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PCEP Extensions for MPLS-TE LSP Automatic Bandwidth Adjustment with stateful PCE
draft-dhody-pce-stateful-pce-auto-bandwidth-04

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This is an older version of an Internet-Draft whose latest revision state is "Replaced".
Authors Dhruv Dhody , Udayasree Palle , Ravi Singh
Last updated 2015-03-06
Replaced by draft-ietf-pce-stateful-pce-auto-bandwidth, RFC 8733
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draft-dhody-pce-stateful-pce-auto-bandwidth-04
PCE Working Group                                               D. Dhody
Internet-Draft                                                  U. Palle
Intended status: Standards Track                     Huawei Technologies
Expires: September 6, 2015                                      R. Singh
                                                        Juniper Networks
                                                           March 5, 2015

  PCEP Extensions for MPLS-TE LSP Automatic Bandwidth Adjustment with
                              stateful PCE
             draft-dhody-pce-stateful-pce-auto-bandwidth-04

Abstract

   The Path Computation Element Communication Protocol (PCEP) provides
   mechanisms for Path Computation Elements (PCEs) to perform path
   computations in response to Path Computation Clients (PCCs) requests.
   The stateful PCE extensions provide stateful control of Multiprotocol
   Label Switching (MPLS) Traffic Engineering Label Switched Paths (TE
   LSP) via PCEP, for a model where the PCC delegates control over one
   or more locally configured LSPs to the PCE.

   This document describes the automatic bandwidth adjustment of such
   LSPs under the Active Stateful PCE model.

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 http://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 September 6, 2015.

Copyright Notice

   Copyright (c) 2015 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Motivation  . . . . . . . . . . . . . . . . . . . . . . . . .   5
   4.  Architectural Overview  . . . . . . . . . . . . . . . . . . .   5
     4.1.  Auto-Bandwidth Overview . . . . . . . . . . . . . . . . .   5
     4.2.  Deploying Auto-Bandwidth Feature  . . . . . . . . . . . .   6
   5.  Extensions to the PCEP  . . . . . . . . . . . . . . . . . . .   7
     5.1.  AUTO-BANDWIDTH-ATTRIBUTE TLV  . . . . . . . . . . . . . .   7
     5.2.  BANDWIDTH Object  . . . . . . . . . . . . . . . . . . . .   9
     5.3.  The PCRpt Message . . . . . . . . . . . . . . . . . . . .   9
     5.4.  The PCInitiate Message  . . . . . . . . . . . . . . . . .   9
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   7.  Manageability Considerations  . . . . . . . . . . . . . . . .  10
     7.1.  Control of Function and Policy  . . . . . . . . . . . . .  10
     7.2.  Information and Data Models . . . . . . . . . . . . . . .  10
     7.3.  Liveness Detection and Monitoring . . . . . . . . . . . .  10
     7.4.  Verify Correct Operations . . . . . . . . . . . . . . . .  10
     7.5.  Requirements On Other Protocols . . . . . . . . . . . . .  10
     7.6.  Impact On Network Operations  . . . . . . . . . . . . . .  10
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
     8.1.  PCEP TLV Type Indicators  . . . . . . . . . . . . . . . .  11
     8.2.  AUTO-BANDWIDTH-ATTRIBUTE  . . . . . . . . . . . . . . . .  11
     8.3.  BANDWIDTH Object  . . . . . . . . . . . . . . . . . . . .  11
   9.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  11
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  12
     10.2.  Informative References . . . . . . . . . . . . . . . . .  12
   Appendix A.  Contributor Addresses  . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   [RFC5440] describes the Path Computation Element Protocol (PCEP) as
   the communication between a Path Computation Client (PCC) and a Path
   Control Element (PCE), or between PCE and PCE, enabling computation

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   of Multiprotocol Label Switching (MPLS) for Traffic Engineering Label
   Switched Path (TE LSP).

