MUST NOT include the TLV in the LSPA, if present, of the response.
   When the TLV is used by the PCE, a LSPA object and the PROTECTION-
   ATTRIBUTE TLV MUST be included in the response.  Fields that were not
   considered MUST be set to 0.

2.9.  NO-PATH Object Extension

   The NO-PATH object is used in PCRep messages in response to an
   unsuccessful path computation request (the PCE could not find a path
   satisfying the set of constraints).  In this scenario, PCE MUST
   include a NO-PATH object in the PCRep message.  The NO-PATH object
   MAY carries the NO-PATH-VECTOR TLV that specifies more information on
   the reasons that led to a negative reply.  In case of GMPLS networks
   there could be some additional constraints that led to the failure
   like protection mismatch, lack of resources, and so on.  Few new
   flags have been introduced in the 32-bit flag field of the NO-PATH-
   VECTOR TLV and no modifications have been made in the NO-PATH object.







Margaria, et al.         Expires March 31, 2019                [Page 20]


Internet-Draft             PCEP Ext for GMPLS             September 2018


2.9.1.  Extensions to NO-PATH-VECTOR TLV

   The modified NO-PATH-VECTOR TLV carrying the additional information
   is as follows:

      Bit number TBA-32 - Protection Mismatch (1-bit).  Specifies the
      mismatch of the protection type in the PROTECTION-ATTRIBUTE TLV in
      the request.

      Bit number TBA-33 - No Resource (1-bit).  Specifies that the
      resources are not currently sufficient to provide the path.

      Bit number TBA-34 - Granularity not supported (1-bit).  Specifies
      that the PCE is not able to provide a path with the requested
      granularity.

      Bit number TBA-35 - No endpoint label resource (1-bit).  Specifies
      that the PCE is not able to provide a path because of the endpoint
      label restriction.

      Bit number TBA-36 - No endpoint label resource in range (1-bit).
      Specifies that the PCE is not able to provide a path because of
      the endpoint label set restriction.

      Bit number TBA-37 - No label resource in range (1-bit).  Specifies
      that the PCE is not able to provide a path because of the label
      set restriction.

3.  Additional Error-Types and Error-Values Defined

   A PCEP-ERROR object is used to report a PCEP error and is
   characterized by an Error-Type that specifies the type of error while
   Error-value that provides additional information about the error.  An
   additional error type and few error values are defined to represent
   some of the errors related to the newly identified objects related to
   GMPLS networks.  For each PCEP error, an Error-Type and an Error-
   value are defined.  Error-Type 1 to 10 are already defined in
   [RFC5440].  Additional Error- values are defined for Error-Types 4
   and 10.  A new Error-Type is introduced (value TBA-27).












Margaria, et al.         Expires March 31, 2019                [Page 21]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   Error-Type Error-value

       4      Not supported
              object
              value=TBA-14: Bandwidth Object type TBA-2 or TBA-3 not
                            supported.
              value=TBA-15: Unsupported endpoint type in
                            END-POINTS Generalized Endpoint
                            object type.
              value=TBA-16: Unsupported TLV present in END-POINTS
                            Generalized Endpoint object type.
              value=TBA-17: Unsupported granularity in the RP object
                            flags.
       10     Reception of
              an invalid
              object
              value=TBA-18: Bad Bandwidth Object type TBA-2(Generalized
                            bandwidth) or TBA-3( Generalized bandwidth
                            of existing TE-LSP for which a
                            reoptimization is requested).
              value=TBA-19: Unsupported LSP Protection Type in
                            PROTECTION-ATTRIBUTE TLV.
              value=TBA-20: Unsupported LSP Protection Flags in
                            PROTECTION-ATTRIBUTE TLV.
              value=TBA-21: Unsupported Secondary LSP Protection Flags
                            in PROTECTION-ATTRIBUTE TLV.
              value=TBA-22: Unsupported Link Protection Type in
                            PROTECTION-ATTRIBUTE TLV.
              value=TBA-23: Unsupported Link Protection Type in
                            PROTECTION-ATTRIBUTE TLV.
              value=TBA-24: LABEL-SET TLV present with 0 bit set but
                            without R bit set in RP.
              value=TBA-25: Wrong LABEL-SET
                            TLV present with
                            0 and L bit set.
              value=TBA-26: Wrong LABEL-SET with O bit set and wrong
                            format.
     TBA-27   Path
              computation
              failure
              value=0:      Unassigned.
              value=TBA-28: Unacceptable request message.
              value=TBA-29: Generalized bandwidth value not supported.
              value=TBA-30: Label Set constraint could not be
                            met.
              value=TBA-31: Label constraint could not be
                            met.




