One document matched: draft-palle-pce-stateful-pce-initiated-p2mp-lsp-00.xml
<?xml version="1.0" encoding="us-ascii"?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd"[]>
<?rfc toc="yes" ?>
<?rfc tocompact="yes"?>
<?rfc tocdepth="4"?>
<?rfc tocindent="yes"?>
<?rfc symrefs="yes" ?>
<?rfc sortrefs="no"?>
<?rfc rfcedstyle="yes"?>
<?rfc subcompact="no"?>
<?rfc compact="yes" ?>
<?rfc iprnotified="Yes" ?>
<?rfc strict="no" ?>
<rfc ipr="trust200902" category="std" docName="draft-palle-pce-stateful-pce-initiated-p2mp-lsp-00" obsoletes="" updates="" submissionType="IETF" xml:lang="en">
<front>
<title abbrev="PCE-INITIATED-P2MP">PCEP Extensions for PCE-initiated
Point-to-Multipoint LSP Setup in a Stateful PCE Model</title>
<author initials="U" surname="Palle" fullname="Udayasree Palle">
<organization>Huawei Technologies</organization>
<address>
<postal>
<street>Leela Palace</street>
<city>Bangalore</city>
<region>Karnataka</region>
<code>560008</code>
<country>INDIA</country>
</postal>
<email>udayasree.palle@huawei.com</email>
</address>
</author>
<author fullname="Dhruv Dhody" initials="D" surname="Dhody">
<organization abbrev="Huawei Technologies">Huawei Technologies</organization>
<address>
<postal>
<street>Leela Palace</street>
<city>Bangalore</city>
<region>Karnataka</region>
<code>560008</code>
<country>INDIA</country>
</postal>
<email>dhruv.ietf@gmail.com</email>
</address>
</author>
<date month="January" year="2014" />
<area>Routing</area>
<workgroup>PCE Working Group</workgroup>
<abstract>
<t>The Path Computation Element (PCE) has been identified as an
appropriate technology for the determination of the paths of
point-to-multipoint (P2MP) TE LSPs.
The extensions described in
<xref target='I-D.ietf-pce-stateful-pce'></xref> provide
stateful control of Multiprotocol Label Switching (MPLS) Traffic
Engineering Label Switched Paths (TE LSP) via PCE communication
Protocol (PCEP), for a model where the Path Computation Client
(PCC) delegates control over one or more locally configured LSPs to
the PCE. Further <xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>
describes the creation and deletion of PCE-initiated LSPs under the
stateful PCE model. This document provides
extensions required for PCEP so as to enable stateful PCE-Initiated
point-to-multipoint (P2MP) TE LSP instantiation.</t>
</abstract>
</front>
<middle>
<section title="Introduction" toc="default">
<t>As per <xref target="RFC4655"/>, the Path Computation Element
(PCE) is an entity
that is capable of computing a network path or route based on a
network graph, and applying computational constraints. A Path
Computation Client (PCC) may make requests to a PCE for paths to be
computed.</t>
<t><xref target="RFC4857"/> describes how to set up point-to-multipoint
(P2MP) Traffic Engineering Label Switched Paths (TE LSPs) for use in
Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS)
networks. The PCE has been identified as a suitable application for
the computation of paths for P2MP TE LSPs (<xref target="RFC5671"/>).</t>
<t>The PCEP is designed as a communication protocol between PCCs and PCEs
for point-to-point (P2P) path computations and is defined in
<xref target="RFC5440"/>. The extensions of PCEP to request path computation
for P2MP TE LSPs are described in <xref target="RFC6006"/>.</t>
<t>Stateful PCEs are shown to be helpful in many application scenarios,
in both MPLS and GMPLS networks, as illustrated in
<xref target='I-D.ietf-pce-stateful-pce-app'></xref>. These scenarios apply
equally to P2P and P2MP TE LSPs. <xref target='I-D.ietf-pce-stateful-pce'></xref>
provides the fundamental extensions needed for stateful PCE to support
general functionality for P2P TE LSP. Further
<xref target='I-D.palle-pce-stateful-pce-p2mp'></xref> focuses
on the extensions that are necessary in order for the deployment of stateful PCEs
to support P2MP TE LSPs. It includes
mechanisms to effect P2MP LSP state synchronization between PCCs and PCEs,
delegation of control of P2MP LSPs to PCEs, and PCE control of timing and
sequence of P2MP path computations within and across PCEP sessions and
focuses on a model where P2MP LSPs are configured on the PCC and control
over them is delegated to the PCE.</t>
<t><xref target='I-D.ietf-pce-pce-initiated-lsp'></xref> provides the
fundamental extensions needed for stateful PCE-initiated P2P TE LSP
instantiation.</t>
<t>This document describes the setup, maintenance and teardown of PCE-
initiated P2MP LSPs under the stateful PCE model, without the need for
local configuration on the PCC, thus allowing for a dynamic network
that is centrally controlled and deployed.</t>
<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>
<section title="Terminology" toc="default">
<t>Terminology used in this document is same as terminology used in
<xref target='I-D.ietf-pce-stateful-pce'></xref>,
<xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>
and <xref target="RFC6006"/>.</t>
</section>
<section title="Architectural Overview" toc="default" anchor="SEC_M">
<section title="Motivation" toc="default">
<t><xref target='I-D.palle-pce-stateful-pce-p2mp'></xref> provides stateful
control over P2MP TE LSPs that are locally configured on the PCC. This
model relies on the Ingress taking an active role in delegating locally
configured P2MP TE LSPs to the PCE, and is well suited in environments
where the P2MP TE LSP placement is fairly static. However, in environments
where the P2MP TE LSP placement needs to change in response to application
demands, it is useful to support dynamic creation and tear down of P2MP TE LSPs.
