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PCE Working Group                                              R. Gandhi
Internet-Draft                                       Cisco Systems, Inc.
Intended Status: Standards Track                                  B. Wen
Expires: March 2, 2018                                           Comcast
                                                                C. Barth
                                                        Juniper Networks
                                                                D. Dhody
                                                     Huawei Technologies
                                                         August 29, 2017

        PCEP Extensions for MPLS-TE LSP Performance Measurements
                             with Stateful PCE
                          draft-gandhi-pce-pm-08


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 allow Stateful control of Multi-Protocol
   Label Switching (MPLS) Traffic Engineering Label Switched Paths (TE
   LSPs) using PCEP.

   In certain networks, network performance data such as packet loss,
   delay and delay variation (jitter) as well as bandwidth utilization
   is a critical measure for Traffic Engineering (TE).  This data
   provides operators the characteristics of their networks for
   performance evaluation that is required to ensure the Service Level
   Agreements (SLAs).  Performance Measurement (PM) mechanisms can be
   employed to monitor these metrics end-to-end for TE Label Switched
   Paths (LSPs).  This document describes Path Computation Element
   Protocol (PCEP) extensions for enabling and reporting such
   performance measurements to an Active Stateful PCE for both PCE-
   Initiated and PCC-Initiated LSPs.


Status of this Memo

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

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   Internet-Drafts are draft documents valid for a maximum of six months



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   and may be updated, replaced, or obsoleted by other documents at any
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   Copyright (c) 2017 IETF Trust and the persons identified as the
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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
     1.1.  Use-cases  . . . . . . . . . . . . . . . . . . . . . . . .  6
     1.2.  Dependencies and Considerations  . . . . . . . . . . . . .  8
     1.3.  Auto-bandwidth Considerations  . . . . . . . . . . . . . .  9
   2.  Conventions Used in This Document  . . . . . . . . . . . . . .  9
     2.1.  Requirements Language  . . . . . . . . . . . . . . . . . .  9
     2.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  9
     2.3.  Measurement Units  . . . . . . . . . . . . . . . . . . . . 10
   3.  Overview of the PCEP Extensions  . . . . . . . . . . . . . . . 10
     3.1.  Report Thresholds  . . . . . . . . . . . . . . . . . . . . 11
   4.  Sub-TLVs for Measurements Attributes . . . . . . . . . . . . . 12
     4.1.  Measurement-Enable sub-TLV . . . . . . . . . . . . . . . . 12
     4.2.  Measurement-Interval sub-TLV . . . . . . . . . . . . . . . 13
     4.3.  Report-Threshold sub-TLV . . . . . . . . . . . . . . . . . 13
     4.4.  Report-Threshold-Percentage sub-TLV  . . . . . . . . . . . 14
     4.5.  Report-Interval sub-TLV  . . . . . . . . . . . . . . . . . 14
     4.6.  Report-Upper-Bound sub-TLV . . . . . . . . . . . . . . . . 15
   5.  PCEP Extensions for Reporting Delay Measurement  . . . . . . . 16
     5.1.  Delay Measurement Capability Advertisement . . . . . . . . 16
       5.1.1.  DELAY-MEASUREMENT-CAPABILITY TLV . . . . . . . . . . . 16
     5.2.  DELAY-MEASUREMENT-ATTRIBUTES TLV . . . . . . . . . . . . . 17
       5.2.1.  Delay Measurement Enable . . . . . . . . . . . . . . . 18
       5.2.2.  Delay Measurement Interval . . . . . . . . . . . . . . 18
       5.2.3.  Delay Measurement Report Threshold . . . . . . . . . . 18
       5.2.4.  Delay Measurement Report Threshold Percentage  . . . . 18
       5.2.5.  Delay Measurement Report Interval  . . . . . . . . . . 19
       5.2.6.  Delay Measurement Upper Bound  . . . . . . . . . . . . 19
     5.3.  DELAY-MEASUREMENT Object . . . . . . . . . . . . . . . . . 19
   6.  PCEP Extensions for Reporting Loss Measurement . . . . . . . . 21
     6.1.  Loss Measurement Capability Advertisement  . . . . . . . . 21
       6.1.1.  LOSS-MEASUREMENT-CAPABILITY TLV  . . . . . . . . . . . 22
     6.2.  LOSS-MEASUREMENT-ATTRIBUTES TLV  . . . . . . . . . . . . . 23
       6.2.1.  Loss Measurement Enable  . . . . . . . . . . . . . . . 24
       6.2.2.  Loss Measurement Interval  . . . . . . . . . . . . . . 24
       6.2.3.  Loss Measurement Report Threshold  . . . . . . . . . . 24
       6.2.4.  Loss Measurement Report Threshold Percentage . . . . . 24
       6.2.5.  Loss Measurement Report Interval . . . . . . . . . . . 25
       6.2.6.  Loss Measurement Upper Bound . . . . . . . . . . . . . 25
     6.3.  LOSS-MEASUREMENT Object  . . . . . . . . . . . . . . . . . 25
   7.  PCEP Extensions for Reporting Bandwidth Utilization  . . . . . 26
     7.1.  Bandwidth Utilization Capability Advertisement . . . . . . 26
       7.1.1.  BANDWIDTH-UTILIZATION-CAPABILITY TLV . . . . . . . . . 27
     7.2.  BW-UTILIZATION-MEASUREMENT-ATTRIBUTES TLV  . . . . . . . . 27
       7.2.1.  Bandwidth Utilization Measurement Enable . . . . . . . 28
       7.2.2.  Bandwidth Utilization Measurement Interval . . . . . . 28
       7.2.3.  Bandwidth Utilization Report Threshold . . . . . . . . 28



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       7.2.4.  Bandwidth Utilization Report Threshold Percentage  . . 28
       7.2.5.  Bandwidth Utilization Report Interval  . . . . . . . . 29
       7.2.6.  Bandwidth Utilization Upper Bound  . . . . . . . . . . 29
     7.3.  BANDWIDTH Object . . . . . . . . . . . . . . . . . . . . . 29
   8.  PCEP Procedure . . . . . . . . . . . . . . . . . . . . . . . . 29
     8.1.  Various MEASUREMENT-ATTRIBUTES TLVs  . . . . . . . . . . . 30
     8.2.  The MEASUREMENT Objects  . . . . . . . . . . . . . . . . . 30
   9.  Scaling Considerations . . . . . . . . . . . . . . . . . . . . 30
     9.1.  The PCNtf Message  . . . . . . . . . . . . . . . . . . . . 31
   10.  Security Considerations . . . . . . . . . . . . . . . . . . . 31
   11.  Manageability Considerations  . . . . . . . . . . . . . . . . 31
     11.1.  Control of Function and Policy  . . . . . . . . . . . . . 32
     11.2.  Information and Data Models . . . . . . . . . . . . . . . 32
     11.3.  Liveness Detection and Monitoring . . . . . . . . . . . . 32
     11.4.  Verify Correct Operations . . . . . . . . . . . . . . . . 32
     11.5.  Requirements On Other Protocols . . . . . . . . . . . . . 32
     11.6.  Impact On Network Operations  . . . . . . . . . . . . . . 32
   12.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . 32
     12.1.  Measurement Capability TLV Types  . . . . . . . . . . . . 33
       12.1.1.  Flag Fields for MEASUREMENT-CAPABILITY TLVs . . . . . 33
     12.2.  MEASUREMENT-ATTRIBUTES TLVs . . . . . . . . . . . . . . . 34
       12.2.1.  The Sub-TLVs For MEASUREMENT-ATTRIBUTES TLVs  . . . . 34
         12.2.1.1.  Flag Fields in Measurement-Enable sub-TLV . . . . 34
     12.3.  Measurement Object-Class  . . . . . . . . . . . . . . . . 35
       12.3.1.  DELAY-MEASUREMENT Object-Types  . . . . . . . . . . . 35
       12.3.2.  LOSS-MEASUREMENT Object-Types . . . . . . . . . . . . 35
       12.3.3.  BANDWIDTH Object-Type . . . . . . . . . . . . . . . . 36
     12.4.  PCE Error Codes . . . . . . . . . . . . . . . . . . . . . 36
     12.5.  Notification Object-Type  . . . . . . . . . . . . . . . . 36
   13.  References  . . . . . . . . . . . . . . . . . . . . . . . . . 38
     13.1.  Normative References  . . . . . . . . . . . . . . . . . . 38
     13.2.  Informative References  . . . . . . . . . . . . . . . . . 38
   Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . . . 40
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 40

















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1.  Introduction

   [RFC5440] describes the Path Computation Element Protocol (PCEP) as a
   communication mechanism between a Path Computation Client (PCC) and a
   Path Control Element (PCE), or between PCE and PCE, that enables
   computation of Multi-Protocol Label Switching (MPLS) Traffic
   Engineering Label Switched Paths (TE LSPs).