Margaria, et al.         Expires March 31, 2019                [Page 22]


Internet-Draft             PCEP Ext for GMPLS             September 2018


4.  Manageability Considerations

   This section follows the guidance of [RFC6123].

4.1.  Control of Function through Configuration and Policy

   This document makes no change to the basic operation of PCEP and so
   the requirements described in [RFC5440] Section 8.1. also apply to
   this document.  In addition to those requirements a PCEP
   implementation may allow the configuration of the following
   parameters:

      Accepted RG in the RP object.

      Default RG to use (overriding the one present in the PCReq)

      Accepted BANDWIDTH object type TBA-2 and TBA-3 parameters in
      request, default mapping to use when not specified in the request

      Accepted LOAD-BALANCING object type TBA-4 parameters in request.

      Accepted endpoint type and allowed TLVs in object END-POINTS with
      object type Generalized Endpoint.

      Accepted range for label restrictions in label restriction in END-
      POINTS, or IRO or XRO objects

      PROTECTION-ATTRIBUTE TLV acceptance and suppression.

   Those parameters configuration are applicable to the different
   sessions as described in [RFC5440] Section 8.1 (by default, per PCEP
   peer, etc.).

4.2.  Information and Data Models

   This document makes no change to the basic operation of PCEP and so
   the requirements described in [RFC5440] Section 8.2. also apply to
   this document.  This document does not introduces new ERO sub object,
   ERO information model is already covered in [RFC4802].

4.3.  Liveness Detection and Monitoring

   This document makes no change to the basic operation of PCEP and so
   there are no changes to the requirements for liveness detection and
   monitoring set out in [RFC4657] and [RFC5440] Section 8.3.






Margaria, et al.         Expires March 31, 2019                [Page 23]


Internet-Draft             PCEP Ext for GMPLS             September 2018


4.4.  Verifying Correct Operation

   This document makes no change to the basic operations of PCEP and
   considerations described in [RFC5440] Section 8.4.  New errors
   introduced by this document should be covered by the requirement to
   log error events.

4.5.  Requirements on Other Protocols and Functional Components

   No new Requirements on Other Protocols and Functional Components are
   made by this document.  This document does not require ERO object
   extensions.  Any new ERO subobject defined in the TEAS or CCAMP
   working group can be adopted without modifying the operations defined
   in this document.

4.6.  Impact on Network Operation

   This document makes no change to the basic operations of PCEP and
   considerations described in [RFC5440] Section 8.6.  In addition to
   the limit on the rate of messages sent by a PCEP speaker, a limit MAY
   be placed on the size of the PCEP messages.

5.  IANA Considerations

   IANA assigns values to the PCEP protocol objects and TLVs.  IANA is
   requested to make some allocations for the newly defined objects and
   TLVs introduced in this document.  Also, IANA is requested to manage
   the space of flags that are newly added in the TLVs.

5.1.  PCEP Objects

   As described in Section 2.3, Section 2.4 and Section 2.5.1 new
   Objects types are defined.  IANA is requested to make the following
   Object-Type allocations from the "PCEP Objects" sub-registry.

