The ability for a PCE to trigger the creation of P2MP TE LSPs on demand can
be seamlessly integrated into a controller-based network architecture, where
intelligence in the controller can determine when and where to set up paths.</t>
<t>Section 3 of <xref target='I-D.ietf-pce-pce-initiated-lsp'></xref> further describes
the motivation behind the PCE-Initiated capability, which are equally applicable for
P2MP TE LSPs instantiation.</t>
</section>
<section title="Operation Overview" toc="default">
<t>A PCC or PCE indicates its ability to support PCE provisioned dynamic
LSPs and P2MP operations during the PCEP Initialization Phase via mechanism described
in <xref target="SEC_CA"/>.</t>
<t>As per section 5.1 of
<xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>, the PCE sends a Path Computation
LSP Initiate Request (PCInitiate) message to the PCC to instantiate or delete
a P2P TE LSP. This document extends the PCInitiate message to support
P2MP TE LSP Instantiation (see details in <xref target="SEC_PCINIT"/>).</t>
<t>P2MP TE LSP instantiation and deletion operations are same as P2P LSP Instantiation
as described in section 5.3 and 5.4 of <xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>.
This document focuses on extensions needed for further handling of P2MP TE LSP
Instantiation (see details in <xref target="SEC_INST"/>).</t>
</section>
</section>
<section title="Support of PCE Initiated P2MP TE LSPs" toc="default" anchor="SEC_CA">
<t>As per Section 3.1 of <xref target='RFC6006'></xref>, PCE advertises
P2MP capability via IGP discovery or a P2MP capable TLV in open message.
To support instantiation of PCE-initiated P2MP TE LSPs, this document
extends the advertisement of P2MP capable TLV in open message by all PCEP speakers.
As per Section 4 of <xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>,
PCC or PCE advertises capability for instantiation of PCE-initiated LSPs via
Stateful PCE Capability TLV (LSP-INSTANTIATION-CAPABILITY bit) in open message.
These mechanism when used together indicates the instantiation
capability for P2MP TE LSPs by the PCEP speaker.</t>
</section>
<section title="PCE-initiated P2MP TE LSP Operations" toc="default">
<section title="The PCInitiate message" toc="default" anchor="SEC_PCINIT">
<t>As defined in section 5.1 of <xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>,
PCE sends a PCInitiate message to a PCC to instantiate a P2P TE LSP, this document
extends the format of PCInitiate message for the creation of P2MP TE LSPs but the
creation and deletion operations of P2MP TE LSP are same to the P2P TE LSP.</t>
<t>The format of PCInitiate message is as follows:</t>
<figure align="left" alt="" height="" suppress-title="true"
title="" width="" anchor="SEC_FIG3">
<artwork align="left" alt="" height="" name="" type="" width=""
xml:space="preserve">
<PCInitiate Message> ::= <Common Header>
<PCE-initiated-lsp-list>
Where:
<PCE-initiated-lsp-list> ::= <PCE-initiated-lsp-request>
[<PCE-initiated-lsp-list>]
<PCE-initiated-lsp-request> ::=
(<PCE-initiated-lsp-instantiation>|<PCE-initiated-lsp-deletion>)
<PCE-initiated-lsp-instantiation> ::= <SRP>
<LSP>
<end-point-path-pair-list>
[<attribute-list>]
<PCE-initiated-lsp-deletion> ::= <SRP>
<LSP>
Where:
<end-point-path-pair-list>::=
[<END-POINTS>]
<path>
[<end-point-path-pair-list>]
<path> ::= (<ERO>|<SERO>)
[<path>]
<attribute-list> is defined in [RFC5440] and extended
by PCEP extensions.
</artwork>
</figure>
<t>The PCInitiate message with an LSP object with N bit (P2MP) set is
used to convey operation on a P2MP TE LSP.