   [DRAFT-PCE-STATEFUL] specifies extensions to PCEP to enable Stateful
   control of TE LSPs.  It describes two mode of operations - Passive
   Stateful PCE and Active Stateful PCE.  Further [DRAFT-PCE-INITIATED-
   LSP] describes the setup, maintenance and teardown of PCE-Initiated
   LSPs for the Stateful PCE model.  In this document, the focus is on
   Active Stateful PCE where the LSPs are controlled by the PCE, for
   both PCE-Initiated and PCC-Initiated LSPs.

   In certain networks, such as financial information networks, network
   performance data (e.g. packet loss, delay and delay variation
   (jitter), bandwidth utilization) is a critical measure for traffic
   engineering.  The protocol extensions have been defined to advertise
   link performance metrics, see [RFC7471], [RFC7810], [RFC7823] and
   [DRAFT-IDR-TE-PM-BGP].  This data provides operators the
   characteristics of their networks for performance evaluation that is
   required to ensure the Service Level Agreements (SLAs).

   [DRAFT-PCE-SERVICE-AWARE] defines the PCEP extensions for TE LSP path
   computation using packet loss, delay and delay variation as path
   selection metrics.  Such path computations use link metrics for
   packet loss and delay and do not provide end-to-end metrics of the TE
   LSPs.  The end-to-end metrics of a TE LSP may be very different than
   the path computation results due to many factors, such as queuing,
   etc.  There is a need to verify and monitor that the traffic sent
   over the established TE LSPs does not exceed the requested metric
   bounds (e.g. total end-to-end delay/loss).  The Stateful PCE may need
   to take some action (such as tear-down or re-optimize the LSP) when
   the performance requirement is not met.  [RFC6374], [RFC6375] and
   [RFC7876] define protocol extensions needed for measuring end-to-end
   packet loss, delay and delay variation (jitter) for bidirectional and
   unidirectional TE LSPs.

   This document provides mechanisms to enable and report the
   performance measurements (PM) such as packet loss, delay, delay
   variation (jitter) and bandwidth utilization for a TE LSP to an
   Active Stateful PCE, for both PCE-Initiated and PCC-Initiated LSPs.







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1.1.  Use-cases

   This section describes a non-exhaustive list of deployment use-cases
   of PM for TE LSPs when deployed in a network with PCE.  A controller
   may also be deployed in the network capable of "streaming telemetry"
   for receiving PM metrics and may interact with PCC and PCE for the PM
   as described in use-cases 3, 4 and 5.

   Use-case 1: PCE Enables PM on PCC and PCC Takes Action

   PCE -----> PCC

   In this use-case, the PCE sets the upper-bound threshold condition
   for TE LSPs at the PCC.  The PCC takes a local action when the
   condition is met.  The action could be based on a local policy or
   policy set by the PCE.  The steps involved are -

   o  PCE sends the PM attributes as part of PCE-initiated LSPs
      including upper-bound threshold (Section 4.6 in this document) for
      the PM metrics using the PCEP extensions defined in this document.

   o  PCC takes actions when PM metrics exceed the upper-bound
      threshold, actions could be to bring down the LSP, trigger
      protection switchover, remove tunnel from IGP for some prefixes,
      or request a new path from PCE (based on local policies which may
      be set by the PCE).  PCC may take these actions even when LSPs are
      delegated to PCE as the upper-bound is set by the PCE.

   o  PCC does not report the PM metrics to PCE.

   o  PCC may install the new LSP in routing table only if the PM metric
      is below the upper-bound, otherwise, the PCC may reject the LSP
      request and send an error to the PCE.

   o  The report interval should be set to 0 to disable reporting to
      PCE.  Only the upper-bound threshold should be set.

   Use-case 2: PCC Reports PM Metrics to PCE, PCE Takes Action

   PCE <----- PCC

   In this use-case, the PCC reports the PM metrics and parameters to
   the PCE and the PCE may take an immediate local (reactive) action
   based on the PM metrics.  The steps involved are -

   o  PCC sends the PM metrics and parameters to PCE using the PCEP
      extensions defined in this document and PCE takes an action;
      action could be to correlate faults, invalidate LSP path, send new



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      LSP path to PCC (trigger re-optimization), etc.

   o  If upper-bound threshold is set, PCC only reports the PM metrics
      to PCE when upper-bound is crossed.  Otherwise the PCC reports the
      PM metrics to PCE every report-interval.

   o  Optionally, PCC may take an immediate local (reactive) action such
      as trigger path protection switch-over when PM metrics exceed
      upper-bound.

   o  PCE has a global view due to PM metric reports received from
      various PCCs and hence can make a better decision about LSP
      placement in the network.

   o  PCE can make pro-active decisions based on PM metrics when metrics
      are reported before crossing of the upper-bound as opposed to
      reactive action that PCC could make.

   o  The report interval should be set to enable reporting by the PCC.
      Optionally, the upper-bound threshold may also be set.

   Use-case 3: PCE Enables PM on PCC, PCC Sends PM Metrics to Controller

   PCE -----> PCC -----> Controller

   The steps involved are -

   o  A controller may be used in a network that is capable of
      "streaming telemetry" for receiving data and Yang or XML based
      provisioning using non-PCEP channel.  The controller may interact
      with a PCE for LSP path computation using the PCEP channel.

   o  PCE sends the PM attributes as part of PCE-initiated LSPs using
      the PCEP extensions defined in this document.

   o  PCC reports the PM metrics to controller via "streaming
      telemetry".

   o  Controller may request PCE to take an action based on the PM
      metrics.

   o  The report interval should be set to  0 to disable reporting to
      PCE.  The other PM attributes may be set and used for "streaming
      telemetry".

   Use-case 4: Controller Enables PM on PCC, PCC Sends PM Metrics to PCE

   PCE <----- PCC <----- Controller



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   The steps involved are -

   o  Controller enables PM on PCC using a non-PCEP channel.

   o  PCC then reports the PM metrics to PCE using the PCEP extensions
      defined in this document.

   o  PCE may take an action based on the PM metrics received from PCC.


   Use-case 5: Controller Enables PM on PCC, PCC Sends PM Metrics to
   Controller

   PCE ----> PCC <-----> Controller -----> PCE

   The steps involved are -

   o  Controller enables PM on PCC using a non-PCEP channel.

   o  PCC reports the PM metrics to the controller via "streaming
      telemetry".

   o  Controller may request PCE to take an action based on the PM
      metrics.

   o  The PCEP extensions defined in this document are not used in this
      use-case.


1.2.  Dependencies and Considerations

   [RFC6374] describes several reasons why PMs are valuable to
   operators.  Note that the specification of the use of the reported
   packet loss, delay, delay variation and bandwidth utilization
   measurements by a Stateful PCE is outside the scope of this document.

   Furthermore, [RFC6374] describes many types of MPLS channels that may
   leverage PMs and some may have bidirectional dependencies.  Defining
   a mechanism for the verification and/or provisioning of bidirectional
   or associated bidirectional LSPs within the Stateful PCE architecture
   is outside the scope of this document.

   In all cases, delay and loss PM messages are carried over the MPLS
   Generic Associated Channel (G-ACh) as described in [RFC5586].  MPLS
   LSPs that carry the G-ACh can be referred to as MPLS Transport
   Profile (MPLS-TP) LSPs [RFC5921].  MPLS-TP LSPs require Ultimate Hop
   Popping (UHP) where LSPs are assigned Non-NULL labels by tail-end
   nodes.  It is beyond the scope of this document to define the



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   mechanism by which a Stateful PCE verifies and/or provisions an LSP
   for UHP.  Note that for both unidirectional and bidirectional LSPs,
   packet loss measurement requires UHP.

1.3.  Auto-bandwidth Considerations

   Auto-Bandwidth feature allows a head-end LSR (PCC) to automatically
   adjust the LSP bandwidth reservation based on the traffic demand of a
   TE LSP.  Auto-bandwidth requested bandwidth computation can be
   implemented on a PCC or a Stateful PCE.

