RSVP-TE Extensions for Multipath Traffic Engineered Directed Acyclic Graph Tunnels
draft-kbr-teas-mptersvp-02
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Kireeti Kompella , Vishnu Pavan Beeram , Chandrasekar R | ||
| Last updated | 2025-10-20 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
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draft-kbr-teas-mptersvp-02
TEAS WG K. Kompella
Internet-Draft V. P. Beeram
Intended status: Standards Track C. Ramachandran
Expires: 23 April 2026 Juniper Networks
20 October 2025
RSVP-TE Extensions for Multipath Traffic Engineered Directed Acyclic
Graph Tunnels
draft-kbr-teas-mptersvp-02
Abstract
A Multipath Traffic Engineered Directed Acyclic Graph (MPTED) tunnel
is a Traffic Engineering (TE) construct that facilitates weighted
load balancing of unicast traffic across a constrained set of paths
optimized for a specific objective.
This document describes the provisioning of an MPTED Tunnel in a TE
network using RSVP-TE.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 23 April 2026.
Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
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extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
1.2. Definition of Terms Used in this Document . . . . . . . . 4
1.2.1. Terms Used Specifically in This Document . . . . . . 4
1.3. Comparison with RSVP Multipath Traffic Engineered Container
Tunnels . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. MPTED Tunnels: Overview of Operation . . . . . . . . . . . . 5
2.1. MPTED Tunnel Originator . . . . . . . . . . . . . . . . . 6
2.1.1. Identification . . . . . . . . . . . . . . . . . . . 6
2.2. Path Computation . . . . . . . . . . . . . . . . . . . . 6
2.2.1. JUNCTION . . . . . . . . . . . . . . . . . . . . . . 7
2.3. MPTED Signaling Source (SS) . . . . . . . . . . . . . . . 7
2.3.1. Versioning . . . . . . . . . . . . . . . . . . . . . 7
2.3.2. Label Allocation . . . . . . . . . . . . . . . . . . 7
2.3.3. JUNCTION State Block (JSB) . . . . . . . . . . . . . 7
2.3.4. Tunnel Status . . . . . . . . . . . . . . . . . . . . 8
2.3.5. In-Place Update vs Make-Before-Break . . . . . . . . 8
3. Signaling for Junction Management . . . . . . . . . . . . . . 8
3.1. Source to Junction (S2J) Messages . . . . . . . . . . . . 9
3.1.1. JunctionCreate . . . . . . . . . . . . . . . . . . . 9
3.1.2. JunctionUpdate . . . . . . . . . . . . . . . . . . . 9
3.1.3. JunctionDelete . . . . . . . . . . . . . . . . . . . 9
3.2. Junction to Source (J2S) Messages . . . . . . . . . . . . 9
3.2.1. JunctionNotify . . . . . . . . . . . . . . . . . . . 9
3.2.2. ResourceNotify . . . . . . . . . . . . . . . . . . . 10
3.3. Junction to Junction (J2J) Messages: . . . . . . . . . . 10
3.3.1. Upstream (J2JU) Messages . . . . . . . . . . . . . . 10
3.3.2. Downstream (J2JD) Messages . . . . . . . . . . . . . 10
4. RSVP Messages and Objects . . . . . . . . . . . . . . . . . . 11
4.1. MPTED Path (M-Path) Message . . . . . . . . . . . . . . . 11
4.2. MPTED Resv (M-Resv) Message . . . . . . . . . . . . . . . 12
4.3. MPTED Pathtear (M-PathTear) Message . . . . . . . . . . . 13
4.4. MPTED Notify (M-Notify) Message . . . . . . . . . . . . . 14
4.5. Resource Notify (RsrcNotify) Message . . . . . . . . . . 15
4.6. Objects . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.6.1. SESSION Object . . . . . . . . . . . . . . . . . . . 16
4.6.2. END POINTS Object . . . . . . . . . . . . . . . . . . 17
4.6.3. JUNCTION Object . . . . . . . . . . . . . . . . . . . 19
4.6.4. JUNCTION PHOPS Object . . . . . . . . . . . . . . . . 20