The SRP object is used to correlate between initiation requests sent
by the PCE and the error reports and state reports sent by the PCC as described in
<xref target='I-D.ietf-pce-stateful-pce'></xref>. </t>
</section>
<section title="P2MP TE LSP Instantiation" toc="default" anchor="SEC_INST">
<t>The Instantiation operation of P2MP TE LSP is same as defined in section 5.3 of
<xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>. Rules of processing and
error codes remains unchanged. Further, as defined in section 6.1 of
<xref target='I-D.palle-pce-stateful-pce-p2mp'></xref>, N bit MUST be set in LSP object
in PCInitiate message by PCE to specify the instantiation is for P2MP TE LSP and the
PCC or PCE MUST follow the mechanism defined in <xref target='I-D.palle-pce-stateful-pce-p2mp'></xref>
for delegation and updation of P2MP TE LSPs.</t>
</section>
<section title="P2MP TE LSP Deletion" toc="default">
<t>The deletion operation of P2MP TE LSP is same as defined in section 5.4 of
<xref target='I-D.ietf-pce-pce-initiated-lsp'></xref> by sending an LSP Initiate
Message with an LSP object carrying the PLSP-ID of the LSP to be
removed and an SRP object with the R flag set (LSP-REMOVE as per
section 5.2 of <xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>). Rules of processing and
error codes remains unchanged.</t>
</section>
<section title="P2MP TE LSP Delegation and Cleanup" toc="default">
<t>P2MP TE LSP delegation and cleanup operations are same as defined in section 6 of
<xref target='I-D.ietf-pce-pce-initiated-lsp'></xref>. Rules of processing and
error codes remains unchanged.</t>
</section>
</section>
<section title="PCInitiate Message Fragmentation" toc="default">
<t>The total PCEP message length, including the common header, is
16 bytes. In certain scenarios the P2MP LSP Initiate may not
fit into a single PCEP message (initial PCInitiate message).
The F-bit is used in the LSP object to signal that the initial
PCInitiate was too large to fit into a single message and will be
fragmented into multiple messages.</t>
<t>Fragmentation procedure described below for PCInitiate message
is similar to <xref target="RFC6006"/> which describes request and response
message fragmentation.</t>
<section title="PCInitiate Fragmentation Procedure" toc="default">
<t>Once the PCE initiates to set up the P2MP TE LSP,
a PCInitiate message is sent to the PCC. If the
PCInitiate is too large to fit into a single PCInitiate message, the PCE
will split the PCInitiate over multiple messages. Each PCInitiate message
sent by the PCE, except the last one, will have the F-bit set in the
LSP object to signify that the PCInitiate has been fragmented into
multiple messages. In order to identify that a series of PCInitiate messages
represents a single Initiate, each message will use the same PLSP-ID (in this case 0)
and SRP-ID-number.</t>
<t>[Editor Note: P2MP message fragmentation errors associated with a
P2MP path initiation will be defined in future version].</t>
</section>
</section>
<section title="Non-Support of P2MP TE LSP Instantiation for Stateful PCE" toc="default">
<t>The PCEP protocol extensions described in this document for PCC or PCE
with instantiation capability for P2MP TE LSPs MUST NOT be used if PCC or PCE has not
advertised its stateful capability with Instantiation and P2MP capability as per
<xref target="SEC_CA"/>. If this is not the case and Stateful operations on P2MP TE LSPs
are attempted, then a PCErr with error-type 19 (Invalid Operation) and error-value TBD
needs to be generated.</t>
<t>[Editor Note: more information on exact error value is needed]</t>
</section>
<section title="Security Considerations" toc="default">
<t>TBD</t>
</section>
<section title="Manageability Considerations" toc="default">
<section title="Control of Function and Policy" toc="default">
<t>TBD.</t>
</section>
<section title="Information and Data Models" toc="default">
<t>TBD.</t>
</section>
<section title="Liveness Detection and Monitoring" toc="default">
<t>TBD.</t>
</section>
<section title="Verify Correct Operations" toc="default">
<t>TBD.</t>
</section>
<section title="Requirements On Other Protocols" toc="default">
<t>TBD.</t>
</section>
<section title="Impact On Network Operations" toc="default">
<t>TBD.</t>
</section>
</section>
<section title="IANA Considerations" toc="default">
<t>TBD</t>
</section>
<section title="Acknowledgments" toc="default">
<t></t>
</section>
</middle>
<back>
<references title="Normative References">
<?rfc include="reference.RFC.2119.xml" ?>
</references>
<references title="Informative References">
<?rfc include="reference.RFC.4655.xml" ?>
<?rfc include="reference.RFC.4857.xml" ?>
<?rfc include="reference.RFC.5440.xml" ?>
<?rfc include="reference.RFC.5671.xml" ?>
<?rfc include="reference.RFC.6006.xml" ?>
<?rfc include="reference.I-D.ietf-pce-stateful-pce"?>
<?rfc include="reference.I-D.ietf-pce-pce-initiated-lsp"?>
<?rfc include="reference.I-D.palle-pce-stateful-pce-p2mp"?>
<?rfc include="reference.I-D.ietf-pce-stateful-pce-app"?>
</references>
</back>
</rfc>
| PAFTECH AB 2003-2026 | 2026-04-24 12:35:33 |