PCE Working Group D. Dhody
Internet-Draft U. Palle
Intended status: Standards Track Huawei Technologies
Expires: August 2, 2017 R. Singh
Juniper Networks
R. Gandhi
Individual Contributor
L. Fang
eBay
January 29, 2017
PCEP Extensions for MPLS-TE LSP Automatic Bandwidth Adjustment with
Stateful PCE
draft-ietf-pce-stateful-pce-auto-bandwidth-01
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.
Automatic bandwidth adjustment allows automatic and dynamic
adjustment of the reserved bandwidth allocation of an TE LSP based on
the volume of traffic flowing through it. This document describes
PCEP extensions for automatic bandwidth adjustment when employing an
Active Stateful PCE for both PCE-initiated and PCC-initiated LSPs.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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Copyright Notice
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Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 4
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
3. Requirements for PCEP Extensions . . . . . . . . . . . . . . . 5
4. Architectural Overview . . . . . . . . . . . . . . . . . . . . 6
4.1. Auto-Bandwidth Overview . . . . . . . . . . . . . . . . . 6
4.2. Auto-bandwidth Theory of Operation . . . . . . . . . . . . 8
4.3. Scaling Considerations . . . . . . . . . . . . . . . . . . 8
5. Extensions to the PCEP . . . . . . . . . . . . . . . . . . . . 9
5.1. Capability Advertisement . . . . . . . . . . . . . . . . . 9
5.1.1 AUTO-BANDWIDTH-CAPABILITY TLV . . . . . . . . . . . . . 9
5.2. AUTO-BANDWIDTH-ATTRIBUTE TLV . . . . . . . . . . . . . . . 10
5.2.1. Sample-Interval sub-TLV . . . . . . . . . . . . . . . 11
5.2.2. Adjustment-Interval sub-TLV . . . . . . . . . . . . . 12
5.2.3. Adjustment Threshold . . . . . . . . . . . . . . . . . 12
5.2.3.1. Adjustment-Threshold sub-TLV . . . . . . . . . . . 12
5.2.3.2. Adjustment-Threshold-Percentage sub-TLV . . . . . 13
5.2.4. Minimum and Maximum Bandwidth Values . . . . . . . . . 13
5.2.4.1. Minimum-Bandwidth sub-TLV . . . . . . . . . . . . 13
5.2.4.2. Maximum-Bandwidth sub-TLV . . . . . . . . . . . . 14
5.2.5. Overflow and Underflow Conditions . . . . . . . . . . 14
5.2.5.1. Overflow-Threshold sub-TLV . . . . . . . . . . . . 14
5.2.5.2. Overflow-Threshold-Percentage sub-TLV . . . . . . 15
5.2.5.3. Underflow-Threshold sub-TLV . . . . . . . . . . . 16
5.2.5.4. Underflow-Threshold-Percentage sub-TLV . . . . . . 17
5.3. BANDWIDTH Object . . . . . . . . . . . . . . . . . . . . . 17
5.4. The PCInitiate Message . . . . . . . . . . . . . . . . . . 18
5.5. The PCRpt Message . . . . . . . . . . . . . . . . . . . . 18
5.6. The PCNtf Message . . . . . . . . . . . . . . . . . . . . 18
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5.7. The PCUpd Message . . . . . . . . . . . . . . . . . . . . 19
6. Security Considerations . . . . . . . . . . . . . . . . . . . 19
7. Manageability Considerations . . . . . . . . . . . . . . . . . 19
7.1. Control of Function and Policy . . . . . . . . . . . . . . 19
7.2. Information and Data Models . . . . . . . . . . . . . . . 20
7.3. Liveness Detection and Monitoring . . . . . . . . . . . . 20
7.4. Verify Correct Operations . . . . . . . . . . . . . . . . 20
7.5. Requirements On Other Protocols . . . . . . . . . . . . . 20
7.6. Impact On Network Operations . . . . . . . . . . . . . . . 20
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21
8.1. PCEP TLV Type Indicators . . . . . . . . . . . . . . . . . 21
8.2. AUTO-BANDWIDTH-CAPABILITY TLV Flag Field . . . . . . . . . 21
8.3. AUTO-BANDWIDTH-ATTRIBUTE Sub-TLV . . . . . . . . . . . . . 21
8.4. Error Object . . . . . . . . . . . . . . . . . . . . . . . 22
8.5. Notification Object . . . . . . . . . . . . . . . . . . . 22
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 22
9.1. Normative References . . . . . . . . . . . . . . . . . . . 22
9.2. Informative References . . . . . . . . . . . . . . . . . . 23
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 25
Contributors' Addresses . . . . . . . . . . . . . . . . . . . . . 25
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 26
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).