   [I-D.ietf-pce-stateful-pce] specifies extensions to PCEP to enable
   stateful control of MPLS TE LSPs.  In this document focus is on
   Active Stateful PCE where LSPs are configured on the PCC and control
   over them is delegated to the PCE.

   Over time, based on the varying traffic pattern, an LSP established
   with certain bandwidth may require to adjust the reserved bandwidth
   over time automatically.  Ingress Label Switch Router (LSR) samples
   the traffic rate at each sample-interval (BwSample) to determine the
   traffic information as Maximum Average Bandwidth (MaxAvgBw).  Further
   adjustment to the reserved bandwidth should be made at every
   adjustment-interval automatically.

   Enabling Auto-Bandwidth on a LSP results in the LSP automatically
   adjusting its bandwidth based on the actual traffic flowing through
   the LSP.  A LSP can therefore be setup with some arbitrary (or zero)
   bandwidth value such that the LSP automatically monitors the traffic
   flow and adjusts its bandwidth every adjustment-interval period.  The
   bandwidth adjustment uses the make-before-break signaling method so
   that there is no interruption to traffic flow.  This is described in
   detail in Section 4.1.  [I-D.ietf-pce-stateful-pce-app] describes the
   usecase for auto-bandwidth adjustment for passive and active stateful
   PCE.

   There are two approaches to automatic bandwidth adjustments in case
   of active stateful PCE -

   o  PCE to decide adjusted bandwidth:

      *  Active stateful PCE can use other information such as
         historical trending data, application-specific information
         about expected demands and central policy information along
         with realtime actual flow volumes to make smarter bandwidth
         adjustment to delegated LSPs.  Since LSP has delegated control
         to the PCE, it is inherently suited that it should be stateful
         PCE that decides the bandwidth adjustments.  But this requires
         PCC to report the realtime bandwidth usage as well as the
         configuration knobs etc.

   o  PCC to decide adjusted bandwidth:

      *  This approach would be similar to passive stateful PCE model,
         where the headend (PCC) monitor and calculate the new adjusted
         bandwidth and request the computed adjusted bandwidth to be
         updated.  The passive stateful PCE would use path request/reply

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         mechanism where as in active stateful PCE report/update
         mechanism is used to adjust the bandwidth.  This approach only
         require PCC to report the calculated bandwidth to be adjusted.
         But this approach does not utilize the optimization advantages
         offered by the active stateful PCE.

   This document defines extensions needed to support Auto-Bandwidth
   feature along with mechanism to provide traffic information of the
   LSPs in a stateful PCE model using PCEP.

   This document does not exclude use of any other mechanism employed by
   stateful PCE to learn real time traffic information etc.  But at the
   same time, using the same protocol (PCEP in this case) for updating
   and reporting the LSP parameters as well as to support automatic
   bandwidth adjustment is operationally beneficial.

1.1.  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 [RFC2119].

2.  Terminology

   The following terminology is used in this document.

   Active Stateful PCE:  PCE that uses tunnel state information learned
      from PCCs to optimize path computations.  Additionally, it
      actively updates tunnel parameters in those PCCs that delegated
      control over their tunnels to the PCE.

   Delegation:  :An operation to grant a PCE temporary rights to modify
      a subset of tunnel parameters on one or more PCC's tunnels.
      Tunnels are delegated from a PCC to a PCE.

   PCC:  Path Computation Client: any client application requesting a
      path computation to be performed by a Path Computation Element.

   PCE:  Path Computation Element.  An entity (component, application,
      or network node) that is capable of computing a network path or
      route based on a network graph and applying computational
      constraints.

   TE LSP:  Traffic Engineering Label Switched Path.

   Note the additional terms defined in Section 4.1.