Margaria, et al.         Expires March 31, 2019                [Page 24]


Internet-Draft             PCEP Ext for GMPLS             September 2018


    Object      5
    Class
    Name        BANDWIDTH
    Object-Type TBA-2: Generalized bandwidth
                TBA-3: Generalized bandwidth of an existing TE-LSP for
                which a reoptimization is requested
    Reference   This document (section Section 2.3)

    Object      14
    Class
    Name        LOAD-BALANCING
    Object-Type TBA-4: Generalized Load Balancing

    Reference   This document (section Section 2.4)
    Object      4
    Class
    Name        END-POINTS
    Object-Type TBA-5: Generalized Endpoint
    Reference   This document (section Section 2.5)

5.2.  END-POINTS Object, Object Type Generalized Endpoint

   IANA is requested to create a registry to manage the Endpoint Type
   field of the END-POINTS object, Object Type Generalized Endpoint and
   manage the code space.

   New endpoint type in the Reserved range MAY be allocated by an IETF
   consensus action.  Each endpoint type should be tracked with the
   following qualities:

   o  Endpoint type

   o  Description

   o  Defining RFC

   New endpoint type in the Experimental range are for experimental use;
   these will not be registered with IANA and MUST NOT be mentioned by
   RFCs.

   The following values have been defined by this document.
   (Section 2.5.1, Table 3):









Margaria, et al.         Expires March 31, 2019                [Page 25]


Internet-Draft             PCEP Ext for GMPLS             September 2018


        Value   Type                Meaning

        0       Point-to-Point
        1       Point-to-Multipoint New leaves to add
        2                           Old leaves to remove
        3                           Old leaves whose path can be
                                    modified/reoptimized
        4                           Old leaves whose path has to be
                                    left unchanged
        5-244   Reserved
        245-255 Experimental range

5.3.  New PCEP TLVs

   IANA manages the PCEP TLV code point registry (see [RFC5440]).  This
   is maintained as the "PCEP TLV Type Indicators" sub-registry of the
   "Path Computation Element Protocol (PCEP) Numbers" registry.  This
   document defines new PCEP TLVs, to be carried in the END-POINTS
   object with Generalized Endpoint object Type.  IANA is requested to
   do the following allocation.  The values here are suggested for use
   by IANA.

    Value  Meaning              Reference

    TBA-6  IPV4-ADDRESS         This document (section Section 2.5.2.1)
    TBA-7  IPV6-ADDRESS         This document (section Section 2.5.2.2)
    TBA-8  UNNUMBERED-ENDPOINT  This document (section Section 2.5.2.3)
    TBA-9  LABEL-REQUEST        This document (section Section 2.5.2.4)
    TBA-10 LABEL-SET            This document (section Section 2.5.2.5)
    TBA-11 SUGGESTED-LABEL-SET  This document (section Section 2.5.2.5)
    TBA-12 PROTECTION-ATTRIBUTE This document (section Section 2.8)
    TBA-1  GMPLS-CAPABILITY     This document (section Section 2.1.2)

5.4.  RP Object Flag Field

   As described in Section 2.2 new flag are defined in the RP Object
   Flag IANA is requested to make the following Object-Type allocations
   from the "RP Object Flag Field" sub-registry.  The values here are
   suggested for use by IANA.

             Bit           Description           Reference

    TBA-13 (suggested bit  routing granularity   This document, Section
            17-16)         (RG)                  2.2







Margaria, et al.         Expires March 31, 2019                [Page 26]


Internet-Draft             PCEP Ext for GMPLS             September 2018


5.5.  New PCEP Error Codes

   As described in Section 3, new PCEP Error-Types and Error-values are
   defined.  IANA is requested to make the following allocation in the
   "PCEP-ERROR Object Error Types and Values" registry.  The values here
   are suggested for use by IANA.