[I-D.ietf-pce-stateful-pce] specifies extensions to PCEP to enable
stateful control of MPLS TE LSPs. It describes two mode of
operations - Passive stateful PCE and Active stateful PCE. In this
document, the focus is on Active stateful PCE where LSPs are
configured at the PCC and control over them is delegated to the PCE.
Further [I-D.ietf-pce-pce-initiated-lsp] describes the setup,
maintenance and teardown of PCE-initiated LSPs for the stateful PCE
model.
Over time, based on the varying traffic pattern, an LSP established
with certain bandwidth may require to adjust the bandwidth, reserved
in the network automatically. Ingress Label Switch Router (LSR)
collects the traffic rate at each sample interval to determine the
bandwidth demand of the LSP. This bandwidth information is then used
to adjust the LSP bandwidth periodically. This feature is commonly
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referred to as Auto-Bandwidth.
Enabling Auto-Bandwidth feature on an LSP results in the LSP
automatically adjusting its bandwidth reservation based on the actual
traffic flowing through the LSP. The initial LSP bandwidth can be
set to an arbitrary value (including zero), in practice, it can be
operator expected value based on design and planning. Once the LSP
is set-up, the LSP 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 the traffic flow. The Auto-Bandwidth is described in
detail in Section 4.1. [RFC8051] describes the use-case for Auto-
Bandwidth adjustment for passive and active stateful PCE.
The PCC (head-end of the LSP) monitors the traffic flowing through
the LSP and calculates the new adjusted bandwidth. The PCC reports
the calculated bandwidth to be adjusted to the PCE. This is similar
to a passive stateful PCE model, while the passive stateful PCE uses
path request/reply mechanism, the active stateful PCE uses
report/update mechanism to adjust the LSP bandwidth. In case of PCE-
initiated LSP, the PCC is requested during the LSP initiation to
monitor and calculate the new adjusted bandwidth.
This document defines extensions needed to support Auto-Bandwidth
feature on the LSPs in a active stateful PCE model using PCEP.
Note that, another document [I-D.gandhi-pce-pm], describes the PCEP
extensions to report the performance measurements to the PCE, this
includes the bandwidth usage information of a TE LSP and can be used
at the PCE to calculate the new bandwidth to be adjusted.
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 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.
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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 Auto-Bandwidth feature specific terms defined in Section
4.1.
3. Requirements for PCEP Extensions
The PCEP speaker supporting this document MUST have a mechanism to
advertise the automatic bandwidth adjustment capability.
PCEP extensions required are summarized in the following table.
+---------------------------------+---------------------------------+
| PCC Initiated | PCE Initiated |
+---------------------------------+---------------------------------+
| | |
| PCC monitors the traffic | At the time of initiation, |
| and reports the calculated | PCE request PCC to monitor |
| bandwidth to be adjusted | the traffic and report the |
| to the PCE. | calculated bandwidth to be |
| | adjusted to the PCE. |
| | |
| Extension is needed for PCC | Extension is needed for PCE |
| to pass on the adjustment | to pass on the adjustment |
| parameters at the time of | parameters at the time of |
| Delegation. | Initiation. |
| | |
+---------------------------------+---------------------------------+
Table 1: Auto-Bandwidth PCEP extensions
Further Auto-Bandwidth deployment considerations are summarized
below:
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o It is required to identify and inform the PCEP peer, the LSP that
are enabled with Auto-Bandwidth feature. Not all LSPs in some
deployments would like their bandwidth to be dependent on the
real-time bandwidth usage but be constant as set by the operator.
o Further for the LSP with Auto-Bandwidth feature enabled, an
operator should be able to specify the adjustment parameters (i.e.
configuration knobs) to control this feature (e.g. minimum/
maximum bandwidth range) and PCEP peer should be informed.