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3.  Motivation

   An active stateful PCE can update the bandwidth for a delegated LSP
   via mechanisms described in [I-D.ietf-pce-stateful-pce].  Note that
   further extension are needed because of following reasons:

   1.  To identify the LSPs that would like to use this feature.  Not
       all LSPs in some deployments would like their bandwidth to be
       dependent on the live traffic but be constant as set by the
       operator.  Incase of PCC initiated LSP, they would be configured
       at PCC and PCEP should support a mechanism to identify the LSP
       with auto bandwidth feature enabled at the PCE.  Where as for PCE
       initiated LSP, PCEP should support mechanims to request PCC to
       provide live traffic information.

   2.  Further for LSP with auto bandwidth feature enabled, operator
       should be able to specify the knobs to control this feature like
       the bandwidth-range etc and PCEP should support their encoding.

   3.  PCC would need to report the live traffic information using the
       same protocol (PCEP in this case) making the network operations
       easier.

   Extensions as specified in this document is one of the way for PCE to
   learn this information.  But at the same time a stateful PCE MAY
   choose to learn this information from other means like management,
   performance tools.

4.  Architectural Overview

4.1.  Auto-Bandwidth Overview

   Auto-Bandwidth feature allows an LSP to automatically and dynamically
   adjust its reserved bandwidth over time, i.e. without network
   operator intervention.  The bandwidth adjustment uses the make-
   before-break adaptive signaling method so that there is no
   interruption to traffic flow.

   The new bandwidth reservation is determined by sampling the actual
   traffic flowing through the LSP.  If the traffic flowing through the
   LSP is lower than the configured or current bandwidth of the LSP, the
   extra bandwidth is being reserved needlessly and being wasted.
   Conversely, if the actual traffic flowing through the LSP is higher
   than the configured or current bandwidth of the LSP, it can
   potentially cause congestion or packet loss.  With Auto-Bandwidth
   feature, the LSP bandwidth can be set to some arbitrary value (even
   zero) during initial setup time, and it will be periodically adjusted
   over time based on the actual bandwidth requirement.

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   Note the following terms:

   Maximum Average Bandwidth (MaxAvgBw):  The maximum average bandwidth
      is the unit to measure the current traffic demand between a time
      interval.  This is the maximum value of the averaged traffic
      pattern in a particular time interval.

   Sample-Interval:  The time interval in which the traffic rate is
      collected as a sample.

   Adjustment-Interval:  The time interval in which the bandwidth
      adjustment should be made based on the MaxAvgBw.

   Minimum Bandwidth:  The minimum bandwidth that should be reserved for
      the LSP.

   Maximum Bandwidth:  The maximum bandwidth that can be reserved for
      the LSP.

   Report-Threshold:  This value indicates when the current live traffic
      bandwidth sample (BwSample) must be reported to stateful PCE via
      PCRpt message.  Only if the percentage difference between the
      current BwSample and the last BwSample is greater than or equal to
      the threshold percentage the LSP bandwidth is reported to PCE.

   Adjust-Threshold:  This value indicates when the bandwidth must be
      adjusted.  Only if the percentage difference between the current
      MaxAvgBw and the current bandwidth allocation is greater than or
      equal to the threshold percentage the LSP bandwidth is adjusted to
      the current bandwidth demand.

4.2.  Deploying Auto-Bandwidth Feature

   The traffic rate is repeatedly sampled at each sample-interval (which
   can be configured by the user and the default value as 5 minutes).
   The sampled traffic rates are accumulated over the adjustment-
   interval period (which can be configured by the user and the default
   value as 24 hours).

   The ingress LSR reports the live traffic information to the stateful
   PCE via the PCRpt message, to avoid multiple reports, the Report-
   Threshold percentage is used.  Only if the percentage difference
   between the current BwSample and the last BwSample is greater than or
   equal to the threshold percentage the LSP bandwidth is reported to
   PCE.

   Stateful PCE will adjust the bandwidth of the LSP to the highest
   sampled traffic rate amongst the set of samples taken over the

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   adjustment-interval.  Note that the highest sampled traffic rate
   could be higher or lower than the current LSP bandwidth.  Only if the
   current MaxAvgBw and the current bandwidth allocation is greater than
   or equal to the Adjust-Threshold percentage the LSP bandwidth is
   adjusted to the current bandwidth demand.