   Error         name                                      Reference

   Type=4        Not supported object                      [RFC5440]
   Value=TBA-14: Bandwidth Object type TBA or TBA not      This Document
                 supported.
   Value=TBA-15: Unsupported endpoint type in END-POINTS   This Document
                 Generalized Endpoint object type
   Value=TBA-16: Unsupported TLV present in END-POINTS     This Document
                 Generalized Endpoint object type
   Value=TBA-17: Unsupported granularity in the RP object  This Document
                 flags
   Type=10       Reception of an invalid object            [RFC5440]
   Value=TBA-18: Bad Bandwidth Object type                 This Document
                 TBA-2(Generalized bandwidth) or
                 TBA-3(Generalized bandwidth of existing
                 TE-LSP for which a reoptimization is
                 requested).
   Value=TBA-19: Unsupported LSP Protection Type in        This Document
                 PROTECTION-ATTRIBUTE TLV.
   Value=TBA-20: Unsupported LSP Protection Flags in       This Document
                 PROTECTION-ATTRIBUTE TLV.
   Value=TBA-21: Unsupported Secondary LSP Protection      This Document
                 Flags in PROTECTION-ATTRIBUTE TLV.
   Value=TBA-22: Unsupported Link Protection Type in       This Document
                 PROTECTION-ATTRIBUTE TLV.
   Value=TBA-23: Unsupported Link Protection Type in       This Document
                 PROTECTION-ATTRIBUTE TLV.
   Value=TBA-24: LABEL-SET TLV present with 0 bit set but  This Document
                 without R bit set in RP.
   Value=TBA-25: Wrong LABEL-SET TLV present with 0 and L  This Document
                 bit set.
   Value=TBA-26: Wrong LABEL-SET with O bit set and wrong  This Document
                 format.
   Type=TBA-27   Path computation failure                  This Document
   Value=0       Unassigned.                               This Document
   Value=TBA-28: Unacceptable request message.             This Document
   Value=TBA-29: Generalized bandwidth value not           This Document
                 supported.
   Value=TBA-30: Label Set constraint could not be met.    This Document
   Value=TBA-31: Label constraint could not be met.        This Document




Margaria, et al.         Expires March 31, 2019                [Page 27]


Internet-Draft             PCEP Ext for GMPLS             September 2018


5.6.  New NO-PATH-VECTOR TLV Fields

   As described in Section 2.9.1, new NO-PATH-VECTOR TLV Flag Fields
   have been defined.  IANA is requested to do the following allocations
   in the "NO-PATH-VECTOR TLV Flag Field" sub-registry.  The values here
   are suggested for use by IANA.

      Bit number TBA-32 - Protection Mismatch (1-bit).  Specifies the
      mismatch of the protection type of the PROTECTION-ATTRIBUTE TLV in
      the request.

      Bit number TBA-33 - No Resource (1-bit).  Specifies that the
      resources are not currently sufficient to provide the path.

      Bit number TBA-34 - Granularity not supported (1-bit).  Specifies
      that the PCE is not able to provide a path with the requested
      granularity.

      Bit number TBA-35 - No endpoint label resource (1-bit).  Specifies
      that the PCE is not able to provide a path because of the endpoint
      label restriction.

      Bit number TBA-36 - No endpoint label resource in range (1-bit).
      Specifies that the PCE is not able to provide a path because of
      the endpoint label set restriction.

      Bit number TBA-37 - No label resource in range (1-bit).  Specifies
      that the PCE is not able to provide a path because of the label
      set restriction.

5.7.  New Subobject for the Include Route Object

   The "PCEP Parameters" registry contains a subregistry "PCEP Objects"
   with an entry for the Include Route Object (IRO).

   IANA is requested to add a further subobject that can be carried in
   the IRO as follows:

            Subobject                 type            Reference

            TBA-38, suggested value 3 Label subobject [RFC3473]

5.8.  New Subobject for the Exclude Route Object

   The "PCEP Parameters" registry contains a subregistry "PCEP Objects"
   with an entry for the XRO object (Exclude Route Object).





