PCE Working Group D. Dhody
Internet-Draft U. Palle
Intended status: Standards Track Huawei Technologies
Expires: December 18, 2015 R. Singh
Juniper Networks
R. Gandhi
Cisco Systems, Inc.
June 16, 2015
PCEP Extensions for MPLS-TE LSP Automatic Bandwidth Adjustment with
Stateful PCE
draft-dhody-pce-stateful-pce-auto-bandwidth-05
Abstract
The Path Computation Element Communication Protocol (PCEP) provides
mechanisms for Path Computation Elements (PCEs) to perform path
computations in response to Path Computation Clients (PCCs) requests.
The stateful PCE extensions provide stateful control of Multi-
Protocol Label Switching (MPLS) Traffic Engineering Label Switched
Paths (TE LSPs) via PCEP, for the case where PCC delegates control
over one or more locally configured LSPs to the PCE.
This document describes automatic bandwidth adjustment of such LSPs
when employing an Active Stateful PCE. In one of the models
described, PCC computes the bandwidth to be adjusted and informs the
PCE whereas in the second model, PCC reports the real-time traffic to
a PCE and the PCE computes the adjustment bandwidth.
This document also describes automatic bandwidth adjustment for
stateful PCE-initiated LSPs.
Status of This Memo
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This Internet-Draft will expire on December 18, 2015.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 5
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 5
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
3. Requirements for PCEP Extensions . . . . . . . . . . . . . . 5
4. Architectural Overview . . . . . . . . . . . . . . . . . . . 7
4.1. Auto-Bandwidth Overview . . . . . . . . . . . . . . . . . 7
4.2. Theory of Operation . . . . . . . . . . . . . . . . . . . 9
4.3. Scaling Considerations . . . . . . . . . . . . . . . . . 10
5. Extensions to the PCEP . . . . . . . . . . . . . . . . . . . 10
5.1. AUTO-BANDWIDTH-ATTRIBUTE TLV . . . . . . . . . . . . . . 10
5.1.1. Adjustment Parameters . . . . . . . . . . . . . . . . 12
5.1.1.1. Sample-Interval sub-TLV . . . . . . . . . . . . . 12
5.1.1.2. Adjustment-Interval sub-TLV . . . . . . . . . . . 13
5.1.1.3. Adjustment Threshold . . . . . . . . . . . . . . 13
5.1.1.4. Minimum and Maximum Bandwidth . . . . . . . . . . 14
5.1.1.5. Overflow and Underflow Condition . . . . . . . . 15
5.1.2. Real-time Traffic Reporting . . . . . . . . . . . . . 18
5.1.2.1. Real-time-Traffic-Report-Interval sub-TLV . . . . 19
5.1.2.2. Real-time-Traffic-Report-Threshold sub-TLV . . . 19
5.1.2.3. Real-time-Traffic-Report-Threshold-Percentage
sub-TLV . . . . . . . . . . . . . . . . . . . . . 20
5.1.2.4. Real-time-Traffic-Report-Flow-Threshold sub-TLV . 20
5.1.2.5. Real-time-Traffic-Report-Flow-Threshold-
Percentage sub-TLV . . . . . . . . . . . . . . . 21
5.2. BANDWIDTH Object . . . . . . . . . . . . . . . . . . . . 22
5.2.1. Auto-Bandwidth Adjusted Bandwidth . . . . . . . . . . 22
5.2.2. Bandwidth-Usage Report . . . . . . . . . . . . . . . 22
5.3. The PCRpt Message . . . . . . . . . . . . . . . . . . . . 23
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5.4. The PCInitiate Message . . . . . . . . . . . . . . . . . 23
6. Security Considerations . . . . . . . . . . . . . . . . . . . 23
7. Manageability Considerations . . . . . . . . . . . . . . . . 23
7.1. Control of Function and Policy . . . . . . . . . . . . . 23
7.2. Information and Data Models . . . . . . . . . . . . . . . 24
7.3. Liveness Detection and Monitoring . . . . . . . . . . . . 24
7.4. Verify Correct Operations . . . . . . . . . . . . . . . . 24
7.5. Requirements On Other Protocols . . . . . . . . . . . . . 24
7.6. Impact On Network Operations . . . . . . . . . . . . . . 24
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24
8.1. PCEP TLV Type Indicators . . . . . . . . . . . . . . . . 24
8.2. AUTO-BANDWIDTH-ATTRIBUTE Sub-TLV . . . . . . . . . . . . 24
8.3. BANDWIDTH Object . . . . . . . . . . . . . . . . . . . . 25
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 25
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 25
10.1. Normative References . . . . . . . . . . . . . . . . . . 25
10.2. Informative References . . . . . . . . . . . . . . . . . 26
Appendix A. Contributor Addresses . . . . . . . . . . . . . . . 27
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27
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 under 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
referred to as Auto-Bandwidth.