   [DRAFT-IETF-PCE-AUTOBW] describes the PCEP extensions for auto-
   bandwidth, where the requested bandwidth for the LSP is computed by
   the PCC and reported to the Stateful PCE.  There is a benefit in
   pushing the responsibility for deciding when auto-bandwidth
   adjustments are needed to the PCC as this distributes the load of
   monitoring the bandwidth utilization of the LSPs down to the PCCs and
   frees up the PCE for path computations.  In addition, it reduces the
   load on PCEP communications for reporting the bandwidth utilization
   of the LSP.

   However, exactly when to adjust an LSP bandwidth could be better left
   to a Stateful PCE.  That is, a PCE could be flexible in its
   interpretation of thresholds enabling it to trigger auto-bandwidth
   adjustment early if it believes there is a good reason (for example,
   doing a set of parallel path re-computations) or late (for example,
   when it knows that an adjustment would be disruptive to the network).
    When the auto-bandwidth computation is delegated to the PCC, the PCC
   cannot see the impact on other LSPs in the network, and the PCE
   cannot tell whether the request to adjust the LSP bandwidth is
   critical or not.  The bandwidth utilization reporting defined in this
   document can be used by the PCE to do computations to determine
   whether auto-bandwidth adjustments are needed and/or desirable before
   performing the path computations.


2.  Conventions Used in This Document

2.1.  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].

2.2.  Terminology

   The reader is assumed to be familiar with the terminology defined in
   [RFC5440], [RFC6374] and [RFC7471].



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2.3.  Measurement Units

   The measurement unit for delay value is defined in [RFC7471], Section
   4.1.5.

   The measurement unit for loss value is defined in [RFC7471], Section
   4.4.5.

   The utilized bandwidth [RFC7471] is encoded in IEEE floating point
   format in bytes per second (see [IEEE.754.1985]).

   All average values are calculated as rolling averages.


3.  Overview of the PCEP Extensions

   The high-level overview of the PCEP extensions defined in this
   document for requesting and reporting end-to-end performance
   measurements and bandwidth utilization for TE LSPs are shown in
   Figure 1.

                           ---------
                          |         |
                          |   PCE   |
                          |         |
                           ---------
                             |    ^
     MEASUREMENT CAPABILITY  |    |  MEASUREMENT CAPABILITY
                             |    |
     MEASUREMENT ATTRIBUTES  |    |  MEASUREMENT ATTRIBUTES
                             |    |  (For delegated LSPs)
                             |    |
                             |    |  MEASUREMENT REPORTS
                             v    |
                           ---------
                          |         |
                          |   PCC   |
                          |         |
                           ---------

              Figure 1: Overview of PCEP Extensions

   The following steps describe the PCEP extensions for reporting
   performance measurements and bandwidth utilization of TE LSPs:

   o  The Stateful PCE and PCC (head-end of the LSP) advertise the
      capability of their support for the delay, loss and bandwidth-
      utilization measurements and reporting in the PCEP Open message



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      (in the OPEN Object).

   o  The Stateful PCE enables the measurement of a feature and sends
      and updates the configuration parameters of the feature using the
      LSPA object to PCC in PCInitiate and PCUpd messages respectively.

   o  The PCC reports the measured values of the feature to the Stateful
      PCE at the end of the specified report-interval or when measured
      values cross the specified report-threshold.  The periodic
      reporting can be used at the PCE to monitor the TE LSP metrics
      whereas report-threshold can be used to trigger an immediate
      action at the PCE on the TE LSP.

   o  In some cases, the periodic reporting of the measurements may be
      disabled and only an upper-bound threshold is set, which when
      exceeded, a local or PCE-set action may be taken.

   o  The PCE and PCC notify each other of their entering and clearing
      the overwhelmed state when operating under high LSP scale.


3.1.  Report Thresholds

   When explicitly configured, report threshold (absolute or percentage)
   parameter (along with the configured number of counts) is used to
   trigger an immediate reporting of the delay and loss measurements and
   bandwidth utilization, bypassing the report interval.  Threshold is
   used to detect a sudden change in the performance measurement metric
   of a TE LSP.  In order to detect that a measured value has crossed
   the threshold, the measured (delay/loss) metric is compared with the
   last reported value.  If the change (increase or decrease) in the
   value is above the threshold (absolute or percentage) consecutively
   for the given number of counts, the measurement from the current
   interval is reported immediately.  In case of bandwidth utilization,
   the last reported MaxSampleBw (see [DRAFT-IETF-PCE-AUTOBW]) value is
   compared with the MaxSampleBW from the the current interval to detect
   the threshold crossing.  The delay and loss measurements are still
   reported at the end of the report interval even if they were reported
   due to the crossing of the threshold.  Refer to [RFC7471], Section 5,
   for additional considerations.

   All thresholds in this document could be represented in both absolute
   value and percentage, and could be used together.  This is provided
   to accommodate the cases where the metric values may become very
   large or very small over time.  For example, an operator may use the
   percentage threshold to handle small to large metric values and
   absolute values to handle very large metric values.  The metrics are
   reported when either one of the two thresholds, the absolute or



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   percentage, is crossed.

   When using the percentage threshold, if the metric changes rapidly at
   very low values, it may trigger frequent reporting due to the
   crossing of the percentage threshold.  This can lead to unnecessary
   scale issues in the network.  This is suppressed by setting the
   minimum-threshold parameter along with the percentage threshold.  The
   metric value is only reported if the value crosses both the
   percentage threshold and the minimum-threshold parameters.

4.  Sub-TLVs for Measurements Attributes

   This section specifies the generic sub-TLVs those provide various
   configurable parameters for reporting measurements to a Stateful PCE.
    These sub-TLVs are carried in various measurement attributes TLVs
   defined in this document.

   Following sub-TLVs are defined:

   Type Len  Name
   -----------------------------------------------------------------
    1   4    Measurement-Enable sub-TLV
    2   4    Measurement-Interval sub-TLV
    3   8    Report-Threshold sub-TLV
    4   8    Report-Threshold-Percentage sub-TLV
    5   4    Report-Interval sub-TLV
    6   8    Report-Upper-Bound sub-TLV

   The Measurement-Enable sub-TLV MUST be added in the LSPA Object when
   the measurement feature is enabled for the LSP.  All other sub-TLVs
   are optional and any unrecognized sub-TLV MUST be silently ignored.
   If a sub-TLV of same type appears more than once, only the first
   occurrence is processed and all others MUST be ignored.  If sub-TLVs
   are not present, the default values based on the local policy are
   assumed.

4.1.  Measurement-Enable sub-TLV

   The Measurement-Enable sub-TLV specifies that the given measurement
   feature is enabled.

    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=1              |           Length=4            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Flags                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



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                  Measurement-Enable sub-TLV Format

   The Type is 1, Length is 4 bytes, and the value comprises of flags
   (32 bits) for enabling various measurement features.

   Unassigned flags are considered reserved, they MUST be set to 0 when
   sent and MUST be ignored when received.

4.2.  Measurement-Interval sub-TLV

   The Measurement-Interval sub-TLV specifies a time interval in seconds
   for the measurement.

    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=2              |           Length=4            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Measurement-Interval                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Measurement-Interval sub-TLV Format

   The Type is 2, Length is 4 bytes, and the value comprises of 4-byte
   time interval, the valid range is from 1 to 604800, in seconds.  The
   default value is 300 seconds.  The Measurement-Interval MUST NOT be
   greater than Report-Interval.

4.3.  Report-Threshold sub-TLV

   The Report-Threshold sub-TLV specifies the threshold value used to
   trigger an immediate reporting of the measurements bypassing the
   report-interval.

    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=3              |           Length=8            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         RESERVED                              |      Count    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Report-Threshold                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Report-Threshold sub-TLV Format

   The Type is 3, Length is 8 bytes, and the value comprises of -




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   o  Report-Threshold:  32-bit absolute threshold value.

   o  Count: 8-bit integer counter.  The number of consecutive
      measurement values MUST be above the threshold before reporting
      the measurement.  The value 0 is considered to be invalid.  By
      default, report-threshold is not set and threshold check based
      reporting is disabled.

   o  RESERVED: It MUST be set to zero when sent and MUST be ignored
      when received.

