One document matched: draft-dhody-pce-stateful-pce-auto-bandwidth-05.xml
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<front>
<title abbrev="AUTO-BW for Stateful PCE">PCEP Extensions for MPLS-TE LSP Automatic Bandwidth Adjustment with Stateful PCE</title>
<author initials="D" surname="Dhody" fullname="Dhruv Dhody">
<organization>Huawei Technologies</organization>
<address>
<postal>
<street>Divyashree Techno Park, Whitefield</street>
<city>Bangalore</city>
<region>Karnataka</region>
<code>560037</code>
<country>India</country>
</postal>
<email>dhruv.ietf@gmail.com</email>
</address>
</author>
<author initials="U" surname="Palle" fullname="Udayasree Palle">
<organization>Huawei Technologies</organization>
<address>
<postal>
<street>Divyashree Techno Park, Whitefield</street>
<city>Bangalore</city>
<region>Karnataka</region>
<code>560037</code>
<country>India</country>
</postal>
<email>udayasree.palle@huawei.com</email>
</address>
</author>
<author initials="R" surname="Singh" fullname="Ravi Singh">
<organization>Juniper Networks</organization>
<address>
<postal>
<street>1194 N. Mathilda Ave.</street>
<city>Sunnyvale</city>
<region>CA</region>
<code>94089</code>
<country>USA</country>
</postal>
<email>ravis@juniper.net</email>
</address>
</author>
<author initials="R" surname="Gandhi" fullname="Rakesh Gandhi">
<organization>Cisco Systems, Inc.</organization>
<address>
<postal>
<street></street>
<city></city>
<region></region>
<code></code>
<country></country>
</postal>
<email>rgandhi@cisco.com</email>
</address>
</author>
<date month="June" year="2015" />
<area>Routing</area>
<workgroup>PCE Working Group</workgroup>
<abstract>
<t>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.</t>
<t>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.</t>
<t>This document also describes automatic bandwidth adjustment for
stateful PCE-initiated LSPs.</t>
</abstract>
</front>
<middle>
<section title="Introduction" toc="default">
<t><xref target="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).</t>
<t><xref target='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
<xref target='I-D.ietf-pce-pce-initiated-lsp'/> describes the setup,
maintenance and teardown of PCE-initiated LSPs under the stateful
PCE model.</t>
<t>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.</t>
<t>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
(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 <xref target="sec_auto"/>.
<xref target='I-D.ietf-pce-stateful-pce-app'/> describes the
use-case for Auto-Bandwidth adjustment for passive and active
stateful PCE.</t>
<t>In this document, following deployment models are considered for
employing Auto-Bandwidth feature with active stateful PCE.
<list style="symbols">
<t>Deployment model 1: PCC to decide adjusted bandwidth:
<list style="symbols">
<t>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.</t>
<t>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.</t>
<t>For PCE-initiated LSP, the PCC is requested during the LSP
initiation to monitor and calculate the new adjusted bandwidth.</t>
</list></t>
<t>Deployment model 2: PCE to decide adjusted bandwidth:
<list style="symbols">
<t>In this model, the PCE calculates the new adjusted bandwidth for
the LSP.</t>
<t>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. </t>
<t>For PCE-initiated LSP, the PCC is requested during initiation, to
monitor and report the real-time bandwidth usage.</t>
<t>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.</t>
</list>
</t>
</list>
</t>
<t>This document defines extensions needed to support Auto-Bandwidth
feature on the LSPs in a active stateful PCE model using PCEP.</t>
</section>
<section title="Conventions Used in This Document" toc="default">
<section title="Requirements Language" toc="default">