4.6.5. JUNCTION NHOPS Object . . . . . . . . . . . . . . . . 23
4.6.6. VERSION Object . . . . . . . . . . . . . . . . . . . 28
4.6.7. JUNCTION HOP Object . . . . . . . . . . . . . . . . . 29
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4.6.8. JUNCTION_LABELED_HOP Object . . . . . . . . . . . . . 30
4.6.9. CONDITIONS Object . . . . . . . . . . . . . . . . . . 31
4.6.10. JUNCTION_STATUS . . . . . . . . . . . . . . . . . . . 32
4.6.11. JUNCTION_HOP_STATUS . . . . . . . . . . . . . . . . . 34
4.6.12. RESOURCE_SPEC . . . . . . . . . . . . . . . . . . . . 35
4.6.13. DEG_RESOURCE_SPEC . . . . . . . . . . . . . . . . . . 36
5. Protection . . . . . . . . . . . . . . . . . . . . . . . . . 38
6. Graceful Restart . . . . . . . . . . . . . . . . . . . . . . 39
7. Security Considerations . . . . . . . . . . . . . . . . . . . 39
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 39
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 39
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 39
10.1. Normative References . . . . . . . . . . . . . . . . . . 39
10.2. Informative References . . . . . . . . . . . . . . . . . 39
Appendix A. Signaling Sequences - Examples . . . . . . . . . . . 40
A.1. Initial Setup Sequence . . . . . . . . . . . . . . . . . 40
A.2. Update Sequence - "In-Place" . . . . . . . . . . . . . . 42
A.3. Update Sequence - Add Junction . . . . . . . . . . . . . 44
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 46
1. Introduction
The notions of Multipath Traffic Engineering (MPTE) and of an MPTE
Directed Acyclic Graph (MPTED) tunnel are introduced in
[I-D.draft-kompella-teas-mpte]. An MPTED tunnel is a Traffic
Engineering (TE) construct that contains a constrained set of paths
representing an optimized Directed Acyclic Graph (DAG) from one or
more ingresses to one or more egresses. The paths that make up an
MPTED tunnel traverse a set of junction nodes, and the state
associated with the MPTED at each junction node constitutes a set of
previous-hops and a set of next-hops over which traffic is load
balanced in a weighted fashion. Provisioning an MPTED tunnel in a TE
network using a signaling protocol involves provisioning control and
forwarding plane state at each junction node.
As a signaling protocol, RSVP-TE is widely deployed for provisioning
point-to-point (P2P) TE tunnels [RFC3209] and point-to-multipoint
(P2MP) TE tunnels [RFC4875]. This document discusses the extensions
to RSVP-TE for use as a signaling protocol to provision MPTED
tunnels. MPTED tunnels provisioned using RSVP-TE are referred to as
RSVP MPTED Tunnels.
As discussed in [I-D.draft-kompella-teas-mpte], an MPTED tunnel may
be realized over a Multiprotocol Label Switching (MPLS) forwarding
plane or a native Internet Protocol (IP) v4/v6 forwarding plane using
an appropriate tunnel type. Depending on the deployment needs, a
centralized or a distributed approach MAY be adopted for provisioning
an MPTED tunnel. The focus of this version of the document is on
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discussing how the RSVP-TE protocol is extended to facilitate
distributed provisioning of MPTED Tunnels over an MPLS forwarding
plane in an intra-domain TE network.
1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. These words may also appear in this
document in lower case as plain English words, absent their normative
meanings.
1.2. Definition of Terms Used in this Document
The reader is expected to be familiar with
[I-D.draft-kompella-teas-mpte] where most of the terms used in this
document are defined.