   Also to avoid multiple LSP re-signaling, sometimes operator set up
   longer adjustment intervals.  However long adjustment-interval can
   also result in an undesirable effect of masking sudden changes in
   traffic patterns.  To avoid this, the stateful PCE MAY pre-maturely
   expire the adjustment-interval to accommodate sudden bursts in
   traffic.

5.  Extensions to the PCEP

5.1.  AUTO-BANDWIDTH-ATTRIBUTE TLV

   The AUTO-BANDWIDTH-ATTRIBUTE TLV can be included as an optional TLV
   in the LSP object as described in [I-D.ietf-pce-stateful-pce].
   Whenever the LSP with Auto-Bandwidth feature enabled is delegated,
   AUTO-BANDWIDTH-ATTRIBUTE TLV is carried in PCRpt message.  The TLV
   provides PCE with the 'local configurable knobs' of this feature.  In
   case of PCE Initiated LSP ([I-D.ietf-pce-pce-initiated-lsp]) with
   this feature enabled, this TLV is included in LSP object with
   PCInitiate message.

   The format of the AUTO-BANDWIDTH-ATTRIBUTE TLV 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=[TBD]          |           Length=16           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Sample Int   |    Adj Int    | Rpt Threshold | Adj Threshold |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     Minimum Bandwidth                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     Maximum Bandwidth                         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Reserved             |           Flags             |L|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    AUTO-BANDWIDTH-ATTRIBUTE TLV format

   The type of the TLV is [TBD] and it has a fixed length of 16 octets.

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   The value contains the following fields:

   Sample Int (8 bits):  The Sample-Interval, time interval in which the
      traffic rate is collected at the PCC.

   Adj Int (8 bits):  The Adjustment-Interval, time interval in which
      the bandwidth adjustment should be made.

   Rpt Threshold (8 bits):  The Report-Threshold value is encoded in
      percentage.  Only if the percentage difference between the between
      the current BwSample and the last BwSample is greater than or
      equal to the threshold percentage the real time bandwidth sample
      is reported to PCE.

   Adj Threshold (8 bits):  The Adjust-Threshold value is encoded in
      percentage.  Only if the percentage difference between the current
      MaxAvgBw and the current bandwidth allocation is greater than or
      equal to the threshold percentage the LSP bandwidth is adjusted to
      the current bandwidth demand.

   Minimum Bandwidth (32 bits):  The minimum bandwidth allowed is
      encoded in IEEE floating point format (see [IEEE.754.1985]),
      expressed in bytes per second.  Refer to Section 3.1.2 of
      [RFC3471] for a table of commonly used values.

   Maximum Bandwidth (32 bits):  The maximum bandwidth allowed is
      encoded in IEEE floating point format (see [IEEE.754.1985]),
      expressed in bytes per second.  Refer to Section 3.1.2 of
      [RFC3471] for a table of commonly used values.

   Flags (16 bits):  One flag is currently defined:

      *  L (Live-Traffic - 1 bit): If set, PCC SHOULD report the live
         traffic information flowing on the LSP as per the Report-
         Threshold set.  Otherwise PCC only reports the calculated
         bandwidth to be adjusted to the PCE.

      Unassigned flags MUST be set to zero on transmission and MUST be
      ignored on receipt.

   Reserved (16 bits):  This field MUST be set to zero on transmission
      and MUST be ignored on receipt.

   If the above parameters are not specified by the user, based on the
   local policy at Ingress (PCC) the default value can be encoded.

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   If no default value is specified at Ingress, value 'zero' can be
   encoded for the particular field.  The stateful PCE can then apply
   its own default value based on the local policy.