<t>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 <xref target="RFC2119"/>.</t>
</section>
<section title="Terminology" toc="default">
<t>The following terminology is used in this document.</t>
<t>
<list style="hanging">
<t hangText="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.</t>
<t hangText="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.</t>
<t hangText="PCC:">Path Computation Client. Any client application
requesting a path computation to be performed by a Path
Computation Element.</t>
<t hangText="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.</t>
<t hangText="TE LSP:">Traffic Engineering Label Switched Path.</t>
</list>
</t>
<t>Note the Auto-Bandwidth feature specific terms defined in <xref target="sec_auto"/>.</t>
</section>
</section>
<section title="Requirements for PCEP Extensions" toc="default">
<t>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
<xref target='I-D.ietf-pce-stateful-pce'/>. Additional PCEP extensions required are
summarized in the following table.</t>
<texttable anchor="tab_dep" title="Auto-Bandwidth Deployment Models" suppress-title="false" align="center" style="full">
<ttcol align="left">Model</ttcol>
<ttcol align="left">PCC Initiated</ttcol>
<ttcol align="left">PCE Initiated</ttcol>
<c></c><c></c><c></c>
<c>PCC to decide adjusted bandwidth</c>
<c>PCC monitors the traffic and reports the calculated bandwidth to be adjusted to the PCE. </c>
<c>At the time of initiation, PCE request PCC to monitor the traffic and reports the calculated bandwidth to be adjusted to the PCE. </c>
<c></c><c></c><c></c>
<c></c><c>No new extensions are needed.</c><c>Extension is needed for PCE to pass on the adjustment parameters at the time of Initiation.</c>
<c></c><c></c><c></c>
<c></c><c>Optionally AUTO-BANDWIDTH-ATTRIBUTE TLV can be used to identify the LSP with Auto-Bandwidth Feature enabled.</c><c>Refer the AUTO-BANDWIDTH-ATTRIBUTE TLV (and sub-TLVs e.g. Adjustment-Interval, Minimum-Bandwidth) in <xref target="sec_auto_tlv"/>.</c>
<c></c><c></c><c></c>
<c>------</c><c>--------------------------</c><c>---------------------------</c>
<c></c><c></c><c></c>
<c>PCC reports real-time traffic and PCE to decide adjusted bandwidth</c>
<c>PCC monitors the traffic and reports the real-time traffic to the PCE. It is PCE that decides the calculated bandwidth to be adjusted and updates the LSP accordingly. </c>
<c>At the time of initiation, PCE request PCC to monitor the traffic and reports the real-time traffic to the PCE. It is PCE that decides the calculated bandwidth to be adjusted and updates the LSP accordingly.</c>
<c></c><c></c><c></c>
<c></c><c>Extension is needed for PCC to pass on the adjustment parameters at the time of delegation to PCE.</c><c>Extension is needed for PCE to pass on the real-time traffic reporting parameters at the time of Initiation.</c>
<c></c><c></c><c></c>
<c></c><c>Refer the AUTO-BANDWIDTH-ATTRIBUTE TLV (and sub-TLVs e.g. Adjustment-Threshold, Real-time-Traffic-Report-Interval) in <xref target="sec_auto_tlv"/>.</c><c>Refer the Real-time Traffic Reporting (e.g. Real-time-Traffic-Report-Interval, Real-time-Traffic-Report-Threshold) in <xref target="sec_real"/>.</c>
<c></c><c></c><c></c>
<c></c><c>Further extension to report the real-time traffic to PCE are also needed (Refer Bandwidth-Usage type in <xref target="sec_real_time_bw"/>).</c><c>Further extension to report the real-time traffic to PCE are also needed (Refer Bandwidth-Usage type in <xref target="sec_real_time_bw"/>).</c>
<c></c><c></c><c></c>
</texttable>
<t>Additional Auto-Bandwidth deployment considerations are summarized
below:</t>
<t>
<list style="symbols">
<t>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. </t>
<t>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.