Enabling Auto-Bandwidth feature on an LSP results in the LSP
automatically adjusting its bandwidth based on the actual traffic
flowing through the LSP. An LSP set-up with some arbitrary
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(including zero) bandwidth value, automatically monitors the traffic
flow and adjusts its bandwidth every adjustment-interval period. The
bandwidth adjustment uses the make-before-break signaling method so
that there is no interruption to traffic flow. This is described in
detail in Section 4.1. [I-D.ietf-pce-stateful-pce-app] describes the
use-case for Auto-Bandwidth adjustment for passive and active
stateful PCE.
In this document, following deployment models are considered for
employing Auto-Bandwidth feature with active stateful PCE.
o Deployment model 1: PCC to decide adjusted bandwidth:
* In this model, the PCC (head-end of the LSP) monitors and
calculates the new adjusted bandwidth. The PCC reports the
calculated bandwidth to be adjusted to the PCE.
* This approach would be similar to 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.
* For PCE-initiated LSP, the PCC is requested during the LSP
initiation to monitor and calculate the new adjusted bandwidth.
o Deployment model 2: PCE to decide adjusted bandwidth:
* In this model, the PCE calculates the new adjusted bandwidth
for the LSP.
* Active stateful PCE can use information such as historical
trending data, application-specific information about expected
demands and central policy information along with real-time
actual flow volumes to make smarter bandwidth adjustment to the
delegated LSPs. Since the LSP has delegated control to the
PCE, it is inherently suited that it should be the stateful PCE
that decides the bandwidth adjustments.
* For PCE-initiated LSP, the PCC is requested during initiation,
to monitor and report the real-time bandwidth usage.
* This model does not exclude use of any other mechanism employed
by stateful PCE to learn real-time traffic information. But at
the same time, using the same protocol (PCEP in this case) for
updating and reporting the adjustment parameters as well as to
learn real-time bandwidth usage is operationally beneficial.
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This document defines extensions needed to support Auto-Bandwidth
feature on the LSPs in a active stateful PCE model using PCEP.
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.
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
There are two deployment models considered in this document for
automatic bandwidth adjustments in case of active stateful PCE. In
the model where PCC decides the adjusted bandwidth, PCC can report
the new requested bandwidth and an active stateful PCE can update the
bandwidth for a delegated LSP via existing mechanisms defined in
[I-D.ietf-pce-stateful-pce]. Additional PCEP extensions required are
summarized in the following table.