Margaria, et al.         Expires March 31, 2019                [Page 28]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   IANA is requested to add a further subobject that can be carried in
   the XRO as follows:

            Subobject                 type            Reference

            TBA-39, suggested value 3 Label subobject [RFC3473]

6.  Security Considerations

   GMPLS controls multiple technologies and types of network elements.
   The LSPs that are established using GMPLS, whose paths can be
   computed using the PCEP extensions to support GMPLS described in this
   document, can carry a high amount of traffic and can be a critical
   part of a network infrastructure.  The PCE can then play a key role
   in the use of the resources and in determining the physical paths of
   the LSPs and thus it is important to ensure the identity of PCE and
   PCC, as well as the communication channel.  In many deployments there
   will be a completely isolated network where an external attack is of
   very low probability.  However, there are other deployment cases in
   which the PCC-PCE communication can be more exposed and there could
   be more security considerations.  Three main situations in case of an
   attack in the GMPLS PCE context could happen:

   o  PCE Identity theft: A legitimate PCC could requests a path for a
      GMPLS LSP to a malicious PCE, which poses as a legitimate PCE.
      The answer can make that the LSP traverses some geographical place
      known to the attacker where some sniffing devices could be
      installed.  Also, the answer can omit constraints given in the
      requests (e.g. excluding certain fibers, avoiding some SRLGs)
      which could make that the LSP which will be later set-up can look
      perfectly fine, but will be in a risky situation.  Also, the
      answer can lead to provide a LSP that does not provide the desired
      quality and gives less resources tan necessary.

   o  PCC Identity theft: A malicious PCC, acting as a legitimate PCC,
      requesting LSP paths to a legitimate PCE can obtain a good
      knowledge of the physical topology of a critical infrastructure.
      It could get to know enough details to plan a later physical
      attack.

   o  Message deciphering: As in the previous case, knowledge of an
      infrastructure can be obtained by sniffing PCEP messages.

   The security mechanisms can provide authentication and
   confidentiality for those scenarios where the PCC-PCE communication
   cannot be completely trusted.  Authentication can provide origin
   verification, message integrity and replay protection, while




Margaria, et al.         Expires March 31, 2019                [Page 29]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   confidentiality ensures that a third party cannot decipher the
   contents of a message.

   The document [RFC8253] describes the usage of Transport Layer
   Security (TLS) to enhance PCEP security.  The document describes the
   initiation of the TLS procedures, the TLS handshake mechanisms, the
   TLS methods for peer authentication, the applicable TLS ciphersuites
   for data exchange, and the handling of errors in the security checks.

   Finally, as mentioned by [RFC7025] the PCEP extensions to support
   GMPLS should be considered under the same security as current PCE
   work and this extension will not change the underlying security
   issues.  However, given the critical nature of the network
   infrastructures under control by GMPLS, the security issues described
   above should be seriously considered when deploying a GMPLS-PCE based
   control plane for such networks.  For more information on the
   security considerations on a GMPLS control plane, not only related to
   PCE/PCEP, [RFC5920] provides an overview of security vulnerabilities
   of a GMPLS control plane.

7.  Contributing Authors

   Elie Sfeir
   Coriant
   St Martin Strasse 76
   Munich, 81541
   Germany

   Email: elie.sfeir@coriant.com

   Franz Rambach
   Nockherstrasse 2-4,
   Munich 81541
   Germany

   Phone: +49 178 8855738
   Email: franz.rambach@cgi.com

   Francisco Javier Jimenez Chico
   Telefonica Investigacion y Desarrollo
   C/ Emilio Vargas 6
   Madrid, 28043
   Spain

   Phone: +34 91 3379037
   Email: fjjc@tid.es

   Huawei Technologies



Margaria, et al.         Expires March 31, 2019                [Page 30]


Internet-Draft             PCEP Ext for GMPLS             September 2018


      Suresh BR
      Shenzhen
      China
      Email: sureshbr@huawei.com


      Young Lee
      1700 Alma Drive, Suite 100
      Plano, TX 75075
      USA

      Phone: (972) 509-5599 (x2240)
      Email: ylee@huawei.com


      SenthilKumar S
      Shenzhen
      China
      Email: senthilkumars@huawei.com


      Jun Sun
      Shenzhen
      China
      Email: johnsun@huawei.com


   CTTC - Centre Tecnologic de Telecomunicacions de Catalunya

      Ramon Casellas
      PMT Ed B4 Av.  Carl Friedrich Gauss 7
      08860 Castelldefels (Barcelona)
      Spain
      Phone: (34) 936452916
      Email: ramon.casellas@cttc.es


8.  Acknowledgments

   The research of Ramon Casellas, Francisco Javier Jimenez Chico, Oscar
   Gonzalez de Dios, Cyril Margaria, and Franz Rambach leading to these
   results has received funding from the European Community's Seventh
   Framework Program FP7/2007-2013 under grant agreement no 247674 and
   no 317999.