1.2.1. Terms Used Specifically in This Document
P2P: point-to-point; (for a tunnel) unicast tunnel with a single
ingress and a single egress, typically along a single path
1.3. Comparison with RSVP Multipath Traffic Engineered Container
Tunnels
There is a pre-existing (and deployed) attempt to combine TE and
multipath using what we can call an "RSVP Multipath Traffic
Engineered Container (MPTEC) tunnel". An MPTEC contains multiple
dynamically created and individually signaled single-path RSVP P2P
tunnels. These member tunnels are dynamically added and removed from
the container tunnel at the ingress depending on the amount of
traffic steered onto it. Though the container tunnel offers a viable
option for facilitating the load balancing of unicast traffic across
a constrained set of paths individually optimized for a specific
objective, the requirement to individually signal and maintain member
LSP state can be a deterrent in specific scaled deployments.
A key differentiator for an MPTED tunnel over an MPTEC tunnel is that
with the former, traffic is load-balanced across the next hops at
each junction node in the DAG (in a weighted fashion), whereas with
the latter, traffic is load-balanced only at the ingress node (and
typically equally balanced among the next hops). Another
differentiator is that the amount of signaling needed to set up the
tunnel is significantly less for the MPTED tunnel compared to the
MPTEC tunnel. Finally, a MPTEC tunnel has exactly one ingress and
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one egress, whereas an MPTED tunnel can have more than one ingress
and/or egress with relatively little extra state; this feature is
expected to be popular in BGP and multi-homed VPN deployments.
Consider the reference DAG illustrated in Figure 1. An MPTEC tunnel
would need 30 member tunnels to be individually set up to cover all
the paths in this DAG, whereas an MPTED would have a single tunnel.
Focusing on a single node, with MPTEC, R4 would have 30 PSBs and 30
RSBs, whereas with MPTED, R4 would have a single JSB with 2 previous-
hops and 3 next-hops. (The terms PSB, RSB and JSB will be explained
in a later section.)
+---+
--| R9|--
+---+ +---+ / +---+ \
| R2| -----| R5|----- / \
+---+ / +---+ \ / +---+ \
/ \ / \ / ----|R10|---- \
/ \ / \ / / +---+ \ \
/ \/ \/ / \ \
+---+ +---+ +---+ +---+ +---+ +---+
| R1| | R4|------| R6|------| R8|------|R11|------|R14|
+---+ +---+ +---+ +---+ +---+ +---+
\ /\ /\ \ / /
\ / \ / \ \ +---+ / /
\ / \ / \ ----|R12|---- /
+---+ \ +---+ / \ +---+ /
| R3| -----| R7|----- \ /
+---+ +---+ \ +---+ /
--|R13|--
+---+
Figure 1: Reference DAG
2. MPTED Tunnels: Overview of Operation
To instantiate an MPTE tunnel in a network via signaling, three steps
are needed:
1. Provide the configuration of the MPTED (ingresses, egresses,
constraints, etc.) and assign ownership of the DAG to the tunnel
originator (TO).
2. Compute an MPTE DAG that satisfies the constraints. This
function is undertaken by the MPTE Computer (MC).
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3. Signal the required information to the network elements
constituting the DAG to establish the tunnel. This task is
undertaken by the Signaling Source (SS).
These three functions may be performed by one or more entities.
Typical scenarios include:
1. An ingress node of the MPTE DAG does all three functions.
2. An ingress node of the MPTE DAG originates the tunnel, delegates
computation of the DAG to a PCE [RFC5440], receives the result
and signals the tunnel.
3. A PCE originates the tunnel, computes the DAG and delegates
signaling to an ingress node of the DAG.
Other combinations are possible. The subsections that follow
describe each function; the next section describes signaling in
greater detail.
2.1. MPTED Tunnel Originator
The TO for an MPTED tunnel is typically an ingress of the DAG;
however, any node on the DAG can be the TO. In scenarios where the
MPTED tunnel has multiple ingress nodes, one of the ingress nodes may
be designated as the TO. In deployments where a stateful Path
Computation Element (PCE) ([RFC8231], [RFC8281]) model is used to
initiate the setup of RSVP MPTED tunnels, the TO is the PCE.