4.4.  Report-Threshold-Percentage sub-TLV

   The Report-Threshold-Percentage sub-TLV specifies the threshold value
   used to trigger an immediate reporting of the measurements bypassing
   the report-interval.

    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=4              |           Length=8            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Percentage |          RESERVED               |     Count     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Minimum-Threshold                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Report-Threshold-Percentage sub-TLV Format

   The Type is 4, Length is 8 bytes, and the value comprises of -

   o  Percentage: 7-bit threshold value, encoded in percentage (an
      integer from 1 to 100).

   o  Count: 8-bit integer counter.  The number of consecutive
      measurement values MUST be above threshold before reporting the
      measurement.  The value 0 is considered to be invalid.  By
      default, report-threshold-percentage is not set and threshold
      check based reporting is disabled.

   o  RESERVED: It MUST be set to zero when sent and MUST be ignored
      when received.

   o  Minimum-Threshold: The 32-bit absolute Minimum-Threshold value.
      The increase or decrease should be at least or above this value.

4.5.  Report-Interval sub-TLV




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   The Report-Interval sub-TLV specifies the time interval in seconds
   when measured values are to be reported.

    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=5              |           Length=4            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Report-Interval                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Report-Interval sub-TLV Format

   The Type is 5, Length is 4 bytes, and the value comprises of 4-byte
   time interval, the valid range is from 0 to 604800, in seconds.  The
   default value is 3600 seconds.  The value 0 is used to disable the
   periodic reporting of the measurements.

4.6.  Report-Upper-Bound sub-TLV

   The Report-Upper-Bound sub-TLV specifies the upper-bound value used
   to trigger an immediate reporting of the measurements when crossed.
   This may also result in PCC taking an immediate local action on the
   LSP.

    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=6              |           Length=8            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         RESERVED                              |      Count    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Report-Upper-Bound                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Report-Upper-Bound sub-TLV Format

   The Type is 6, Length is 8 bytes, and the value comprises of -

   o  Report-Upper-Bound:  32-bit absolute value.

   o  Count: 8-bit integer counter.  The number of consecutive
      measurement values MUST be above the upper-bound before reporting
      the measurement.  The value 0 is considered to be invalid.  By
      default, upper-bound is not set.

   o  RESERVED: It MUST be set to zero when sent and MUST be ignored
      when received.



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5.  PCEP Extensions for Reporting Delay Measurement

5.1.  Delay Measurement Capability Advertisement

   During PCEP Initialization Phase, PCEP Speakers (PCE or PCC)
   advertise their support of DELAY-MEASUREMENT.  A PCEP Speaker (PCE or
   PCC) includes the DELAY-MEASUREMENT-CAPABILITY TLV, in the OPEN
   Object to advertise its support for PCEP Delay-Measurement
   extensions.  The presence of the DELAY-MEASUREMENT-CAPABILITY TLV in
   the OPEN Object (in the Open message) indicates that the Delay
   Measurement capability is supported as described in this document.
   Additional procedure is defined as following:

   o  The PCEP protocol extensions for Delay Measurement MUST NOT be
      used if one or both PCEP Speakers have not included the DELAY-
      MEASUREMENT-CAPABILITY TLV in their respective Open message.

   o  If the PCEP speaker that supports the extensions of this document
      but did not advertise this capability, then upon receipt of DELAY-
      MEASUREMENT-ATTRIBUTES TLV in LSPA object, it SHOULD generate a
      PCErr with error-type 19 (Invalid Operation), error-value TBD7
      (Delay-Measurement capability was not advertised) and it will
      terminate the PCEP session.

   o  Similarly, the PCEP speaker SHOULD generate error-value TBD9
      (Bidirectional Measurement capability was not advertised) and
      TBD10 (Unidirectional Measurement capability was not advertised)
      upon receipt of DELAY-MEASUREMENT-ATTRIBUTES TLV in LSPA object
      with two-way measurement request and one-way measurement request,
      respectively, when it did not advertise this capability.

   o  If the PCEP speaker that supports the extensions of this document
      but did not advertise this capability, then upon receipt of DELAY-
      MEASUREMENT object, it SHOULD generate a PCErr with error-type 19
      (Invalid Operation), error-value TBD7 (Delay-Measurement
      capability was not advertised) and it will terminate the PCEP
      session.

5.1.1.  DELAY-MEASUREMENT-CAPABILITY TLV

   The DELAY-MEASUREMENT-CAPABILITY TLV is an optional TLV for use in
   the OPEN Object for Delay Measurement via PCEP capability
   advertisement.  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=TBD1       |           Length=4            |



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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Flags                         |T|O|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  DELAY-MEASUREMENT-CAPABILITY TLV Format

   The Type of the TLV is TBD1 and it has a fixed length of 4 bytes.

   The value comprises a single field - Flags (32 bits):

   o  O (One-way Delay Measurement - 1 bit): if set to 1 by a PCC, the O
      Flag indicates that the PCC allows reporting of one-way delay
      measurement information; if set to 1 by a PCE, the O Flag
      indicates that the PCE is capable of receiving one-way delay
      measurement information from the PCC.

   o  T (Two-way Delay Measurement - 1 bit): if set to 1 by a PCC, the T
      Flag indicates that the PCC allows reporting of two-way delay
      measurement information; if set to 1 by a PCE, the T Flag
      indicates that the PCE is capable of receiving two-way delay
      measurement information from the PCC.  Two-way measurement is only
      applicable to the bidirectional LSPs (e.g. MPLS-TP LSPs
      [RFC5921]).

   Unassigned bits are considered reserved.  They MUST be set to 0 when
   sent and MUST be ignored when received.

   Advertisement of the DELAY-MEASUREMENT-CAPABILITY TLV implies support
   of delay measurement, as well as the objects, TLVs and procedures
   defined in this document.  Either O or T flag MUST be set in the TLV.

5.2.  DELAY-MEASUREMENT-ATTRIBUTES TLV

   The DELAY-MEASUREMENT-ATTRIBUTES TLV provides the configurable
   parameters of the delay measurement feature.

   The format of the DELAY-MEASUREMENT-ATTRIBUTES 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |       PCEP TLV Type TBD4      |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   //                           sub-TLVs                          //
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



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                  DELAY-MEASUREMENT-ATTRIBUTES TLV Format

   PCEP TLV Type is defined as following:

    Type      Name
    ----------------------------------------------------------
     TBD4     DELAY-MEASUREMENT-ATTRIBUTES

   Length: The Length field defines the length of the value portion in
   bytes as per [RFC5440].

   Value: Comprises of one or more sub-TLVs as described in Section 4 of
   this document.

   The following sub-sections describe the parameters which are
   currently defined to be carried within this TLV.

5.2.1.  Delay Measurement Enable

   The Measurement-Enable sub-TLV specifies the delay measurement mode
   enabled using following flags:

   Bit     Description
   ------------------------------------------------------------------
    31     One-Way Delay Measurement Enabled
    30     Two-Way Delay Measurement Enabled

5.2.2.  Delay Measurement Interval

   The Measurement-Interval sub-TLV specifies a time interval in seconds
   for the delay measurement.

5.2.3.  Delay Measurement Report Threshold

   The Report-Threshold sub-TLV specifies the threshold value used to
   trigger an immediate reporting of the delay measurements bypassing
   the report-interval.

   o  Report-Threshold: Delay in microseconds, encoded as 24-bit
      integer, as defined in [RFC7471].

   Same report-threshold is used for all delay measurement values.

5.2.4.  Delay Measurement Report Threshold Percentage

   The Report-Threshold-Percentage sub-TLV specifies the threshold value
   used to trigger an immediate reporting of the measurements bypassing
   the report-interval.



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   Same report-threshold-percentage is used for all delay measurement
   values.

5.2.5.  Delay Measurement Report Interval

   The Report-Interval sub-TLV specifies the time interval in seconds
   when measured delay values are to be reported.

5.2.6.  Delay Measurement Upper Bound

   The Report-Upper-Bound sub-TLV specifies the upper-bound value in
   microseconds, and is used to trigger an immediate reporting of the
   delay values when crossed.  This may also result in PCC taking an
   immediate local action on the LSP.


5.3.  DELAY-MEASUREMENT Object

   A new object, DELAY-MEASUREMENT with Object-Class (Value TBD5) is
   defined in this document to report the delay measurement of a TE LSP.