4. Architectural Overview
4.1. Auto-Bandwidth Overview
Auto-Bandwidth feature allows automatic and dynamic adjustment of the
reserved bandwidth of an LSP over time, i.e. without network operator
intervention. The bandwidth adjustment uses the make-before-break
signaling method so that there is no interruption to the 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 in the network. With
Auto-Bandwidth feature, the LSP bandwidth can be set to some
arbitrary value (including zero) during initial setup time, and it
will be periodically adjusted over time based on the actual bandwidth
requirement.
Note the following definitions of the Auto-Bandwidth terms:
Maximum Average Bandwidth (MaxAvgBw): The maximum average bandwidth
represents the current traffic bandwidth demand during a time
interval. This is the maximum value of the averaged traffic
bandwidth rate in a given adjustment-interval.
Adjusted Bandwidth: This is the Auto-Bandwidth computed bandwidth
that needs to be adjusted for the LSP.
Sample-Interval: The periodic time interval at which the traffic
rate is collected as a sample.
Bandwidth-Sample (BwSample): The bandwidth sample collected at every
sample interval to measure the traffic rate.
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Adjustment-Interval: The periodic time interval at which the
bandwidth adjustment should be made using the MaxAvgBw.
Maximum-Bandwidth: The maximum bandwidth that can be reserved for
the LSP.
Minimum-Bandwidth: The minimum bandwidth that can be reserved for
the LSP.
Adjustment-Threshold: This value is used to decide when the
bandwidth should be adjusted. If the percentage or absolute
difference between the current MaxAvgBw and the current bandwidth
reservation is greater than or equal to the threshold value, the
LSP bandwidth is adjusted to the current bandwidth demand
(Adjusted Bandwidth) at the adjustment-interval expiry.
Overflow-Count: This value is used to decide when the bandwidth
should be adjusted when there is a sudden increase in traffic
demand. This value indicates how many times consecutively, the
percentage or absolute difference between the current MaxAvgBw and
the current bandwidth reservation is greater than or equal to the
Overflow-Threshold value.
Overflow-Threshold: This value is used to decide when the bandwidth
should be adjusted when there is a sudden increase in traffic
demand. If the percentage or absolute difference between the
current MaxAvgBw and the current bandwidth reservation is greater
than or equal to the threshold value, the overflow-condition is
set to be met. The LSP bandwidth is adjusted to the current
bandwidth demand bypassing the adjustment-interval if the
overflow-condition is met consecutively for the Overflow-Count.
Underflow-Count: This value is used to decide when the bandwidth
should be adjusted when there is a sudden decrease in traffic
demand. This value indicates how many times consecutively, the
percentage or absolute difference between the current MaxAvgBw and
the current bandwidth reservation is greater than or equal to the
Underflow-Threshold value.
Underflow-Threshold: This value is used to decide when the bandwidth
should be adjusted when there is a sudden decrease in traffic
demand. If the percentage or absolute difference between the
current MaxAvgBw and the current bandwidth reservation is greater
than or equal to the threshold value, the underflow-condition is
set to be met. The LSP bandwidth is adjusted to the current
bandwidth demand bypassing the adjustment-interval if the
underflow-condition is met consecutively for the Underflow-Count.
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4.2. Auto-bandwidth Theory of Operation
The traffic rate is periodically sampled at each sample-interval
(which can be configured by the user and the default value as 5
minutes) by the PCC which is the head-end node of the LSP. 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 PCC is in-charge of calculating the bandwidth to be
adjusted, will adjust the bandwidth of the LSP to the highest sampled
traffic rate (MaxAvgBw) amongst the set of bandwidth samples
collected over the adjustment-interval.
Note that the highest sampled traffic rate could be higher or lower
than the current LSP bandwidth. Only if the difference between the
current bandwidth demand (MaxAvgBw) and the current bandwidth
reservation is greater than or equal to the Adjustment-Threshold
(percentage or absolute value), the LSP bandwidth is adjusted to the
current bandwidth demand (MaxAvgBw). Some LSPs are less eventful
while other LSPs may encounter a lot of changes in the traffic
pattern. The intervals for adjustment is based on the traffic
pattern of the LSP.
In order to avoid frequent re-signaling, an operator may set a longer
adjustment-interval value. However, longer adjustment-interval can
result in an undesirable effect of masking sudden changes in traffic
demands of an LSP. To avoid this, the Auto-Bandwidth feature may
pre-maturely expire the adjustment-interval and adjust the LSP
bandwidth to accommodate the sudden bursts of increase in traffic
demand as an overflow condition or decrease in traffic demand as an
underflow condition.