   The authors would like to thank Julien Meuric, Lyndon Ong, Giada
   Lander, Jonathan Hardwick and Diego Lopez for their useful comments
   to the document.



Margaria, et al.         Expires March 31, 2019                [Page 31]


Internet-Draft             PCEP Ext for GMPLS             September 2018


9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC2210]  Wroclawski, J., "The Use of RSVP with IETF Integrated
              Services", RFC 2210, DOI 10.17487/RFC2210, September 1997,
              <https://www.rfc-editor.org/info/rfc2210>.

   [RFC3471]  Berger, L., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Functional Description",
              RFC 3471, DOI 10.17487/RFC3471, January 2003,
              <https://www.rfc-editor.org/info/rfc3471>.

   [RFC3473]  Berger, L., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Resource ReserVation Protocol-
              Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
              DOI 10.17487/RFC3473, January 2003,
              <https://www.rfc-editor.org/info/rfc3473>.

   [RFC3477]  Kompella, K. and Y. Rekhter, "Signalling Unnumbered Links
              in Resource ReSerVation Protocol - Traffic Engineering
              (RSVP-TE)", RFC 3477, DOI 10.17487/RFC3477, January 2003,
              <https://www.rfc-editor.org/info/rfc3477>.

   [RFC4003]  Berger, L., "GMPLS Signaling Procedure for Egress
              Control", RFC 4003, DOI 10.17487/RFC4003, February 2005,
              <https://www.rfc-editor.org/info/rfc4003>.

   [RFC4328]  Papadimitriou, D., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Extensions for G.709 Optical
              Transport Networks Control", RFC 4328,
              DOI 10.17487/RFC4328, January 2006,
              <https://www.rfc-editor.org/info/rfc4328>.

   [RFC4606]  Mannie, E. and D. Papadimitriou, "Generalized Multi-
              Protocol Label Switching (GMPLS) Extensions for
              Synchronous Optical Network (SONET) and Synchronous
              Digital Hierarchy (SDH) Control", RFC 4606,
              DOI 10.17487/RFC4606, August 2006,
              <https://www.rfc-editor.org/info/rfc4606>.






Margaria, et al.         Expires March 31, 2019                [Page 32]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   [RFC4802]  Nadeau, T., Ed., Farrel, A., and , "Generalized
              Multiprotocol Label Switching (GMPLS) Traffic Engineering
              Management Information Base", RFC 4802,
              DOI 10.17487/RFC4802, February 2007,
              <https://www.rfc-editor.org/info/rfc4802>.

   [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, DOI 10.17487/RFC4872, May 2007,
              <https://www.rfc-editor.org/info/rfc4872>.

   [RFC4873]  Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel,
              "GMPLS Segment Recovery", RFC 4873, DOI 10.17487/RFC4873,
              May 2007, <https://www.rfc-editor.org/info/rfc4873>.

   [RFC5088]  Le Roux, JL., Ed., Vasseur, JP., Ed., Ikejiri, Y., and R.
              Zhang, "OSPF Protocol Extensions for Path Computation
              Element (PCE) Discovery", RFC 5088, DOI 10.17487/RFC5088,
              January 2008, <https://www.rfc-editor.org/info/rfc5088>.

   [RFC5089]  Le Roux, JL., Ed., Vasseur, JP., Ed., Ikejiri, Y., and R.
              Zhang, "IS-IS Protocol Extensions for Path Computation
              Element (PCE) Discovery", RFC 5089, DOI 10.17487/RFC5089,
              January 2008, <https://www.rfc-editor.org/info/rfc5089>.