   When the LSP is enabled with the delay measurement feature, the PCC
   SHOULD include the DELAY-MEASUREMENT Object to report the measured
   delay values to the PCE in the PCRpt message.  The PCC SHOULD report
   (either one-way or two-way) average delay, min/max delay and delay
   variations to the PCE in the PCRpt message.


     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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Class=TBD5    |   OT  |Res|P|I|   Object Length (bytes)       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   //                        (Object body)                        //
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    DELAY-MEASUREMENT Object Format

   Object Length (16 bits):  Specifies the total object length including
        the header, in bytes as per [RFC5440].

   Object-Types (OT) are defined as follows:

   Object-Type  Len   Name
   --------------------------------------------------------------
    1           8     One-Way Delay Measurement Value



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    2           12    One-Way Delay Measurement Min/Max Values
    3           8     One-Way Delay Variation Measurement Value
    4           8     Two-Way Delay Measurement Value
    5           12    Two-Way Delay Measurement Min/Max Values
    6           8     Two-Way Delay Variation Measurement Value


   The object body formats are defined as following:

   For Object-Types 1 and 4:

     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  |            Delay Value Average                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   For Object-Types 2 and 5:

     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  |            Delay Value Minimum                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     RESERVED  |            Delay Value Maximum                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   For Object-Types 3 and 6:

     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  |            Delay Variation Value              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      DELAY-MEASUREMENT Object Body Formats (One-Way and Two-Way)


   Al delay values are reported in microseconds, encoded as 24-bit
   integer, as defined in [RFC7471].  When set to the maximum value
   16,777,215 (16.777215 sec), the delay is at least that value and may
   be larger.

   o  One-way Delay Measurement Value: Average Delay of the LSP in one
      (forward) direction.




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   o  One-way Delay Measurement Variation Value: Average Delay Variation
      of the LSP in one (forward) direction.

   o  One-Way Delay Measurement Value Minimum/Maximum: Minimum and
      Maximum values of the Delay of the LSP in one (forward) direction
      in the last measurement interval.

   o  Two-way Delay Measurement Value: Average Delay of the
      bidirectional LSP in both (forward and reverse) directions.

   o  Two-way Delay Measurement Variation Value: Average Delay Variation
      of the bidirectional LSP in both (forward and reverse)
      directions.

   o  Two-Way Delay Measurement Value Minimum/Maximum: Minimum and
      Maximum values of the Delay of the bidirectional LSP in both
      (forward and reverse) directions in the last measurement interval.

   o  RESERVED: This field is reserved for future use.  It MUST be set
      to 0 when sent and MUST be ignored when received.


6.  PCEP Extensions for Reporting Loss Measurement

6.1.  Loss Measurement Capability Advertisement

   During PCEP Initialization Phase, PCEP Speakers (PCE or PCC)
   advertise their support of LOSS-MEASUREMENT.  A PCEP Speaker includes
   the LOSS-MEASUREMENT-CAPABILITY TLV, in the OPEN Object to advertise
   its support for PCEP Loss-Measurement extensions.  The presence of
   the LOSS-MEASUREMENT-CAPABILITY TLV in the OPEN Object (in the Open
   message) indicates that the Loss Measurement capability is supported
   as described in this document.  Additional procedure is defined as
   following:

   o  The PCEP protocol extensions for Loss Measurement MUST NOT be used
      if one or both PCEP Speakers have not included the LOSS-
      MEASUREMENT-CAPABILITY TLV in their respective Open message.

   o  If the PCEP speaker that supports the extensions of this document
      but did not advertise this capability, then upon receipt of LOSS-
      MEASUREMENT-ATTRIBUTES TLV in LSPA object, it SHOULD generate a
      PCErr with error-type 19 (Invalid Operation), error-value TBD8
      (Loss-Measurement capability was not advertised) and it will
      terminate the PCEP session.

   o  Similarly, the PCEP speaker SHOULD generate error-value TBD9
      (Bidirectional Measurement capability was not advertised) and



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      TBD10 (Unidirectional Measurement capability was not advertised)
      upon receipt of LOSS-MEASUREMENT-ATTRIBUTES TLV in LSPA object
      with two-way measurement request and one-way measurement request,
      respectively, when it did not advertise this capability.

   o  Further, the PCEP speaker SHOULD generate error-value TBD11
      (Inferred Mode Loss Measurement capability was not advertised) and
      TBD12 (Direct Mode Loss Measurement capability was not advertised)
      upon receipt of LOSS-MEASUREMENT-ATTRIBUTES TLV in LSPA object
      with Inferred Mode loss measurement request and Direct Mode loss
      measurement request, respectively, when it did not advertise this
      capability.

   o  If the PCEP speaker that supports the extensions of this document
      but did not advertise this capability, then upon receipt of LOSS-
      MEASUREMENT object, it SHOULD generate a PCErr with error-type 19
      (Invalid Operation), error-value TBD8 (Loss-Measurement capability
      was not advertised) and it will terminate the PCEP session.


6.1.1.  LOSS-MEASUREMENT-CAPABILITY TLV

   The LOSS-MEASUREMENT-CAPABILITY TLV is an optional TLV for use in the
   OPEN Object for Loss Measurement via PCEP capability advertisement.
   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=TBD2        |           Length=4            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Flags                     |N|I|B|U|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                LOSS-MEASUREMENT-CAPABILITY TLV Format

   The Type of the TLV is TBD2 and it has a fixed length of 4 bytes.

   The value comprises a single field - Flags (32 bits):

   o  U (Unidirectional Measurement - 1 bit): if set to 1 by a PCC, the
      U Flag indicates that the PCC allows reporting of unidirectional
      loss measurement information; if set to 1 by a PCE, the U Flag
      indicates that the PCE is capable of receiving unidirectional loss
      measurement information from the PCC.

   o  B (Bidirectional Measurement - 1 bit): if set to 1 by a PCC, the B
      Flag indicates that the PCC allows reporting of bidirectional loss



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      measurement information; if set to 1 by a PCE, the B Flag
      indicates that the PCE is capable of receiving bidirectional loss
      measurement information from the PCC.  Bidirectional measurement
      is only applicable to the bidirectional LSPs (e.g. MPLS-TP LSPs
      [RFC5921]).

   o  I (Inferred Loss Measurement Mode - 1 bit): if set to 1 by a PCC,
      the I Flag indicates that the PCC allows reporting of inferred
      mode loss measurement [RFC6374] information; if set to 1 by a PCE,
      the I Flag indicates that the PCE is capable of receiving inferred
      mode loss measurement information from the PCC.

   o  N (Direct Loss Measurement Mode - 1 bit): if set to 1 by a PCC,
      the N Flag indicates that the PCC allows reporting of direct mode
      loss measurement [RFC6374] information; if set to 1 by a PCE, the
      N Flag indicates that the PCE is capable of receiving direct mode
      loss measurement information from the PCC.

   Unassigned bits are considered reserved.  They MUST be set to 0 when
   sent and MUST be ignored when received.

   Advertisement of the LOSS-MEASUREMENT-CAPABILITY TLV implies support
   of loss measurement, as well as the objects, TLVs and procedures
   defined in this document.  Either U or B flag MUST be set in the TLV.
    Similarly, either I or N flag MUST be set in the TLV.

6.2.  LOSS-MEASUREMENT-ATTRIBUTES TLV

   The LOSS-MEASUREMENT-ATTRIBUTES TLV provides the configurable
   parameters of the loss measurement feature.

   The format of the LOSS-MEASUREMENT-ATTRIBUTES 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |       PCEP TLV Type TBD16     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   //                           sub-TLVs                          //
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  LOSS-MEASUREMENT-ATTRIBUTES TLV Format

   PCEP TLV Type is defined as following:




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    Type      Name
    ----------------------------------------------------------
     TBD16    LOSS-MEASUREMENT-ATTRIBUTES

   Length: The Length field defines the length of the value portion in
   bytes as per [RFC5440].

   Value: Comprises of one or more sub-TLVs as described in Section 4 of
   this document.

   The following sub-sections describe the parameters which are
   currently defined to be carried within this TLV.

6.2.1.  Loss Measurement Enable

   The Measurement-Enable sub-TLV specifies the loss measurement mode
   enabled using following flags:

   Bit      Description
   ------------------------------------------------------------------
    29      Unidirectional Loss Measurement Enabled
    28      Bidirectional Loss Measurement Enabled
    27      Inferred Loss Measurement Enabled

6.2.2.  Loss Measurement Interval

   The Measurement-Interval sub-TLV specifies a time interval in seconds
   for the loss measurement.