5.2.  BANDWIDTH Object

   As per [RFC5440], the BANDWIDTH object is defined with two Object-
   Type values:

   o  Requested Bandwidth: BANDWIDTH Object-Type is 1.

   o  Re-optimization Bandwidth: Bandwidth of an existing TE LSP for
      which a reoptimization is requested.  BANDWIDTH Object-Type is 2.

   The new BANDWIDTH object type 3 [TBD] is used to specify the BwSample
   determined from the existing TE LSP Traffic flow at every sample-
   interval when L bit is set in AUTO-BANDWIDTH-ATTRIBUTE TLV.  The
   Report-Threshold percentage is used to determine if there is a need
   to report the current BwSample.

   If Live-Traffic (L-Bit) is not set, PCC only reports the calculated
   bandwidth to be adjusted (MaxAvgBw) to the PCE.  This is done via the
   existing 'Requested Bandwidth with BANDWIDTH Object-Type as 1'.

5.3.  The PCRpt Message

   When the delegated LSP is enabled with the Auto-Bandwidth adjustment
   feature with Live-Traffic (L-Bit) set, PCC SHOULD include the
   BANDWIDTH object of type 3 [TBD] in the PCRpt message.  The
   definition of the PCRpt message (see [I-D.ietf-pce-stateful-pce]) is
   unchanged.

   When LSP is delegated to a PCE for the very first time, BANDWIDTH
   object of type 1 is used to specify the requested bandwidth in the
   PCRpt message.  To report the live traffic flow information (as the
   BwSample) the BANDWIDTH object of type 3 [TBD] is encoded in further
   PCRpt message.

   If Live-Traffic (L-Bit) is not set, PCC SHOULD include the BANDWIDTH
   object of type 1 to specify the he calculated bandwidth to be
   adjusted to the PCE.

5.4.  The PCInitiate Message

   For PCE Initiated LSP ([I-D.ietf-pce-pce-initiated-lsp]) with Auto-
   Bandwidth feature enabled, AUTO-BANDWIDTH-ATTRIBUTE TLV is included
   in LSP object with the PCInitiate message.  The rest of the
   processing remains unchanged.

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6.  Security Considerations

   This document defines a new BANDWIDTH type and AUTO-BANDWIDTH-
   ATTRIBUTE TLV which does not add any new security concerns beyond
   those discussed in [RFC5440] and [I-D.ietf-pce-stateful-pce] in
   itself.  Some deployments may find the live traffic bandwidth
   information as extra sensitive and thus should employ suitable PCEP
   security mechanisms like TCP-AO or [I-D.ietf-pce-pceps].

7.  Manageability Considerations

7.1.  Control of Function and Policy

   The Auto-Bandwidth feature MUST BE controlled per tunnel at Ingress
   (PCC), the values for parameters like sample-interval, adjustment-
   interval, minimum-bandwidth, maximum-bandwidth, report-threshold,
   adjust-threshold, Live-Traffic (L-Bit) SHOULD BE configurable by an
   operator.

7.2.  Information and Data Models

   [RFC7420] describes the PCEP MIB, there are no new MIB Objects for
   this document.

7.3.  Liveness Detection and Monitoring

   Mechanisms defined in this document do not imply any new liveness
   detection and monitoring requirements in addition to those already
   listed in [RFC5440].

7.4.  Verify Correct Operations

   Mechanisms defined in this document do not imply any new operation
   verification requirements in addition to those already listed in
   [RFC5440].

7.5.  Requirements On Other Protocols

   Mechanisms defined in this document do not imply any new requirements
   on other protocols.

7.6.  Impact On Network Operations

   Mechanisms defined in this document do not have any impact on network
   operations in addition to those already listed in [RFC5440].

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8.  IANA Considerations

8.1.  PCEP TLV Type Indicators

   This document defines the following new PCEP TLVs; IANA is requested
   to make the following allocations from this registry.

   Value     Meaning                     Reference
   TBD       AUTO-BANDWIDTH-ATTRIBUTE    [This I.D.]