   [RFC5440]  Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol (PCEP)", RFC 5440,
              DOI 10.17487/RFC5440, March 2009,
              <https://www.rfc-editor.org/info/rfc5440>.

   [RFC5511]  Farrel, A., "Routing Backus-Naur Form (RBNF): A Syntax
              Used to Form Encoding Rules in Various Routing Protocol
              Specifications", RFC 5511, DOI 10.17487/RFC5511, April
              2009, <https://www.rfc-editor.org/info/rfc5511>.

   [RFC5520]  Bradford, R., Ed., Vasseur, JP., and A. Farrel,
              "Preserving Topology Confidentiality in Inter-Domain Path
              Computation Using a Path-Key-Based Mechanism", RFC 5520,
              DOI 10.17487/RFC5520, April 2009,
              <https://www.rfc-editor.org/info/rfc5520>.

   [RFC5521]  Oki, E., Takeda, T., and A. Farrel, "Extensions to the
              Path Computation Element Communication Protocol (PCEP) for
              Route Exclusions", RFC 5521, DOI 10.17487/RFC5521, April
              2009, <https://www.rfc-editor.org/info/rfc5521>.





Margaria, et al.         Expires March 31, 2019                [Page 33]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   [RFC5541]  Le Roux, JL., Vasseur, JP., and Y. Lee, "Encoding of
              Objective Functions in the Path Computation Element
              Communication Protocol (PCEP)", RFC 5541,
              DOI 10.17487/RFC5541, June 2009,
              <https://www.rfc-editor.org/info/rfc5541>.

   [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, DOI 10.17487/RFC6001, October 2010,
              <https://www.rfc-editor.org/info/rfc6001>.

   [RFC6003]  Papadimitriou, D., "Ethernet Traffic Parameters",
              RFC 6003, DOI 10.17487/RFC6003, October 2010,
              <https://www.rfc-editor.org/info/rfc6003>.

   [RFC6205]  Otani, T., Ed. and D. Li, Ed., "Generalized Labels for
              Lambda-Switch-Capable (LSC) Label Switching Routers",
              RFC 6205, DOI 10.17487/RFC6205, March 2011,
              <https://www.rfc-editor.org/info/rfc6205>.

   [RFC6387]  Takacs, A., Berger, L., Caviglia, D., Fedyk, D., and J.
              Meuric, "GMPLS Asymmetric Bandwidth Bidirectional Label
              Switched Paths (LSPs)", RFC 6387, DOI 10.17487/RFC6387,
              September 2011, <https://www.rfc-editor.org/info/rfc6387>.

   [RFC7139]  Zhang, F., Ed., Zhang, G., Belotti, S., Ceccarelli, D.,
              and K. Pithewan, "GMPLS Signaling Extensions for Control
              of Evolving G.709 Optical Transport Networks", RFC 7139,
              DOI 10.17487/RFC7139, March 2014,
              <https://www.rfc-editor.org/info/rfc7139>.

   [RFC7792]  Zhang, F., Zhang, X., Farrel, A., Gonzalez de Dios, O.,
              and D. Ceccarelli, "RSVP-TE Signaling Extensions in
              Support of Flexi-Grid Dense Wavelength Division
              Multiplexing (DWDM) Networks", RFC 7792,
              DOI 10.17487/RFC7792, March 2016,
              <https://www.rfc-editor.org/info/rfc7792>.

   [RFC8253]  Lopez, D., Gonzalez de Dios, O., Wu, Q., and D. Dhody,
              "PCEPS: Usage of TLS to Provide a Secure Transport for the
              Path Computation Element Communication Protocol (PCEP)",
              RFC 8253, DOI 10.17487/RFC8253, October 2017,
              <https://www.rfc-editor.org/info/rfc8253>.







Margaria, et al.         Expires March 31, 2019                [Page 34]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   [RFC8282]  Oki, E., Takeda, T., Farrel, A., and F. Zhang, "Extensions
              to the Path Computation Element Communication Protocol
              (PCEP) for Inter-Layer MPLS and GMPLS Traffic
              Engineering", RFC 8282, DOI 10.17487/RFC8282, December
              2017, <https://www.rfc-editor.org/info/rfc8282>.