<list style="symbols">
<t>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.</t>
</list>
</t>
<t>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.</t>
</list>
</t>
</section>
<section title="Architectural Overview" toc="default">
<section title="Auto-Bandwidth Overview" toc="default" anchor="sec_auto">
<t>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.</t>
<t>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. </t>
<t>Note the following definitions of the Auto-Bandwidth terms:</t>
<t>
<list style="hanging">
<t hangText="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.</t>
<t hangText="Adjusted Bandwidth:">This is the Auto-Bandwidth computed bandwidth
that needs to be adjusted for the LSP.</t>
<t hangText="Sample-Interval:">The periodic time interval at which the traffic
rate is collected as a sample.</t>
<t hangText="Bandwidth-Sample (BwSample):">The bandwidth sample collected at every
sample interval to measure the traffic rate.</t>
<t hangText="Adjustment-Interval:">The periodic time interval at which the
bandwidth adjustment should be made using the MaxAvgBw.</t>
<t hangText="Maximum-Bandwidth:">The maximum bandwidth that can be
reserved for the LSP.</t>
<t hangText="Minimum-Bandwidth:">The minimum bandwidth that can
be reserved for the LSP.</t>
<t hangText="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.</t>
<t hangText="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-counts.</t>
<t hangText="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.</t>
<t hangText="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.</t>
<t hangText="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.</t>
<t hangText="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.</t> </list>
</t>
</section>
<section title="Theory of Operation" toc="default">
<t>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. </t>
<t>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).</t>
<t>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.</t>
<t>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.</t>
<t>All thresholds in this document could be represented in both
absolute value and percentage, and could be used together.</t>
</section>
<section title="Scaling Considerations" toc="default">
<t>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.</t>
<t>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.</t>
</section>
</section>
<section title="Extensions to the PCEP" toc="default">
<section title="AUTO-BANDWIDTH-ATTRIBUTE TLV" toc="default" anchor="sec_auto_tlv">
<t>The AUTO-BANDWIDTH-ATTRIBUTE TLV can be included as an optional TLV in the
LSPA object (as described in <xref target='RFC5440'/>). Whenever the LSP
with Auto-Bandwidth feature enabled is delegated,
AUTO-BANDWIDTH-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 (<xref target='I-D.ietf-pce-pce-initiated-lsp'/>)
with Auto-Bandwidth feature enabled, this TLV is included in LSPA object with PCInitiate message.</t>
<t>The format of the AUTO-BANDWIDTH-ATTRIBUTE TLV is shown in the following figure:
<figure title="AUTO-BANDWIDTH-ATTRIBUTE TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure></t>
<t>Type: TBD</t>
<t>Length: Variable</t>
<t>Value: This comprises one or more sub-TLVs.</t>
<t>Following sub-TLVs are defined in this document:
<figure title="" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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
]]></artwork>
</figure> </t>
<t>Future specification can define additional sub-TLVs.</t>
<t>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.</t>
<t>If the sub-TLV are not encoded, the defaults based on the local policy are
assumed. </t>
<t>The following sub-sections describe the sub-TLVs which are currently defined to be carried
within the AUTO-BANDWIDTH-ATTRIBUTE TLV.</t>
<section title="Adjustment Parameters" toc="default">
<t>The sub-TLVs in this section are encoded to inform the PCEP peer the
various sampling and adjustment parameters, and serves the following purpose -
<list style = "symbols">
<t>For PCE-Initiated LSPs inform the PCC of the various sampling and adjustment parameters.</t>
<t>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.</t>
</list>
</t>
<section title="Sample-Interval sub-TLV" toc="default">
<t>The Sample-Interval sub-TLV specifies a time interval in seconds at
which traffic samples are collected at the PCC.</t>
<t>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.
<figure title="Sample-Interval sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
</section>
<section title="Adjustment-Interval sub-TLV" toc="default">
<t>The Adjustment-Interval sub-TLV specifies a time interval in seconds at which
bandwidth adjustment should be made.</t>
<t>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.
<figure title="Adjustment-Interval sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
</section>
<section title="Adjustment Threshold" toc="default">
<t>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.</t>
<section title="Adjustment-Threshold sub-TLV" toc="default">
<t>The Adjustment-Threshold sub-TLV is used to decide when the LSP
bandwidth should be adjusted.
<figure title="Adjustment-Threshold sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>The Type is 3, Length is 4,
and the value comprises of -
<list style = "symbols">
<t>Adjustment Threshold:
The absolute Adjustment-Threshold bandwidth value,
encoded in IEEE floating point format (see
<xref target="IEEE.754.1985"/>), expressed in bytes per second.