8.2.  AUTO-BANDWIDTH-ATTRIBUTE

   This document requests that a registry is created to manage the Flags
   field in the AUTO-BANDWIDTH-ATTRIBUTE TLV in the LSP object.  New
   values are to be assigned by Standards Action [RFC5226].  Each bit
   should be tracked with the following qualities:

   o  Bit number (counting from bit 0 as the most significant bit)

   o  Capability description

   o  Defining RFC

   The following values are defined in this document:

   Bit     Description            Reference
   31      Live-Traffic (L-Bit)   [This I.D.]

8.3.  BANDWIDTH Object

   This document defines new object type for the BANDWIDTH object; IANA
   is requested to make the following allocations from this registry.

   Object-Class Value   Name                               Reference
        5             BANDWIDTH                            [This I.D.]
                       Object-Type
                         3: MaxAvgBw determined from
                         the existing TE LSP Traffic
                         flow.

9.  Acknowledgments

   We would like to thank Venugopal Reddy, Reeja Paul, Sandeep Boina and
   Avantika for their useful comments and suggestions.

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10.  References

10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC5440]  Vasseur, JP. and JL. Le Roux, "Path Computation Element
              (PCE) Communication Protocol (PCEP)", RFC 5440, March
              2009.

   [I-D.ietf-pce-stateful-pce]
              Crabbe, E., Minei, I., Medved, J., and R. Varga, "PCEP
              Extensions for Stateful PCE", draft-ietf-pce-stateful-
              pce-10 (work in progress), October 2014.

   [I-D.ietf-pce-pce-initiated-lsp]
              Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "PCEP
              Extensions for PCE-initiated LSP Setup in a Stateful PCE
              Model", draft-ietf-pce-pce-initiated-lsp-02 (work in
              progress), October 2014.

10.2.  Informative References

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

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

   [RFC7420]  Koushik, A., Stephan, E., Zhao, Q., King, D., and J.
              Hardwick, "Path Computation Element Communication Protocol
              (PCEP) Management Information Base (MIB) Module", RFC
              7420, December 2014.

   [I-D.ietf-pce-stateful-pce-app]
              Zhang, X. and I. Minei, "Applicability of a Stateful Path
              Computation Element (PCE)", draft-ietf-pce-stateful-pce-
              app-03 (work in progress), October 2014.

   [I-D.ietf-pce-pceps]
              Lopez, D., Dios, O., Wu, W., and D. Dhody, "Secure
              Transport for PCEP", draft-ietf-pce-pceps-03 (work in
              progress), March 2015.

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   [IEEE.754.1985]
              Institute of Electrical and Electronics Engineers,
              "Standard for Binary Floating-Point Arithmetic", IEEE
              Standard 754, August 1985.

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Appendix A.  Contributor Addresses

   He Zekun
   Tencent Holdings Ltd,
   Shenzhen P.R.China

   Email: kinghe@tencent.com

   Xian Zhang
   Huawei Technologies
   Research Area F3-1B,
   Huawei Industrial Base,
   Shenzhen, 518129, China

   Phone: +86-755-28972645
   Email: zhang.xian@huawei.com

   Young Lee
   Huawei Technologies
   1700 Alma Drive, Suite 100
   Plano, TX  75075
   US

   Phone: +1 972 509 5599 x2240
   Fax:   +1 469 229 5397
   EMail: leeyoung@huawei.com

Authors' Addresses

   Dhruv Dhody
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560037
   India

   EMail: dhruv.ietf@gmail.com

   Udayasree Palle
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560037
   India

   EMail: udayasree.palle@huawei.com

Dhody, et al.           Expires September 6, 2015              [Page 14]
Internet-Draft                   AUTO-BW                      March 2015

   Ravi Singh
   Juniper Networks
   1194 N. Mathilda Ave.
   Sunnyvale, CA  94089
   USA

   EMail: ravis@juniper.net

Dhody, et al.           Expires September 6, 2015              [Page 15]