+--------+----------------------------+-----------------------------+
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| Model | PCC Initiated | PCE Initiated |
+--------+----------------------------+-----------------------------+
| | | |
| PCC to | PCC monitors the traffic | At the time of initiation, |
| decide | and reports the calculated | PCE request PCC to monitor |
| adjust | bandwidth to be adjusted | the traffic and reports the |
| ed ban | to the PCE. | calculated bandwidth to be |
| dwidth | | adjusted to the PCE. |
| | | |
| | No new extensions are | Extension is needed for PCE |
| | needed. | to pass on the adjustment |
| | | parameters at the time of |
| | | Initiation. |
| | | |
| | Optionally AUTO-BANDWIDTH- | Refer the AUTO-BANDWIDTH- |
| | ATTRIBUTE TLV can be used | ATTRIBUTE TLV (and sub-TLVs |
| | to identify the LSP with | e.g. Adjustment-Interval, |
| | Auto-Bandwidth Feature | Minimum-Bandwidth) in |
| | enabled. | Section 5.1. |
| | | |
| ------ | -------------------------- | --------------------------- |
| | | |
| PCC re | PCC monitors the traffic | At the time of initiation, |
| ports | and reports the real-time | PCE request PCC to monitor |
| real- | traffic to the PCE. It is | the traffic and reports the |
| time t | PCE that decides the | real-time traffic to the |
| raffic | calculated bandwidth to be | PCE. It is PCE that decides |
| and | adjusted and updates the | the calculated bandwidth to |
| PCE to | LSP accordingly. | be adjusted and updates the |
| decide | | LSP accordingly. |
| adjust | | |
| ed ban | | |
| dwidth | | |
| | | |
| | Extension is needed for | Extension is needed for PCE |
| | PCC to pass on the | to pass on the real-time |
| | adjustment parameters at | traffic reporting |
| | the time of delegation to | parameters at the time of |
| | PCE. | Initiation. |
| | | |
| | Refer the AUTO-BANDWIDTH- | Refer the Real-time Traffic |
| | ATTRIBUTE TLV (and sub- | Reporting (e.g. Real-time- |
| | TLVs e.g. Adjustment- | Traffic-Report-Interval, |
| | Threshold, Real-time- | Real-time-Traffic-Report- |
| | Traffic-Report-Interval) | Threshold) in Section |
| | in Section 5.1. | 5.1.2. |
| | | |
| | Further extension to | Further extension to report |
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| | report the real-time | the real-time traffic to |
| | traffic to PCE are also | PCE are also needed (Refer |
| | needed (Refer Bandwidth- | Bandwidth-Usage type in |
| | Usage type in Section | Section 5.2.2). |
| | 5.2.2). | |
| | | |
+--------+----------------------------+-----------------------------+
Table 1: Auto-Bandwidth Deployment Models
Additional Auto-Bandwidth deployment considerations are summarized
below:
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 traffic but be constant as set by the operator.
o It is also required to identify and inform the PCEP peer the model
of operation i.e. if PCC decides the adjusted bandwidth, or PCC
reports the real-time traffic instead and the PCE decides the
adjusted bandwidth.
* Note that PCEP extension for reporting real-time traffic, as
specified in this document, is one of the ways for a PCE to
learn this information. But at the same time a stateful PCE
may choose to learn this information from other means like
management, performance tools, which are beyond the scope of
this document.
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 an LSP to automatically and dynamically
adjust its reserved bandwidth over time, i.e. without network
operator intervention. The bandwidth adjustment uses the make-
before-break 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
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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 demand during a time interval.
This is the maximum value of the averaged traffic 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.
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-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
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bandwidth demand bypassing the adjustment- interval if the
overflow-condition is met consecutively for the overflow-counts.
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-counts.
Report-Interval: This value indicates the periodic interval when the
collected real-time traffic bandwidth samples (BwSample) should be
reported to the stateful PCE via the PCRpt message.
Report-Threshold: This value is used to decide if the real-time
traffic bandwidth samples collected should be reported. Only if
the percentage or the absolute difference between at least one of
the bandwidth samples collected and the current bandwidth
reservation is greater than or equal to the threshold value, the
bandwidth samples collected during the Report-Interval are
reported otherwise the bandwidth sample(s) are skipped.
Report-Flow-Threshold: This value is used to decide when the real-
time traffic bandwidth samples should be reported immediately when
there is a sudden change in traffic demand. If the percentage or
absolute difference between the current bandwidth sample and the
current bandwidth reservation is greater than or equal to the flow
threshold value, all the bandwidth samples collected so far are
reported to the PCE immediately.