All thresholds in this document could be represented in both absolute
value and percentage, and could be used together.
4.3. Scaling Considerations
It should be noted that any bandwidth change would require re-
signaling of an LSP in a make-before-break fashion, which can further
trigger preemption of lower priority LSPs in the network. When
deployed under scale, this can lead to a signaling churn in the
network. The Auto-bandwidth application algorithm is thus advised to
take this into consideration before adjusting the LSP bandwidth.
Operators are advised to set the values of various auto-bandwidth
adjustment parameters appropriate for the deployed LSP scale.
If a PCE gets overwhelmed, it can notify the PCC to temporarily
suspend the reporting of the new bandwidth to be adjusted (see
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Section 5.6). Similarly if a PCC gets overwhelmed due to signaling
churn, it can notify the PCE to temporarily suspend the LSP bandwidth
adjustment.
5. Extensions to the PCEP
5.1. Capability Advertisement
During PCEP Initialization Phase, PCEP Speakers (PCE or PCC)
advertise their support of Automatic Bandwidth Adjustment. A PCEP
Speaker includes the "Auto-Bandwidth Capability" TLV, in the OPEN
Object to advertise its support for PCEP Auto-Bandwidth extensions.
The presence of the "Auto-Bandwidth Capability" TLV in the OPEN
Object indicates that the Automatic Bandwidth Adjustment is supported
as described in this document.
The PCEP protocol extensions for Auto-Bandwidth adjustments MUST NOT
be used if one or both PCEP Speakers have not included the "Auto-
Bandwidth Capability" TLV in their respective OPEN message. If the
PCEP speaker that supports the extensions of this draft but did not
advertise this capability, then upon receipt of AUTO-BANDWIDTH-
ATTRIBUTE TLV in LSPA object, it SHOULD generate a PCErr with error-
type 19 (Invalid Operation), error-value TBD4 (Auto-Bandwidth
capability was not advertised) and it will terminate the PCEP
session.
5.1.1 AUTO-BANDWIDTH-CAPABILITY TLV
The AUTO-BANDWIDTH-CAPABILITY TLV is an optional TLV for use in the
OPEN Object for Automatic Bandwidth Adjustment 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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
AUTO-BANDWIDTH-CAPABILITY TLV format
The type of the TLV is (TBD2) and it has a fixed length of 4 octets.
The value comprises a single field - Flags (32 bits). Currently no
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flags are defined for this TLV.
Unassigned bits are considered reserved. They MUST be set to 0 on
transmission and MUST be ignored on receipt.
Advertisement of the Auto-Bandwidth capability TLV implies support of
auto-bandwidth adjustment, as well as the objects, TLVs and
procedures defined in this document.
5.2. AUTO-BANDWIDTH-ATTRIBUTE TLV
The AUTO-BANDWIDTH-ATTRIBUTE TLV provides the 'configurable knobs' of
the feature and it can be included as an optional TLV in the LSPA
Object (as described in [RFC5440]).
For PCE-Initiated LSP ([I-D.ietf-pce-pce-initiated-lsp]), this TLV is
included in the LSPA Object with the PCInitiate message. For
delegated LSPs, this TLV is carried in the PCRpt message in LSPA
Object. This TLV is also included in the LSPA object with the PCUpd
message to direct the PCE to use different parameters with the LSP.
The TLV is encoded in all PCEP messages for the LSP while the auto
bandwidth adjustment feature is enabled, the absence of the TLV
indicate the PCEP speaker wish to disable the feature.
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=TBD1 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// sub-TLVs //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
AUTO-BANDWIDTH-ATTRIBUTE TLV format
Type: TBD1
Length: The Length field defines the length of the value portion in
bytes as per [RFC5440].
Value: This comprises one or more sub-TLVs.
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Following sub-TLVs are defined in this document:
Type Len Name
-------------------------------------------------------------------
1 4 Sample-Interval sub-TLV
2 4 Adjustment-Interval sub-TLV
3 4 Adjustment-Threshold sub-TLV
4 4 Adjustment-Threshold-Percentage sub-TLV
5 4 Minimum-Bandwidth sub-TLV
6 4 Maximum-Bandwidth sub-TLV
7 8 Overflow-Threshold sub-TLV
8 4 Overflow-Threshold-Percentage sub-TLV
9 8 Underflow-Threshold sub-TLV
10 4 Underflow-Threshold-Percentage sub-TLV
Future specification can define additional sub-TLVs.