6.2.3.  Loss Measurement Report Threshold

   The Report-Threshold sub-TLV specifies the threshold value used to
   trigger an immediate reporting of the loss measurements bypassing the
   report-interval.

   o  Report-Threshold: This 24-bit field identifying the packet loss as
      a percentage of the total packets sent or received. The encoding
      is as per [RFC7471].

   Same report-threshold is used for all loss measurement values.

6.2.4.  Loss Measurement Report Threshold Percentage

   The Report-Threshold-Percentage sub-TLV specifies the threshold value
   used to trigger an immediate reporting of the loss measurements
   bypassing the report-interval.

   Same report-threshold-percentage is used for all loss measurement



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   values.

6.2.5.  Loss Measurement Report Interval

   The Report-Interval sub-TLV specifies the time interval in seconds
   when measured loss values are to be reported.

6.2.6.  Loss Measurement Upper Bound

   The Report-Upper-Bound sub-TLV specifies the upper-bound value in
   percentage packet loss, and is used to trigger an immediate reporting
   of the packet loss values when crossed.  This may also result in PCC
   taking an immediate local action on the LSP.


6.3.  LOSS-MEASUREMENT Object

   The LOSS-MEASUREMENT Object with Object-Class (Value TBD6) is defined
   in this document to report the packet loss measurement of a TE LSP.

   When the LSP is enabled with the loss measurement feature, the PCC
   SHOULD include the LOSS-MEASUREMENT Object to report the measured
   packet loss to the PCE in the PCRpt message.

     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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Class=TBD6    |   OT  |Res|P|I|   Object Length (bytes)       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   //                        (Object body)                        //
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    LOSS-MEASUREMENT Object Format

   Object Length (16 bits):  Specifies the total object length including
        the header, in bytes [RFC5440].

   Object-Types (OT) are defined as following:

   Object-Type  Len   Name
   --------------------------------------------------------------
    1           8     Tx Packets-Lost
    2           8     Rx Packets-Lost

   The object body format is defined as following:




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     0                   1                   2                   3
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     RESERVED  |            Packets-Lost                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

          LOSS-MEASUREMENT Object Body Formats (Tx and Rx)

   o  Packets-Lost: This 24-bit field identifying the packet loss as a
      percentage of the total packets sent or received, encoded as per
      [RFC7471].

   o  RESERVED: This field is reserved for future use.  It MUST be set
      to 0 when sent and MUST be ignored when received.

   The Packets-Lost in the Rx direction is reported when bidirectional
   loss measurement is enabled.


7.  PCEP Extensions for Reporting Bandwidth Utilization

7.1.  Bandwidth Utilization Capability Advertisement

   During PCEP Initialization Phase, PCEP Speakers (PCE or PCC)
   advertise their support of bandwidth utilization reporting.  A PCEP
   Speaker includes the "BANDWIDTH-UTILIZATION-CAPABILITY" TLV, in the
   OPEN Object to advertise its support for PCEP extension.  The
   presence of the "BANDWIDTH-UTILIZATION-CAPABILITY" TLV in the OPEN
   Object (in the Open message) indicates that the bandwidth utilization
   reporting is supported as described in this document.  Additional
   procedure is defined as following:

   o  The PCEP protocol extensions for bandwidth utilization MUST NOT be
      used if one or both PCEP Speakers have not included the
      "BANDWIDTH-UTILIZATION-CAPABILITY" TLV in their respective Open
      message.

   o  If the PCEP speaker that supports the extensions of this document
      but did not advertise this capability, then upon receipt of
      BANDWIDTH-UTILIZATION-ATTRIBUTES TLV in LSPA object, it SHOULD
      generate a PCErr with error-type 19 (Invalid Operation), error-
      value TBD13 (Bandwidth utilization capability was not advertised)
      and it will terminate the PCEP session.

   o  If the PCEP speaker that supports the extensions of this document
      but did not advertise this capability, then upon receipt of
      BANDWIDTH object of type TBD14, it SHOULD generate a PCErr with
      error-type 19 (Invalid Operation), error-value TBD13 (Bandwidth



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      utilization capability was not advertised) and it will terminate
      the PCEP session.

7.1.1.  BANDWIDTH-UTILIZATION-CAPABILITY TLV

   The BANDWIDTH-UTILIZATION-CAPABILITY TLV is an optional TLV for use
   in the OPEN Object for Bandwidth Utilization reporting via PCEP
   capability advertisement.  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=TBD3       |            Length=4           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Flags                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             BANDWIDTH-UTILIZATION-CAPABILITY TLV Format

   The Type of the TLV is TBD3 and it has a fixed length of 4 bytes.

   The value comprises a single field - Flags (32 bits).  Currently no
   flags are defined for this TLV.

   Unassigned bits are considered reserved.  They MUST be set to 0 when
   sent and MUST be ignored when received.

   Advertisement of the BANDWIDTH-UTILIZATION-CAPABILITY TLV implies
   support of bandwidth utilization reporting, as well as the objects,
   TLVs and procedures defined in this document.

7.2.  BW-UTILIZATION-MEASUREMENT-ATTRIBUTES TLV

   The BW-UTILIZATION-MEASUREMENT-ATTRIBUTES TLV provides the
   configurable parameters of bandwidth utilization feature.

   The format of the BW-UTILIZATION-MEASUREMENT-ATTRIBUTES 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |       PCEP TLV Type TBD17     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   //                           sub-TLVs                          //



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   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             BW-UTILIZATION-MEASUREMENT-ATTRIBUTES TLV Format

   PCEP TLV Type is defined as following:

    Type      Name
    ----------------------------------------------------------
     TBD17    BW-UTILIZATION-MEASUREMENT-ATTRIBUTES

   Length: The Length field defines the length of the value portion in
   bytes as per [RFC5440].

   Value: Comprises of one or more sub-TLVs as described in Section 4 of
   this document.

   The following sub-sections describe the parameters which are
   currently defined to be carried within this TLV.

7.2.1.  Bandwidth Utilization Measurement Enable

   The Measurement-Enable sub-TLV specifies that the bandwidth
   utilization reporting is enabled using following flag:

   Bit     Description
   ------------------------------------------------------------------
    26     Bandwidth Utilization Reporting Enabled

7.2.2.  Bandwidth Utilization Measurement Interval

   The Measurement-Interval sub-TLV specifies a time interval in seconds
   for the bandwidth samples collection interval.

7.2.3.  Bandwidth Utilization Report Threshold

   The Report-Threshold sub-TLV is used to decide if the bandwidth
   samples collected so far should be immediately reported bypassing the
   report-interval.

   o  Threshold: The absolute threshold bandwidth value in 32-bits,
      encoded in IEEE floating point format (see [IEEE.754.1985]),
      expressed in bytes per second.

7.2.4.  Bandwidth Utilization Report Threshold Percentage

   The Report-Threshold-Percentage sub-TLV is used to decide if the
   bandwidth samples collected so far should be immediately reported



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   bypassing the report-interval.

7.2.5.  Bandwidth Utilization Report Interval

   The Report-Interval sub-TLV specifies a time interval in seconds when
   the collected bandwidth samples are to be reported to PCE.

7.2.6.  Bandwidth Utilization Upper Bound

   The Report-Upper-Bound sub-TLV specifies the upper-bound bandwidth
   encoded in IEEE floating point format (see [IEEE.754.1985]),
   expressed in bytes per second, and is used to trigger an immediate
   reporting when crossed.  This may also result in PCC taking an
   immediate local action on the LSP.


7.3.  BANDWIDTH Object

   A new object-type for BANDWIDTH object (Object-Class 5) is defined to
   report the bandwidth utilization of a TE LSP.

   When the TE LSP is enabled with the bandwidth utilization reporting,
   the PCC SHOULD include the BANDWIDTH-UTILIZATION Object to report the
   bandwidth utilization of the TE LSP to the PCE in the PCRpt message.

   The object-type is TBD14, the object length is variable with
   multiples of 4 bytes.

   The object body format is defined as following:

     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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        BwSample1                              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                           ...                                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        BwSampleN                              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                BANDWIDTH-UTILIZATION Object Body Format

   o  BwSample: The utilized bandwidth, (the BwSample collected at the
      end of each measurement-interval) encoded in IEEE floating point
      format (see [IEEE.754.1985]), expressed in bytes per second.