4.2. 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 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 PCEP
peer which 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
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(percentage or absolute value), the LSP bandwidth is adjusted to the
current bandwidth demand (MaxAvgBw).
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.
In case of Deployment model 2, the PCC reports the real-time traffic
information and the PCE decides the adjusted bandwidth. Multiple
bandwidth samples are collected every report-interval, and reported
together to the PCE. To avoid reporting minor changes in real-time
traffic, report-threshold is used, to suppress the sending of the
collected samples during the report-interval. The collected samples
are reported if at least one sample crosses the Report-Threshold
(percentage or absolute value). In order to accommodate sudden
changes in the real-time traffic, report flow threshold is employed
by pre-maturely expiry of the report-interval to report the
unreported bandwidth samples collected so far.
All thresholds in this document could be represented in both absolute
value and percentage, and could be used together.
4.3. Scaling Considerations
There are potential scaling concerns for the model where PCC (ingress
LSR) reports real-time traffic information to the stateful PCE for a
large number of LSPs. It is recommended to combine multiple
bandwidth samples (BwSample) using larger report-interval and report
them together to the PCE, thus reducing the number of PCRpt messages.
Further Report-Threshold can be use to skip reporting the bandwidth
samples for small changes in the bandwidth.
The processing cost of monitoring a large number of LSPs at the PCC
and handling bandwidth change requests at PCE should be taken into
consideration. Note that, this will be implementation dependent.
5. Extensions to the PCEP
5.1. AUTO-BANDWIDTH-ATTRIBUTE TLV
The AUTO-BANDWIDTH-ATTRIBUTE TLV can be included as an optional TLV
in the LSPA object (as described in [RFC5440]). Whenever the LSP
with Auto-Bandwidth feature enabled is delegated, AUTO-BANDWIDTH-
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ATTRIBUTE TLV is carried in PCRpt message in LSPA object. The TLV
provides PCE with the 'configurable knobs' of this feature. In case
of PCE-Initiated LSP ([I-D.ietf-pce-pce-initiated-lsp]) with Auto-
Bandwidth feature enabled, this TLV is included in LSPA object with
PCInitiate message.
The format of the AUTO-BANDWIDTH-ATTRIBUTE TLV is shown in the
following figure:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=[TBD] | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// sub-TLVs //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
AUTO-BANDWIDTH-ATTRIBUTE TLV format
Type: TBD
Length: Variable
Value: This comprises one or more sub-TLVs.
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
11 4 Real-time-Traffic-Report-Interval sub-TLV
12 4 Real-time-Traffic-Report-Threshold sub-TLV
13 4 Real-time-Traffic-Report-Threshold-Percentage sub-TLV
14 4 Real-time-Traffic-Report-Flow-Threshold sub-TLV
15 4 Real-time-Traffic-Report-Flow-Threshold-Percentage sub-TLV
Future specification can define additional sub-TLVs.
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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 any others MUST be ignored.
If the sub-TLV are not encoded, the defaults based on the local
policy are assumed.
The following sub-sections describe the sub-TLVs which are currently
defined to be carried within the AUTO-BANDWIDTH-ATTRIBUTE TLV.
5.1.1. Adjustment Parameters
The sub-TLVs in this section are encoded to inform the PCEP peer the
various sampling and adjustment parameters, and serves the following
purpose -
o For PCE-Initiated LSPs inform the PCC of the various sampling and
adjustment parameters.
o For PCC-Initiated LSPs in the Deployment Model 2 (where PCE
decides the adjusted bandwidth), inform the PCE of the various
sampling and adjustment parameters.
5.1.1.1. 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.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sample-Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Sample-Interval sub-TLV format
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5.1.1.2. 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.
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
5.1.1.3. 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.
5.1.1.3.1. 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
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.
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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.
5.1.1.3.2. 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.