The presence of AUTO-BANDWIDTH-ATTRIBUTE TLV in LSPA Object means
that the automatic bandwidth adjustment feature is enabled. All
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.
The AUTO-BANDWIDTH-ATTRIBUTE TLV can also be carried in PCUpd message
in LSPA Object in order to make updates to auto-bandwidth attributes
such as Adjustment-Interval.
If sub-TLVs are not present, the default values based on the local
policy are assumed.
The sub-TLVs are encoded to inform the PCEP peer the various sampling
and adjustment parameters.
The following sub-sections describe the sub-TLVs which are currently
defined to be carried within the AUTO-BANDWIDTH-ATTRIBUTE TLV.
5.2.1. Sample-Interval sub-TLV
The Sample-Interval sub-TLV specifies a time interval in seconds at
which traffic samples are collected at the PCC.
The Type is 1, Length is 4, and the value comprises of 4-octet time
interval, the valid range is from 1 to 604800, in seconds. The
default value is 300 seconds.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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| Type=1 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sample-Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Sample-Interval sub-TLV format
5.2.2. Adjustment-Interval sub-TLV
The Adjustment-Interval sub-TLV specifies a time interval in seconds
at which bandwidth adjustment should be made.
The Type is 2, Length is 4, and the value comprises of 4-octet time
interval, the valid range is from 1 to 604800, in seconds. The
default value is 300 seconds.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Adjustment-Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Adjustment-Interval sub-TLV format
5.2.3. Adjustment Threshold
The sub-TLVs in this section are encoded to inform the PCEP peer the
adjustment threshold parameters. An implementation MAY include both
sub-TLVs for the absolute value and the percentage, in which case the
bandwidth is adjusted when either of the adjustment threshold
conditions are met.
5.2.3.1. Adjustment-Threshold sub-TLV
The Adjustment-Threshold sub-TLV is used to decide when the LSP
bandwidth should be adjusted.
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=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Adjustment Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Adjustment-Threshold sub-TLV format
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The Type is 3, Length is 4, and the value comprises of -
o Adjustment Threshold: The absolute Adjustment-Threshold bandwidth
value, 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.
If the difference between the current MaxAvgBw and the current
bandwidth reservation is greater than or equal to the threshold
value, the LSP bandwidth is adjusted to the current bandwidth
demand.
5.2.3.2. Adjustment-Threshold-Percentage sub-TLV
The Adjustment-Threshold-Percentage sub-TLV is used to decide when
the LSP bandwidth should be adjusted.
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=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Percentage |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Adjustment-Threshold-Percentage sub-TLV format
The Type is 4, Length is 4, and the value comprises of -
o Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.
o Percentage: The Adjustment-Threshold value, encoded in percentage
(an integer from 0 to 100). If the percentage difference between
the current MaxAvgBw and the current bandwidth reservation is
greater than or equal to the threshold percentage, the LSP
bandwidth is adjusted to the current bandwidth demand.
5.2.4. Minimum and Maximum Bandwidth Values
5.2.4.1. Minimum-Bandwidth sub-TLV
The Minimum-Bandwidth sub-TLV specify the minimum bandwidth allowed
for the LSP, and is expressed in bytes per second. The LSP bandwidth
cannot be adjusted below the minimum bandwidth value.
The Type is 5, Length is 4, and the value comprises of 4-octet
bandwidth value encoded in IEEE floating point format (see
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[IEEE.754.1985]), expressed in bytes per second. Refer to Section
3.1.2 of [RFC3471] for a table of commonly used values.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Minimum-Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Minimum-Bandwidth sub-TLV format
5.2.4.2. Maximum-Bandwidth sub-TLV
The Maximum-Bandwidth sub-TLV specify the maximum bandwidth allowed
for the LSP, and is expressed in bytes per second. The LSP bandwidth
cannot be adjusted above the maximum bandwidth value.
The Type is 6, Length is 4, and the value comprises of 4-octet
bandwidth value 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.
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=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Maximum-Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Maximum-Bandwidth sub-TLV format
5.2.5. Overflow and Underflow Conditions
The sub-TLVs in this section are encoded to inform the PCEP peer the
overflow and underflow threshold parameters. An implementation MAY
include sub-TLVs for the absolute value and the percentage for the
threshold, in which case the bandwidth is immediately adjusted when
either of the adjustment threshold conditions are met consecutively
for the given count.