Refer to Section 3.1.2 of <xref target="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.</t>
</list></t>
</section>
<section title="Adjustment-Threshold-Percentage sub-TLV" toc="default">
<t> The Adjustment-Threshold-Percentage sub-TLV is used to decide when
the LSP bandwidth should be adjusted.
<figure title="Adjustment-Threshold-Percentage sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>The Type is 4, Length is 4,
and the value comprises of -
<list style = "symbols">
<t>Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.</t>
<t>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.</t>
</list></t>
</section>
</section>
<section title="Minimum and Maximum Bandwidth" toc="default">
<section title="Minimum-Bandwidth sub-TLV" toc="default">
<t>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.</t>
<t>The Type is 5, Length is 4,
and the value comprises of 4-octet bandwidth value encoded in IEEE floating point format (see
<xref target="IEEE.754.1985"/>), expressed in bytes per second.
Refer to Section 3.1.2 of <xref target="RFC3471"/> for a table of
commonly used values.
<figure title="Minimum-Bandwidth sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
</section>
<section title="Maximum-Bandwidth sub-TLV" toc="default">
<t>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.</t>
<t>The Type is 6, Length is 4,
and the value comprises of 4-octet bandwidth value encoded in IEEE floating point format (see
<xref target="IEEE.754.1985"/>), expressed in bytes per second.
Refer to Section 3.1.2 of <xref target="RFC3471"/> for a table of
commonly used values.
<figure title="Maximum-Bandwidth sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
</section>
</section>
<section title="Overflow and Underflow Condition" toc="default">
<t>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.</t>
<section title="Overflow-Threshold sub-TLV" toc="default">
<t> The Overflow-Threshold sub-TLV is used to decide if the bandwidth
should be adjusted immediately.
<figure title="Overflow-Threshold sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>The Type is 7, Length is 4, and the value comprises of -
<list style = "symbols">
<t>Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.</t>
<t>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.
</t>
<t>Overflow Threshold: The absolute Overflow-Threshold bandwidth
value, encoded in IEEE floating point format (see
<xref target="IEEE.754.1985"/>), expressed in bytes per second.
Refer to Section 3.1.2 of <xref target="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.</t>
</list></t>
</section>
<section title="Overflow-Threshold-Percentage sub-TLV" toc="default">
<t> The Overflow-Threshold-Percentage sub-TLV is used to decide if the bandwidth
should be adjusted immediately.
<figure title="Overflow-Threshold-Percentage sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>The Type is 8, Length is 4, and the value comprises of -
<list style = "symbols">
<t>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. </t>
<t>Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.</t>
<t>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.
</t>
</list></t>
</section>
<section title="Underflow-Threshold sub-TLV" toc="default">
<t> The Underflow-Threshold sub-TLV is used to decide if the bandwidth
should be adjusted immediately.
<figure title="Underflow-Threshold sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>The Type is 9, Length is 8, and the value comprises of -
<list style = "symbols">
<t>Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.</t>
<t>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.
</t>
<t>Underflow Threshold: The absolute Underflow-Threshold bandwidth
value, encoded in IEEE floating point format (see
<xref target="IEEE.754.1985"/>), expressed in bytes per second.
Refer to Section 3.1.2 of <xref target="RFC3471"/> for a table of
commonly used values. If the decrease
of the current MaxAvgBw from the current bandwidth reservation is
greater than or equal to the threshold value, the underflow
condition is met.
</t>
</list></t>
</section>
<section title="Underflow-Threshold-Percentage sub-TLV" toc="default">
<t> The Underflow-Threshold-Percentage sub-TLV is used to decide if the bandwidth
should be adjusted immediately.
<figure title="Underflow-Threshold-Percentage sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t> The Type is 10, Length is 4, and the value comprises of -
<list style = "symbols">
<t>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.</t>
<t>Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.</t>
<t>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.
</t>
</list></t>
</section>
</section>
</section>
<section title="Real-time Traffic Reporting" toc="default" anchor="sec_real">
<t>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.</t>
<t>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.</t>
<t>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.</t>
<section title="Real-time-Traffic-Report-Interval sub-TLV" toc="default">
<t>The Real-time-Traffic-Report-Interval sub-TLV specifies a time
interval in seconds in which collected bandwidth samples should be
reported to PCE.</t>
<t>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.