5.1.1.4. Minimum and Maximum Bandwidth
5.1.1.4.1. 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
[IEEE.754.1985]), expressed in bytes per second. Refer to
Section 3.1.2 of [RFC3471] for a table of commonly used values.
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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=5 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Minimum-Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Minimum-Bandwidth sub-TLV format
5.1.1.4.2. 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
5.1.1.5. Overflow and Underflow Condition
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.
5.1.1.5.1. 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 4, 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.
5.1.1.5.2. 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.
5.1.1.5.3. 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.
5.1.1.5.4. 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.
5.1.2. Real-time Traffic Reporting
The sub-TLVs in this section are encoded to inform the PCEP peer the
various real-time traffic reporting parameters in the Deployment
Model 2 (where PCE decides the adjusted bandwidth). In this model,
Real-time-Traffic-Report-Interval sub-TLV MUST be included to specify
the frequency of reporting.
The report threshold is used to decide if the collected bandwidth
samples should be reported or skipped. An implementation MAY include
both sub-TLVs for the absolute value and the percentage, in which
case the real-time traffic is reported when either of the report
threshold conditions are met.
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The report flow threshold is used to decide when the collected
bandwidth samples should be reported immediately, bypassing the
report interval. An implementation MAY include both sub-TLVs for the
absolute value and the percentage, in which case the real-time
traffic is reported immediately when either of the report flow
threshold conditions are met.
5.1.2.1. Real-time-Traffic-Report-Interval sub-TLV
The Real-time-Traffic-Report-Interval sub-TLV specifies a time
interval in seconds in which collected bandwidth samples should be
reported to PCE.
The Type is 11, Length is 4, and the value comprises of 4-octet time
interval, the valid range is from 1 to 604800, in 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=11 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Real-time-Traffic-Report-Interval |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Real-time-Traffic-Report-Interval sub-TLV format
There is no default value. This sub-TLV MUST be included to enable
the real-time traffic reporting.
5.1.2.2. Real-time-Traffic-Report-Threshold sub-TLV
The Real-time-Traffic-Report-Threshold sub-TLV is used to decide when
the bandwidth samples collected should be reported immediately,
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=12 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Real-time-Traffic-Report Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Real-time-Traffic-Report-Threshold sub-TLV format
The Type is 12, Length is 4, and the value comprises of -
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o Threshold: The absolute 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 or the decrease of at least
one of the bandwidth samples (BwSample) collected so far compared
to the current bandwidth reservation is greater than or equal to
the threshold value, the bandwidth samples collected so far are
reported.
5.1.2.3. Real-time-Traffic-Report-Threshold-Percentage sub-TLV
The Real-time-Traffic-Report-Threshold sub-TLV is used to decide when
the bandwidth samples collected should be reported immediately,
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=13 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Percentage |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Real-time-Traffic-Report-Threshold-Percentage sub-TLV format
The Type is 13, 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 threshold value, encoded in percentage (an integer
from 0 to 100). If the percentage increase or the decrease of at
least one of the bandwidth sample (BwSample) compared to the
current bandwidth reservation is greater than or equal to the
threshold percentage, the bandwidth samples collected so far are
reported.
5.1.2.4. Real-time-Traffic-Report-Flow-Threshold sub-TLV
The Real-time-Traffic-Report-Flow-Threshold sub-TLV is used to decide
when the bandwidth samples collected should be reported immediately,
bypassing the report-interval.
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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=14 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Real-time-Traffic-Report-Flow Threshold |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Real-time-Traffic-Report-Flow-Threshold sub-TLV format
The Type is 14, Length is 4, and the value comprises of -
o Threshold: The absolute flow 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 or the decrease of the
current bandwidth sample (BwSample) compared to the current
bandwidth reservation is greater than or equal to the flow
threshold value, all the bandwidth samples collected so far are
reported immediately, bypassing the report-interval.