5.2.5.1. Overflow-Threshold sub-TLV
The Overflow-Threshold sub-TLV is used to decide if the bandwidth
should be adjusted immediately.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=7 | Length=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Overflow Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Overflow-Threshold sub-TLV format
The Type is 7, Length is 8, and the value comprises of -
o Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.
o Count: The Overflow-Count value, encoded in integer. The value 0
is considered to be invalid. The number of consecutive samples
for which the overflow condition MUST be met for the LSP bandwidth
to be immediately adjusted to the current bandwidth demand,
bypassing the adjustment-interval.
o Overflow Threshold: The absolute Overflow-Threshold bandwidth
value, 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. If the
increase of the current MaxAvgBw from the current bandwidth
reservation is greater than or equal to the threshold value, the
overflow condition is met.
5.2.5.2. Overflow-Threshold-Percentage sub-TLV
The Overflow-Threshold-Percentage sub-TLV is used to decide if the
bandwidth should be adjusted immediately.
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=8 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Percentage | Reserved | Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Overflow-Threshold-Percentage sub-TLV format
The Type is 8, Length is 4, and the value comprises of -
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o Percentage: The Overflow-Threshold value, encoded in percentage
(an integer from 0 to 100). If the percentage increase of the
current MaxAvgBw from the current bandwidth reservation is greater
than or equal to the threshold percentage, the overflow condition
is met.
o Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.
o Count: The Overflow-Count value, encoded in integer. The value 0
is considered to be invalid. The number of consecutive samples
for which the overflow condition MUST be met for the LSP bandwidth
to be immediately adjusted to the current bandwidth demand,
bypassing the adjustment-interval.
5.2.5.3. Underflow-Threshold sub-TLV
The Underflow-Threshold sub-TLV is used to decide if the bandwidth
should be adjusted immediately.
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=9 | Length=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Underflow Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Underflow-Threshold sub-TLV format
The Type is 9, Length is 8, and the value comprises of -
o Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.
o Count: The Underflow-Count value, encoded in integer. The value 0
is considered to be invalid. The number of consecutive samples
for which the underflow condition MUST be met for the LSP
bandwidth to be immediately adjusted to the current bandwidth
demand, bypassing the adjustment-interval.
o Underflow Threshold: The absolute Underflow-Threshold bandwidth
value, 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. If the
decrease of the current MaxAvgBw from the current bandwidth
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reservation is greater than or equal to the threshold value, the
underflow condition is met.
5.2.5.4. Underflow-Threshold-Percentage sub-TLV
The Underflow-Threshold-Percentage sub-TLV is used to decide if the
bandwidth should be adjusted immediately.
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=10 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Percentage | Reserved | Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Underflow-Threshold-Percentage sub-TLV format
The Type is 10, Length is 4, and the value comprises of -
o Percentage: The Underflow-Threshold value, encoded in percentage
(an integer from 0 to 100). If the percentage decrease of the
current MaxAvgBw from the current bandwidth reservation is greater
than or equal to the threshold percentage, the underflow condition
is met.
o Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.
o Count: The Underflow-Count value, encoded in integer. The value 0
is considered to be invalid. The number of consecutive samples
for which the underflow condition MUST be met for the LSP
bandwidth to be immediately adjusted to the current bandwidth
demand, bypassing the adjustment-interval.
5.3. BANDWIDTH Object
As per [RFC5440], the BANDWIDTH object (Object-Class value 5) is
defined with two Object-Type values as following:
o Requested Bandwidth: BANDWIDTH Object-Type value is 1.
o Re-optimization Bandwidth: Bandwidth of an existing TE LSP for
which a re-optimization is requested. BANDWIDTH Object-Type value
is 2.
PCC reports the calculated bandwidth to be adjusted (MaxAvgBw) to the
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PCE using existing 'Requested Bandwidth with BANDWIDTH Object-Type as
1.
5.4. The PCInitiate Message
A PCInitiate message is a PCEP message sent by a PCE to a PCC to
trigger LSP instantiation or deletion [I.D.ietf-pce-pce-initiated-
lsp].
For the PCE-initiated LSP [I-D.ietf-pce-pce-initiated-lsp] with
Auto-Bandwidth feature enabled, AUTO-BANDWIDTH-ATTRIBUTE TLV MUST be
included in the LSPA object with the PCInitiate message. The rest of
the processing remains unchanged.