<figure title="Real-time-Traffic-Report-Interval sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>There is no default value. This sub-TLV MUST be included to enable
the real-time traffic reporting.</t>
</section>
<section title="Real-time-Traffic-Report-Threshold sub-TLV" toc="default">
<t>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.
<figure title="Real-time-Traffic-Report-Threshold sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure>
</t>
<t>The Type is 12, Length is 4, and the value comprises of -
<list style = "symbols">
<t>Threshold: The absolute threshold bandwidth value, encoded in IEEE
floating point format (see <xref target="IEEE.754.1985"/>), expressed in bytes
per second. Refer to Section 3.1.2 of <xref target="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.
</t>
</list></t>
</section>
<section title="Real-time-Traffic-Report-Threshold-Percentage sub-TLV" toc="default">
<t>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.
<figure title="Real-time-Traffic-Report-Threshold-Percentage sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>The Type is 13, Length is 4, and the value comprises of -
<list style = "symbols">
<t>Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.</t>
<t>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.</t>
</list></t>
</section>
<section title="Real-time-Traffic-Report-Flow-Threshold sub-TLV" toc="default">
<t>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.
<figure title="Real-time-Traffic-Report-Flow-Threshold sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure>
</t>
<t>The Type is 14, Length is 4, and the value comprises of -
<list style = "symbols">
<t>Threshold: The absolute flow threshold bandwidth value, encoded in IEEE
floating point format (see <xref target="IEEE.754.1985"/>), expressed in bytes
per second. Refer to Section 3.1.2 of <xref target="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.</t>
</list></t>
</section>
<section title="Real-time-Traffic-Report-Flow-Threshold-Percentage sub-TLV" toc="default">
<t>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.
<figure title="Real-time-Traffic-Report-Flow-Threshold-Percentage sub-TLV format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>The Type is 15, Length is 4, and the value comprises of -
<list style = "symbols">
<t>Reserved: SHOULD be set to zero on transmission and MUST be
ignored on receipt.</t>
<t>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.</t>
</list></t>
</section>
</section>
</section>
<section title="BANDWIDTH Object" toc="default">
<section title="Auto-Bandwidth Adjusted Bandwidth" toc="default">
<t>As per <xref target="RFC5440"/>, the BANDWIDTH object is
defined with two Object-Type values as following:</t>
<t>
<list style="symbols">
<t>Requested Bandwidth: BANDWIDTH Object-Type is 1.</t>
<t>Re-optimization Bandwidth: Bandwidth of an existing TE LSP
for which a re-optimization is requested. BANDWIDTH Object-Type
is 2.</t>
</list>
</t>
<t>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'.</t>
</section>
<section title="Bandwidth-Usage Report" toc="default" anchor="sec_real_time_bw">
<t>A new BANDWIDTH object type is defined
to report the actual bandwidth usage of a TE LSP.</t>
<t>The Object type is [TBD], the object body has a variable length,
multiples of 4 bytes. The payload format is as follows:
<figure title="Bandwidth-Usage format" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>
</figure> </t>
<t>
<list style="symbols">
<t>BwSample: The actual bandwidth usage, (the BwSample collected at
the end of each sample-interval) encoded in IEEE floating point
format (see <xref target="IEEE.754.1985"/>), expressed in bytes
per second. </t>
</list></t>
<t>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. </t>
<t>The Bandwidth-Usage object can also be used for TE LSPs
without enabling the auto-bandwidth feature, to learn the actual bandwidth
usage of the LSPs for other applications at the stateful PCE.