5.1.2.5. Real-time-Traffic-Report-Flow-Threshold-Percentage sub-TLV
The Real-time-Traffic-Report-Flow-Threshold sub-TLV is used to decide
when the bandwidth samples collected should be reported immediately,
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=15 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Percentage |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Real-time-Traffic-Report-Flow-Threshold-Percentage sub-TLV format
The Type is 15, 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 flow threshold value, encoded in percentage (an
integer from 0 to 100). If the percentage increase or the
decrease of the current bandwidth sample (BwSample) compared to
the current bandwidth reservation is greater than or equal to the
threshold percentage, all the bandwidth samples collected so far
are reported immediately, bypassing the report-interval.
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5.2. BANDWIDTH Object
5.2.1. Auto-Bandwidth Adjusted Bandwidth
As per [RFC5440], the BANDWIDTH object is defined with two Object-
Type values as following:
o Requested Bandwidth: BANDWIDTH Object-Type is 1.
o Re-optimization Bandwidth: Bandwidth of an existing TE LSP for
which a re-optimization is requested. BANDWIDTH Object-Type is 2.
In the first model, where PCC calculates the adjusted bandwidth, PCC
only reports the calculated bandwidth to be adjusted (MaxAvgBw) to
the PCE. This is done via the existing 'Requested Bandwidth with
BANDWIDTH Object-Type as 1'.
5.2.2. Bandwidth-Usage Report
A new BANDWIDTH object type is defined to report the actual bandwidth
usage of a TE LSP.
The Object type is [TBD], the object body has a variable length,
multiples of 4 bytes. The payload format is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BwSample1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BwSampleN |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Bandwidth-Usage format
o BwSample: The actual bandwidth usage, (the BwSample collected at
the end of each sample-interval) encoded in IEEE floating point
format (see [IEEE.754.1985]), expressed in bytes per second.
The Bandwidth-Usage object can be used in the second deployment model
where PCC reports the TE LSP bandwidth usage and the PCE decides the
auto-bandwidth adjusted bandwidth.
The Bandwidth-Usage object can also be used for TE LSPs without
enabling the auto-bandwidth feature, to learn the actual bandwidth
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usage of the LSPs for other applications at the stateful PCE. The
details of which are beyond the scope of this document.
5.3. The PCRpt Message
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, and Real-
time-Traffic-Report-Interval sub-TLV is not present (Deployment model
1), PCC SHOULD include the BANDWIDTH object of type 1 to specify the
calculated bandwidth to be adjusted to the PCE in the PCRpt message.
When the LSP is enabled with the Auto-Bandwidth feature, and Real-
time-Traffic-Report-Interval sub-TLV is present (Deployment model 2),
PCC SHOULD include the BANDWIDTH object of type [TBD] to report the
real-time traffic 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.
5.4. The PCInitiate Message
For PCE-initiated LSP [I-D.ietf-pce-pce-initiated-lsp] with Auto-
Bandwidth feature enabled, AUTO-BANDWIDTH-ATTRIBUTE TLV MUST be
included in LSPA object with the PCInitiate message. The rest of the
processing remains unchanged.
6. Security Considerations
This document defines a new BANDWIDTH type and AUTO-BANDWIDTH-
ATTRIBUTE TLV which do 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 reporting of the real-time traffic
information as extra sensitive and thus should employ suitable PCEP
security mechanisms like TCP-AO or [I-D.ietf-pce-pceps].
7. Manageability Considerations
7.1. Control of Function and Policy
The Auto-Bandwidth feature MUST BE controlled per tunnel (at Ingress
(PCC) or PCE), the values for parameters like sample-interval,
adjustment- interval, minimum-bandwidth, maximum-bandwidth,
adjustment-threshold, report-interval, report-threshold SHOULD be
configurable by an operator.
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7.2. Information and Data Models
[RFC7420] describes the PCEP MIB, there are no new MIB Objects for
this document.