5.5. The PCRpt Message
As specified in [I.D.ietf-pce-pce-initiated-lsp], the PCC creates the
LSP using the attributes communicated by the PCE, and local values
for the unspecified parameters. After the successful instantiation
of the LSP, PCC automatically delegates the LSP to the PCE and
generates an LSP State Report (PCRpt) for the LSP.
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.
When the LSP is enabled with the Auto-Bandwidth feature, PCC SHOULD
include the BANDWIDTH object of type 1 to specify the calculated
bandwidth to be adjusted to the PCE in the PCRpt message.
The definition of the PCRpt message (see [I-D.ietf-pce-stateful-pce])
is unchanged by this document.
5.6. 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. As
described in Section 4.3 of this document, 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
auto-bandwidth adjustment. If a PCEP message related to auto-
bandwidth adjustment is received, it MUST be silently ignored.
When a PCEP speaker is overwhelmed, it SHOULD notify its peer by
sending a PCNtf message with Notification Type = TBD3 (Auto-bandwidth
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Overwhelm State) and Notification Value = 1 (Entering auto-bandwidth
overwhelm state). Optionally, OVERLOADED-DURATION TLV [RFC5440] MAY
be included that specifies the time period during which no further
PCEP messages related to auto-bandwidth adjustment should be sent.
When the PCEP speaker is no longer in the overwhelm state and is
available to process the auto-bandwidth adjustment, it SHOULD notify
its peer by sending a PCNtf message with Notification Type = TBD3
(Auto-bandwidth Overwhelm State) and Notification Value = 2 (Clearing
auto-bandwidth overwhelm state).
When Auto-Bandwidth feature is deployed, a PCE can send this
notification to PCC when a PCC is reporting frequent auto-bandwidth
adjustments. If a PCC is overwhelmed with re-signaling/re-routing,
it can also notify the PCE to not adjust the LSP bandwidth while in
overwhelm state.
5.7. The PCUpd Message
A PCUpd message is a PCEP message sent by a PCE to a PCC to update
the LSP parameters [I-D.ietf-pce-stateful-pce].
For the LSPs with Auto-Bandwidth feature enabled, AUTO-BANDWIDTH-
ATTRIBUTE TLV MUST be included in the LSPA object with the PCUpd
message. The PCE can use this TLV to direct the PCC to change the
auto bandwidth parameters. The rest of the processing remains
unchanged.
The definition of the PCUpd message (see [I-D.ietf-pce-stateful-pce])
is unchanged by this document.
6. Security Considerations
This document defines AUTO-BANDWIDTH-CAPABILITY TLV,
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
auto-bandwidth information as extra sensitive and could be used to
influence path computation and 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 [I-D.ietf-pce-pceps].
7. Manageability Considerations
7.1. Control of Function and Policy
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The Auto-Bandwidth feature SHOULD be controlled per tunnel (at
ingress (PCC) or PCE), the values for parameters like sample-
interval, adjustment-interval, minimum-bandwidth, maximum-bandwidth,
adjustment-threshold SHOULD be configurable by an operator.
7.2. Information and Data Models
A Management Information Base (MIB) module for modeling PCEP is
described in [RFC7420]. However, the preferred mechanism for
configuration is through a YANG model [I-D.ietf-pce-pcep-yang]. This
SHOULD be enhanced to provide controls and indicators for support of
auto-bandwidth feature. Support for various configuration knobs as
well as counters of messages sent/received containing the TLVs
(defined in this document) should be added.
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 add any new requirements
on other protocols.
7.6. 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 auto-bandwidth feature, and MAY allow a
limit to be placed on the rate of messages sent by a PCEP speaker and
received from a peer related to auto-bandwidth. It MAY also allow
sending a notification when the PCEP speaker is overwhelmed or a rate
threshold is reached.
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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.
<http://www.iana.org/assignments/pcep/pcep.xhtml#pcep-tlv-type-
indicators>.
Value Name Reference
--------------------------------------------------------------
TBD2 AUTO-BANDWIDTH-CAPABILITY [This I.D.]
TBD1 AUTO-BANDWIDTH-ATTRIBUTE [This I.D.]