8.  PCEP Procedure



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   Following procedure is defined for the extensions to different PCEP
   messages for reporting performance measurements.

8.1.  Various MEASUREMENT-ATTRIBUTES TLVs

   o  For a PCE-Initiated LSP [DRAFT-PCE-INITIATED-LSP] with reporting
      features enabled, the corresponding MEASUREMENT-ATTRIBUTES TLV for
      each measurement MUST be included in the LSPA Object with the
      PCInitiate message.

   o  For a PCE-Initiated LSP [DRAFT-PCE-INITIATED-LSP] with reporting
      features enabled, the corresponding MEASUREMENT-ATTRIBUTES TLV for
      each measurement is carried in the PCUpd message in the LSPA
      Object in order to make updates to the attributes such as
      Report-Interval.

   o  For a PCC-Initiated LSP with reporting features enabled, when the
      LSP is delegated to the PCE, the corresponding MEASUREMENT-
      ATTRIBUTES TLV for each measurement MUST be included in the LSPA
      Object of the PCRpt message.

   o  The various MEASUREMENT-ATTRIBUTES TLVs are encoded in all PCEP
      messages for the LSP with reporting features enabled, the absence
      of the corresponding MEASUREMENT-ATTRIBUTES TLV indicates that the
      PCEP speaker wishes to disable the feature.

8.2.  The MEASUREMENT Objects

   When a TE LSP is enabled with a measurement reporting feature, the
   PCC SHOULD include the corresponding MEASUREMENT Object to report the
   measured values to the PCE in the PCRpt message [DRAFT-PCE-
   STATEFUL].

   The format of the "actual_attribute-list" in the PCRpt message is
   modified as following:

         <actual_attribute-list>::=[<BANDWIDTH>]
                                   [<DELAY-MEASUREMENT>]
                                   [<LOSS-MEASUREMENT>]
                                   [<metric-list>]


9.  Scaling Considerations

   It should be noted that when measurement reporting is deployed under
   LSP scale, it can lead to frequent reporting updates to the PCE.
   Operators are advised to set the values of various measurement
   reporting parameters appropriate for the deployed LSP scale.



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   If a PCE gets overwhelmed, it can notify the PCC to temporarily
   suspend the reporting of the measurements as described below.

9.1.  The PCNtf Message

   As per [RFC5440], the PCEP Notification message (PCNtf) can be sent
   by a PCEP speaker to notify its peer of a specific event.  A PCEP
   speaker SHOULD notify its PCEP peer that it is overwhelmed, and on
   receipt of such notification the peer SHOULD NOT send any PCEP
   messages related to measurement reporting.  If a PCEP message related
   to measurement reporting is received, it MUST be silently ignored.

   o  When a PCEP speaker is overwhelmed, it SHOULD notify its peer by
      sending a PCNtf message with Notification Type = TBD15 (PM
      Overwhelm State) and Notification Value = 1 (Entering PM overwhelm
      state).

   o  Optionally, OVERLOADED-DURATION TLV [RFC5440] MAY be included that
      specifies the time period during which no further PCEP messages
      related to PM should be sent.

   o  When the PCEP speaker is no longer in the overwhelm state and is
      available to process the PM reporting, it SHOULD notify its peer
      by sending a PCNtf message with Notification Type = TBD15 (PM
      Overwhelm State) and Notification Value = 2 (Clearing PM overwhelm
      state).


10.  Security Considerations

   This document defines new MEASUREMENT-ATTRIBUTES TLVs, CAPABILITY
   TLVs and MEASUREMENT Objects for reporting loss, delay measurements
   and bandwidth utilization which do not add additional security
   concerns beyond those discussed in [RFC5440] and
   [DRAFT-PCE-STATEFUL].

   Some deployments may find the reporting of the performance
   measurement and bandwidth utilization information as extra sensitive
   as it could be used to influence LSP path computation and LSP setup
   with adverse effect.  Additionally, snooping of PCEP messages with
   such data or using PCEP messages for network reconnaissance, may give
   an attacker sensitive information about the operations of the
   network.  Thus, such deployment should employ suitable PCEP security
   mechanisms like TCP Authentication Option (TCP-AO) [RFC5925] or
   [DRAFT-PCE-PCEPS].


11.  Manageability Considerations



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11.1.  Control of Function and Policy

   The performance measurement reporting SHOULD be controlled per TE
   tunnel (at PCC or PCE) and the values for feature attributes e.g.
   measurement-interval, report-interval, report-threshold SHOULD be
   configurable by an operator.

11.2.  Information and Data Models

   A Management Information Base (MIB) module for modeling PCEP is
   described in [RFC7420].  However, one may prefer the mechanism for
   configuration using YANG data model [DRAFT-PCE-PCEP-YANG].  These
   SHOULD be enhanced to provide controls and indicators for support of
   performance measurement reporting feature.  Support for various
   configuration knobs as well as counters of messages sent/received
   containing the TLVs (defined in this document) SHOULD be added.

11.3.  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].

11.4.  Verify Correct Operations

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

11.5.  Requirements On Other Protocols

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

11.6.  Impact On Network Operations

   In order to avoid any unacceptable impact on network operations, an
   implementation SHOULD allow a limit to be placed on the number of
   LSPs that can be enabled with performance measurement reporting
   feature.  An implementation MAY allow a limit to be placed on the
   rate of measurement reporting messages sent by a PCEP speaker and
   received by a peer.  An implementation MAY also allow sending a
   notification when a PCEP speaker is overwhelmed or the rate of
   messages reach a threshold.


12.  IANA Considerations




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12.1.  Measurement Capability TLV Types

   This document defines the following new PCEP TLVs; IANA is requested
   to make the following allocations from the "PCEP TLV Type Indicators"
   registry.  <http://www.iana.org/assignments/pcep/pcep.xhtml#pcep-tlv-
   type-indicators>

   Type      Name                                 Reference
   --------------------------------------------------------------
    TBD1     DELAY-MEASUREMENT-CAPABILITY         [This document]
    TBD2     LOSS-MEASUREMENT-CAPABILITY          [This document]
    TBD3     BANDWIDTH-UTILIZATION-CAPABILITY     [This document]

12.1.1.  Flag Fields for MEASUREMENT-CAPABILITY TLVs

   IANA is requested to create a registry to manage the Flag field of
   the DELAY-MEASUREMENT-CAPABILITY TLV, LOSS-MEASUREMENT-CAPABILITY TLV
   and BANDWIDTH-UTILIZATION-CAPABILITY TLV.

   New bit numbers are allocated only by an IETF Review 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 value are defined in this document for the Flag field
   for -

   DELAY-MEASUREMENT-CAPABILITY TLV:

    Bit       Description                            Reference
    ----------------------------------------------------------------
    31        One-way Delay Measurement              [This document]
    30        Two-way Delay Measurement              [This document]

   LOSS-MEASUREMENT-CAPABILITY TLV:

    Bit       Description                            Reference
    ----------------------------------------------------------------
    31        Unidirectional Loss Measurement        [This document]
    30        Bidirectional Loss Measurement         [This document]
    29        Inferred Loss Measurement Mode         [This document]
    28        Direct Loss Measurement Mode           [This document]




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12.2.  MEASUREMENT-ATTRIBUTES TLVs

   This document defines the following new PCEP TLV Types; IANA is
   requested to make the following TLV type allocations from the "PCEP
   TLV Type Indicators" registry.
   <http://www.iana.org/assignments/pcep/pcep.xhtml#pcep-tlv-type-
   indicators>

   Type      Name                                    Reference
   -----------------------------------------------------------------
    TBD4     DELAY-MEASUREMENT-ATTRIBUTES            [This document]
    TBD16    LOSS-MEASUREMENT-ATTRIBUTES             [This document]
    TBD17    BW-UTILIZATION-MEASUREMENT-ATTRIBUTES   [This document]

12.2.1.  The Sub-TLVs For MEASUREMENT-ATTRIBUTES TLVs

   IANA is requested to create an "MEASUREMENT-ATTRIBUTES Sub-TLV Types"
   sub-registry in the "PCEP TLV Type Indicators" registry.  New sub-TLV
   are allocated only by an IETF Review action [RFC5226].