7.3. Liveness Detection and Monitoring
Mechanisms defined in this document do not imply any new liveness
detection and monitoring requirements in addition to those already
listed in [RFC5440].
7.4. Verify Correct Operations
Mechanisms defined in this document do not imply any new operation
verification requirements in addition to those already listed in
[RFC5440].
7.5. Requirements On Other Protocols
Mechanisms defined in this document do not imply any new requirements
on other protocols.
7.6. Impact On Network Operations
Mechanisms defined in this document do not have any impact on network
operations in addition to those already listed in [RFC5440].
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
TBD AUTO-BANDWIDTH-ATTRIBUTE [This I.D.]
8.2. 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. This document defines
the following types:
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Type Name Reference
--------------------------------------------------------------
0 Reserved [This I.D.]
1 Sample-Interval sub-TLV [This I.D.]
2 Adjustment-Interval sub-TLV [This I.D.]
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 Real-time-Traffic-Report-Interval sub-TLV [This I.D.]
12 Real-time-Traffic-Report-Threshold sub-TLV [This I.D.]
13 Real-time-Traffic-Report-Threshold-Percentage [This I.D.]
sub-TLV
14 Real-time-Traffic-Report-Flow-Threshold [This I.D.]
sub-TLV
15 Real-time-Traffic-Report-Flow-Threshold [This I.D.]
-Percentage sub-TLV
16- Unassigned [This I.D.]
65535
8.3. BANDWIDTH Object
This document defines new object type for the BANDWIDTH object; IANA
is requested to make the following allocations from this registry.
http://www.iana.org/assignments/pcep/pcep.xhtml#pcep-objects
Object-Class Value Name Reference
5 BANDWIDTH [This I.D.]
Object-Type
TBD: Bandwidth-Usage Report
9. Acknowledgments
We would like to thank Venugopal Reddy, Reeja Paul, Sandeep Boina and
Avantika for their useful comments and suggestions.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
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[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-11 (work in progress), April 2015.
[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-04 (work in
progress), April 2015.
[IEEE.754.1985]
Institute of Electrical and Electronics Engineers,
"Standard for Binary Floating-Point Arithmetic", IEEE
Standard 754, August 1985.
10.2. Informative References
[RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Functional Description", RFC 3471,
January 2003.
[RFC7420] Koushik, A., Stephan, E., Zhao, Q., King, D., and J.
Hardwick, "Path Computation Element Communication Protocol
(PCEP) Management Information Base (MIB) Module", RFC
7420, December 2014.
[I-D.ietf-pce-stateful-pce-app]
Zhang, X. and I. Minei, "Applicability of a Stateful Path
Computation Element (PCE)", draft-ietf-pce-stateful-pce-
app-04 (work in progress), April 2015.
[I-D.ietf-pce-pceps]
Lopez, D., Dios, O., Wu, W., and D. Dhody, "Secure
Transport for PCEP", draft-ietf-pce-pceps-04 (work in
progress), May 2015.
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Appendix A. Contributor Addresses
He Zekun
Tencent Holdings Ltd,
Shenzhen P.R.China
Email: kinghe@tencent.com
Xian Zhang
Huawei Technologies
Research Area F3-1B,
Huawei Industrial Base,
Shenzhen, 518129, China
Phone: +86-755-28972645
Email: zhang.xian@huawei.com
Young Lee
Huawei Technologies
1700 Alma Drive, Suite 100
Plano, TX 75075
USA
Phone: +1 972 509 5599 x2240
Fax: +1 469 229 5397
EMail: leeyoung@huawei.com
Authors' Addresses
Dhruv Dhody
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560037
India
EMail: dhruv.ietf@gmail.com
Udayasree Palle
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560037
India
EMail: udayasree.palle@huawei.com
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Ravi Singh
Juniper Networks
1194 N. Mathilda Ave.
Sunnyvale, CA 94089
USA
EMail: ravis@juniper.net
Rakesh Gandhi
Cisco Systems, Inc.
EMail: rgandhi@cisco.com
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