8.2. AUTO-BANDWIDTH-CAPABILITY TLV Flag Field
IANA is requested to create a registry to manage the Flag field of
the AUTO-BANDWIDTH-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
No bit is defined for the AUTO-BANDWIDTH-CAPABILITY TLV Object flag
field in this document.
8.3. AUTO-BANDWIDTH-ATTRIBUTE Sub-TLV
This document specifies the AUTO-BANDWIDTH-ATTRIBUTE Sub-TLVs. IANA
is requested to create an "AUTO-BANDWIDTH-ATTRIBUTE Sub-TLV Types"
sub-registry in the "PCEP TLV Type Indicators" for the sub-TLVs
carried in the AUTO-BANDWIDTH-ATTRIBUTE TLV. New sub-TLV are
allocated only by an IETF Review action [RFC5226].
This document defines the following types:
Type Name Reference
--------------------------------------------------------------
0 Reserved [This I.D.]
1 Sample-Interval sub-TLV [This I.D.]
2 Adjustment-Interval sub-TLV [This I.D.]
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3 Adjustment-Threshold sub-TLV [This I.D.]
4 Adjustment-Threshold-Percentage sub-TLV [This I.D.]
5 Minimum-Bandwidth sub-TLV [This I.D.]
6 Maximum-Bandwidth sub-TLV [This I.D.]
7 Overflow-Threshold sub-TLV [This I.D.]
8 Overflow-Threshold-Percentage sub-TLV [This I.D.]
9 Underflow-Threshold sub-TLV [This I.D.]
10 Underflow-Threshold-Percentage sub-TLV [This I.D.]
11- Unassigned [This I.D.]
65535
8.4. Error Object
This document defines a new Error-Value for PCErr message of type 19
(Invalid Operation) [I-D.ietf-pce-stateful-pce]); IANA is requested
to make the following allocation from this registry.
<http://www.iana.org/assignments/pcep/pcep.xhtml#pcep-error-object>
Error-Value Meaning Reference
--------------------------------------------------------------
TBD4 Auto-Bandwidth Capability [This I.D.]
was not Advertised
8.5. Notification Object
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
---------------------------------------------------------------
TBD3 Auto-Bandwidth Overwhelm State [This I.D.]
Notification-value=1: Entering Auto-Bandwidth
overwhelm state
Notification-value=2: Clearing Auto-Bandwidth
overwhelm state
9. References
9.1. 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,
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May 2008.
[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 (work in progress).
[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 (work in progress).
9.2. Informative References
[RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Functional Description", RFC 3471,
January 2003.
[RFC5925] Touch, J., Mankin, A., and R. Bonica, "The TCP
Authentication Option", RFC 5925, June 2010.
[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.
[RFC8051] Zhang, X. and I. Minei, "Applicability of a Stateful Path
Computation Element (PCE)", RFC 8051, January 2017.
[I-D.ietf-pce-pceps] Lopez, D., Dios, O., Wu, W., and D. Dhody,
"Secure Transport for PCEP", draft-ietf-pce-pceps (work in
progress).
[I-D.ietf-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), October 2016.
[I-D.gandhi-pce-pm] Gandhi, R., Wen, B., Barth, C., and D. Dhody
"PCEP Extensions for Reporting MPLS-TE LSP Performance
Measurements", draft-gandhi-pce-pm (work in progress),
November 2016
[IEEE.754.1985] Institute of Electrical and Electronics Engineers,
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"Standard for Binary Floating-Point Arithmetic", IEEE
Standard 754, August 1985.
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Acknowledgments
Authors would like to thank Robert Varga, Venugopal Reddy, Reeja
Paul, Sandeep Boina, Avantika, JP Vasseur, Himanshu Shah and Adrian
Farrel for their useful comments and suggestions.
Contributors' 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
USA
Phone: +1 972 509 5599 x2240
Fax: +1 469 229 5397
EMail: leeyoung@huawei.com
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Authors' Addresses
Dhruv Dhody
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560066
India
EMail: dhruv.ietf@gmail.com
Udayasree Palle
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560037
India
EMail: udayasree.palle@huawei.com
Ravi Singh
Juniper Networks
1194 N. Mathilda Ave.
Sunnyvale, CA 94089
USA
EMail: ravis@juniper.net
Rakesh Gandhi
Individual Contributor
EMail: rgandhi.ietf@gmail.com
Luyuan Fang
eBay
USA
EMail: luyuanf@gmail.com
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