The details of which are beyond the scope of this document. </t>
</section>
</section>
<section title="The PCRpt Message" toc="default">
<t>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. </t>
<t>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.</t>
<t>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.</t>
<t>The definition of the PCRpt message (see <xref target='I-D.ietf-pce-stateful-pce'/>)
is unchanged by this document.</t>
</section>
<section title="The PCInitiate Message" toc="default">
<t>
For PCE-initiated LSP <xref target='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.</t>
</section>
</section>
<section title="Security Considerations" toc="default">
<t>This document defines a new BANDWIDTH type and AUTO-BANDWIDTH-ATTRIBUTE TLV which do not add any new
security concerns beyond those discussed in <xref target="RFC5440"/>
and <xref target='I-D.ietf-pce-stateful-pce'/> in itself.</t>
<t> 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 <xref target='I-D.ietf-pce-pceps'/>.</t>
</section>
<section title="Manageability Considerations" toc="default">
<section title="Control of Function and Policy" toc="default">
<t>
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.</t>
</section>
<section title="Information and Data Models" toc="default">
<t><xref target="RFC7420"/> describes the PCEP MIB, there are no new MIB Objects
for this document.</t>
</section>
<section title="Liveness Detection and Monitoring" toc="default">
<t>Mechanisms defined in this document do not imply any new liveness detection
and monitoring requirements in addition to those already listed in
<xref target="RFC5440"/>.</t>
</section>
<section title="Verify Correct Operations" toc="default">
<t>Mechanisms defined in this document do not imply any new operation
verification requirements in addition to those already listed in
<xref target="RFC5440"/>.</t>
</section>
<section title="Requirements On Other Protocols" toc="default">
<t>Mechanisms defined in this document do not imply any new requirements
on other protocols.</t>
</section>
<section title="Impact On Network Operations" toc="default">
<t>Mechanisms defined in this document do not have any impact on
network operations in addition to those already listed in
<xref target="RFC5440"/>.</t>
</section>
</section>
<section title="IANA Considerations" toc="default">
<section title="PCEP TLV Type Indicators" toc="default">
<t>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</t>
<t>
<figure title="" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
Value Name Reference
TBD AUTO-BANDWIDTH-ATTRIBUTE [This I.D.]
]]></artwork>
</figure>
</t>
</section>
<section title="AUTO-BANDWIDTH-ATTRIBUTE Sub-TLV" toc="default">
<t>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:
<figure title="" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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
]]></artwork>
</figure> </t>
</section>
<section title="BANDWIDTH Object" toc="default">
<t>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</t>
<t>
<figure title="" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
Object-Class Value Name Reference
5 BANDWIDTH [This I.D.]
Object-Type
TBD: Bandwidth-Usage Report
]]></artwork>
</figure>
</t>
</section>
</section>
<section title="Acknowledgments" toc="default">
<t>We would like to thank Venugopal Reddy, Reeja Paul, Sandeep Boina
and Avantika for their useful comments and suggestions.</t>
</section>
</middle>
<back>
<references title="Normative References">
<?rfc include="reference.RFC.2119.xml" ?>
<?rfc include="reference.RFC.5440.xml" ?>
<?rfc include="reference.I-D.ietf-pce-stateful-pce"?>
<?rfc include="reference.I-D.ietf-pce-pce-initiated-lsp"?>
<!--IEEE.754.1985-->
<reference anchor="IEEE.754.1985">
<front>
<title>Standard for Binary Floating-Point Arithmetic</title>
<author>
<organization>Institute of Electrical and Electronics Engineers</organization>
</author>
<date month="August" year="1985"/>
</front>
<seriesInfo name="IEEE" value="Standard 754"/>
</reference>
</references>
<references title="Informative References">
<?rfc include="reference.RFC.3471.xml" ?>
<?rfc include="reference.RFC.7420.xml" ?>
<?rfc include="reference.I-D.ietf-pce-stateful-pce-app"?>
<?rfc include="reference.I-D.ietf-pce-pceps"?>
</references>
<section title="Contributor Addresses" toc="default">
<t>
<figure title="" suppress-title="false" align="left" alt="" width="" height="">
<artwork xml:space="preserve" name="" type="" align="left" alt="" width="" height=""><![CDATA[
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
]]></artwork>
</figure>
</t>
</section>
</back>
</rfc>| PAFTECH AB 2003-2026 | 2026-04-24 12:24:28 |