9.2.  Informative References

   [RFC4655]  Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
              Element (PCE)-Based Architecture", RFC 4655,
              DOI 10.17487/RFC4655, August 2006,
              <https://www.rfc-editor.org/info/rfc4655>.

   [RFC4657]  Ash, J., Ed. and J. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol Generic
              Requirements", RFC 4657, DOI 10.17487/RFC4657, September
              2006, <https://www.rfc-editor.org/info/rfc4657>.

   [RFC5920]  Fang, L., Ed., "Security Framework for MPLS and GMPLS
              Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010,
              <https://www.rfc-editor.org/info/rfc5920>.

   [RFC6123]  Farrel, A., "Inclusion of Manageability Sections in Path
              Computation Element (PCE) Working Group Drafts", RFC 6123,
              DOI 10.17487/RFC6123, February 2011,
              <https://www.rfc-editor.org/info/rfc6123>.

   [RFC7025]  Otani, T., Ogaki, K., Caviglia, D., Zhang, F., and C.
              Margaria, "Requirements for GMPLS Applications of PCE",
              RFC 7025, DOI 10.17487/RFC7025, September 2013,
              <https://www.rfc-editor.org/info/rfc7025>.

   [RFC7449]  Lee, Y., Ed., Bernstein, G., Ed., Martensson, J., Takeda,
              T., Tsuritani, T., and O. Gonzalez de Dios, "Path
              Computation Element Communication Protocol (PCEP)
              Requirements for Wavelength Switched Optical Network
              (WSON) Routing and Wavelength Assignment", RFC 7449,
              DOI 10.17487/RFC7449, February 2015,
              <https://www.rfc-editor.org/info/rfc7449>.

Appendix A.  LOAD-BALANCING Usage for SDH Virtual Concatenation

   For example a request for one co-signaled n x VC-4 TE-LSP will not
   use the LOAD-BALANCING.  In case the VC-4 components can use
   different paths, the BANDWIDTH with object type TBA-2 will contain a
   traffic specification indicating the complete n x VC-4 traffic
   specification and the LOAD-BALANCING the minimum co-signaled VC-4.
   For an SDH network, a request to have a TE-LSP group with 10 VC-4



Margaria, et al.         Expires March 31, 2019                [Page 35]


Internet-Draft             PCEP Ext for GMPLS             September 2018


   containers, each path using at minimum 2 x VC-4 containers, can be
   represented with a BANDWIDTH object with OT=TBA-2, Bw Spec Type set
   to 4, the content of the Generalized Bandwidth is ST=6, RCC=0, NCC=0,
   NVC=10, MT=1.  The LOAD-BALANCING, OT=TBA-4 with Bw Spec Type set to
   4, Max-LSP=5, Min Bandwidth Spec is (ST=6, RCC=0, NCC=0, NVC=2,
   MT=1).  The PCE can respond with a response with maximum 5 paths,
   each of them having a BANDWIDTH OT=TBA-2 and Generalized Bandwidth
   matching the Min Bandwidth Spec from the LOAD-BALANCING object of the
   corresponding request.

Authors' Addresses

   Cyril Margaria (editor)
   Juniper
   1133 Innovation Way,
   Sunnyvale, CA  94089
   USA

   Email: cmargaria@juniper.net


   Oscar Gonzalez de Dios (editor)
   Telefonica Investigacion y Desarrollo
   C/ Ronda de la Comunicacion
   Madrid  28050
   Spain

   Phone: +34 91 4833441
   Email: oscar.gonzalezdedios@telefonica.com


   Fatai Zhang (editor)
   Huawei Technologies
   F3-5-B R&D Center, Huawei Base
   Bantian, Longgang District
   Shenzhen  518129
   P.R.China

   Email: zhangfatai@huawei.com












Margaria, et al.         Expires March 31, 2019                [Page 36]


Html markup produced by rfcmarkup 1.127, available from https://tools.ietf.org/tools/rfcmarkup/