   This document defines the following sub-TLV types:

   Type      Name                                 Reference
   --------------------------------------------------------------
    0        Reserved                             [This document]
    1        Measurement-Enable sub-TLV           [This document]
    2        Measurement-Interval sub-TLV         [This document]
    3        Report-Threshold sub-TLV             [This document]
    4        Report-Threshold-Percentage sub-TLV  [This document]
    5        Report-Interval sub-TLV              [This document]
    6        Report-Upper-Bound sub-TLV           [This document]
    7-       Unassigned                           [This document]
   65535

12.2.1.1.  Flag Fields in Measurement-Enable sub-TLV

   IANA is requested to create a registry to manage the Flag field of
   the Measurement-Enable sub-TLV.

   New bit numbers are allocated only by an IETF Review 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




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   The following value are defined in this document for the Flag field.

   Bit     Description                              Reference
   ----------------------------------------------------------------
    31     One-Way Delay Measurement Enabled        [This document]
    30     Two-Way Delay Measurement Enabled        [This document]
    29     Unidirectional Loss Measurement Enabled  [This document]
    28     Bidirectional Loss Measurement Enabled   [This document]
    27     Inferred Loss Measurement Enabled        [This document]
    26     Bandwidth Utilization Reporting Enabled  [This document]

12.3.  Measurement Object-Class

   This document defines Object-Class for the following Objects; IANA is
   requested to make the following allocations from the "PCEP Objects"
   registry.  <http://www.iana.org/assignments/pcep/pcep.xhtml#pcep-
   objects>

   Object-Class  Name                             Reference
   --------------------------------------------------------------
    TBD5         DELAY-MEASUREMENT Object         [This document]
    TBD6         LOSS-MEASUREMENT Object          [This document]

12.3.1.  DELAY-MEASUREMENT Object-Types

   IANA is requested to create an "DELAY-MEASUREMENT Object-Types"
   sub-registry for DELAY-MEASUREMENT Object (Object-class TBD5).

   This document defines the following object-types:

   Object-Type Name                                       Reference
   ---------------------------------------------------------------------
    0          Reserved                                  [This document]
    1          One-Way Delay Measurement Value           [This document]
    2          One-Way Delay Measurement Min/Max Values  [This document]
    3          One-Way Delay Variation Measurement Value [This document]
    4          Two-Way Delay Measurement Value           [This document]
    5          Two-Way Delay Measurement Min/Max Values  [This document]
    6          Two-Way Delay Variation Measurement Value [This document]

12.3.2.  LOSS-MEASUREMENT Object-Types

   IANA is requested to create an "LOSS-MEASUREMENT Object-Types"
   sub-registry for LOSS-MEASUREMENT Object (Object-class TBD6).

   This document defines the following object-types:





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   Object-Type Name                               Reference
   --------------------------------------------------------------
    0          Reserved                           [This document]
    1          Tx Packets-Lost                    [This document]
    2          Rx Packets-Lost                    [This document]

12.3.3.  BANDWIDTH Object-Type

   This document defines new Object-Type for the BANDWIDTH object
   (Object-Class 5, [RFC5440]); IANA is requested to make the following
   allocation from the "PCEP Objects" registry.
   <http://www.iana.org/assignments/pcep/pcep.xhtml#pcep-objects>

   Object-Type Name                               Reference
   --------------------------------------------------------------
    TBD14      BANDWIDTH-UTILIZATION Object       [This document]

12.4.  PCE Error Codes

   This document defines two new error-values for PCErr with error-code
   19 (Invalid Operation).  IANA is requested to make the following
   allocations.

   Error-Value    Name                                     Reference
   -------------------------------------------------------------------
    TBD7   Delay-Measurement capability
                                   was not advertised  [This document]
    TBD8   Loss-Measurement capability
                                   was not advertised  [This document]
    TBD9   Bidirectional Measurement capability
                                   was not advertised  [This document]
    TBD10  Unidirectional Measurement capability
                                   was not advertised  [This document]
    TBD11  Inferred Mode Loss Measurement capability
                                   was not advertised  [This document]
    TBD12  Direct Mode Loss Measurement capability
                                   was not advertised  [This document]
    TBD13  Bandwidth Utilization capability
                                   was not advertised  [This document]

12.5.  Notification Object-Type

   IANA is requested to allocate new Notification Types and Notification
   Values within the "Notification Object" sub-registry of the PCEP
   Numbers registry, as follows:

   Type        Meaning                                Reference
   ------------------------------------------------------------------



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    TBD15      PM Overwhelm State                     [This document]

               Notification-value=1:  Entering PM overwhelm state
               Notification-value=2:  Clearing PM overwhelm state















































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13.  References

13.1.  Normative References

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

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

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

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

   [DRAFT-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,
              (work in progress).

13.2.  Informative References

   [RFC5586]  Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed.,
              "MPLS Generic Associated Channel", RFC 5586, June 2009.

   [RFC5921]  Bocci, M., Ed., Bryant, S., Ed., Frost, D., Ed., Levrau,
              L., and L. Berger, "A Framework for MPLS in Transport
              Networks", RFC 5921, July 2010.

   [RFC5925]  Touch, J., Mankin, A., and R. Bonica, "The TCP
              Authentication Option", RFC 5925, June 2010.

   [RFC6374]  Frost, D. and S. Bryant, "Packet Loss and Delay
              Measurement for MPLS Networks", DOI 10.17487/RFC6374, RFC
              6374, September 2011.

   [RFC6375]  Frost, D. and S. Bryant, "A Packet Loss and Delay
              Measurement Profile for MPLS-Based Transport Networks",
              RFC 6375, September 2011.

   [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.



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   [RFC7471]  S. Giacalone, D. Ward, J. Drake, A. Atlas, and S. Previdi,
              "OSPF Traffic Engineering (TE) Metric Extensions", RFC
              7471, March 2015.

   [RFC7810]  S. Previdi, S. Giacalone, D. Ward, J. Drake, and Q. Wu,
              "IS-IS Traffic Engineering (TE) Metric Extensions", RFC
              7810, May 2016.

   [RFC7823]  Atlas, A., Drake, J., Giacalone, S., and S. Previdi,
              "Performance-Based Path Selection for Explicitly Routed
              Label Switched Paths (LSPs) Using TE Metric Extensions",
              RFC 7823, May 2016.

   [RFC7876]  Bryant, S., Sivabalan, S., and Soni, S., "UDP Return Path
              for Packet Loss and Delay Measurement for MPLS Networks",
              RFC 7876, July 2016.

   [DRAFT-PCE-PCEPS]  Lopez, D., Dios, O., Wu, W., and D. Dhody, "Secure
              Transport for PCEP", draft-ietf-pce-pceps, (work in
              progress).

   [DRAFT-PCE-SERVICE-AWARE]  Dhody, D., V. Manral, V., Ali, Z., and
              Kumaki, K., "Extensions to the Path Computation Element
              Communication Protocol (PCEP) to compute service aware
              Label Switched Path (LSP)", draft-ietf-pce-pcep-service-
              aware, (work in progress).

   [DRAFT-IDR-TE-PM-BGP]  Wu, Q., Danhua, W., Previdi, S., Gredler, H.,
              and S. Ray, "BGP attribute for North-Bound Distribution of
              Traffic Engineering (TE) performance Metrics", draft-ietf-
              idr-te-pm-bgp (work in progress).

   [DRAFT-PCE-PCEP-YANG]  Dhody, D., Hardwick, J., Beeram, V., and J.
              Tantsura, "A YANG Data Model for Path Computation Element
              Communications Protocol (PCEP)", draft-ietf-pce-pcep-yang
              (work in progress).

   [DRAFT-IETF-PCE-AUTOBW]  Dhody, D., Palle, U., Singh, R., Gandhi, R.,
              and L. Fang, "PCEP Extensions for MPLS-TE LSP Automatic
              Bandwidth Adjustment with Stateful PCE", draft-ietf-pce-
              stateful-pce-auto-bandwidth (work in progress).

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






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Acknowledgments

   TBA.


Authors' Addresses

   Rakesh Gandhi
   Cisco Systems, Inc.

   EMail: rgandhi@cisco.com


   Bin Wen
   Comcast

   EMail: Bin_Wen@cable.comcast.com


   Colby Barth
   Juniper Networks

   EMail: cbarth@juniper.net


   Dhruv Dhody
   Huawei Technologies
   India

   EMail: dhruv.ietf@gmail.com





















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