2.1.1. Identification
The TO is responsible for the identity of an MPTED tunnel. An MPTED
tunnel is uniquely identified by the 2-tuple: <MPTED Originator ID
(MPTED OID), MPTED ID>. The MPTED OID is the IP (v4/v6) (loopback?)
address of the TO. An MPTED ID is an unsigned 32-bit positive
integer unique to each DAG in the namespace of the MPTED originator
(the value 0 is reserved).
2.2. Path Computation
An MPTED may be computed by a path computation engine locally on the
TO or by a PCE. In either case, the Traffic Engineering Database
(TED) used by the path computation engine is augmented with
information indicating whether a topological element supports MPTED
tunnel provisioning via RSVP-TE [I-D.kompella-lsr-mptecap]. The path
computation request for the MPTED carries an MPTED tunnel ID, a set
of ingress nodes, a set of egress nodes, a set of constraints, and an
optimization objective. The path computation result for the MPTED
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contains a set of unordered elements called JUNCTIONs. This set is
communicated to the SS so that the MPTED tunnel can be signaled.
2.2.1. JUNCTION
Each ingress, transit, and egress node on the DAG is a junction and
has a JUNCTION element associated with it. A JUNCTION element
contains the information necessary to provision a specific junction
node in the computed DAG. This version of the document assumes that
all junction nodes in the computed DAG are MPTED RSVP capable. The
information carried in a JUNCTION element includes the bandwidth
coming in and going out of the junction, a list of previous-hops
(JCT-PHOPs), and a list of next-hops (JCT-NHOPs).
2.3. MPTED Signaling Source (SS)
The MPTED SS is responsible for creating, maintaining and ultimately
destroying an MPTE tunnel. It is handed an MPTED tunnel ID and a set
of JUNCTIONs. If signaling is successful, it communicates back to
the TO that the tunnel is ready for traffic.
2.3.1. Versioning
The provisioned state associated with the MPTED tunnel may change
over time, with each instance of the MPTED tunnel getting assigned an
unsigned 32-bit version number (MPTED version). An MPTED tunnel
instance is uniquely identified by the 3-tuple <MPTED OID, MPTED ID,
MPTED version>. The MPTED version is managed by the SS.
2.3.2. Label Allocation
[I-D.draft-kompella-teas-mpte] offers multiple label allocation
schemes for MPTED tunnels realized over an MPLS forwarding plane.
Given the presence of a signaling plane, this document advocates the
use of the "Signaled Label Switching (SigLab)" approach for RSVP
MPTED tunnels.
2.3.3. JUNCTION State Block (JSB)
The control-plane state provisioned on a junction node for a given
MPTED Tunnel is referred to as the JUNCTION State Block (JSB). The
states pertaining to the JCT-PHOPs and JCT-NHOPs contained in the JSB
are referred to as JSB-PHOPs and JSB-NHOPs, respectively.
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2.3.4. Tunnel Status
An MPTED tunnel is deemed "Up" if all the junction nodes are
provisioned as requested. The tunnel is deemed "Up - Degraded" if
some (but not all) paths in the DAG are available for carrying the
end-to-end traffic. The tunnel is deemed "Down" if there are no
paths in the DAG available for carrying the end-to-end traffic.
Based on the difference between the requested bandwidth and the
actual reserved bandwidth on the DAG, local policy on the tunnel
originator will determine if the MPTED Tunnel should be deemed
"Active" (available for traffic to be placed on it) or not.
2.3.5. In-Place Update vs Make-Before-Break
Unless there is a change to the set of constraints used, or an
addition or deletion of topological elements, the shape of the
computed DAG will remain unchanged over the life of an MPTED tunnel.
If the shape of the DAG does not change, the updates to an MPTED
tunnel are localized to the bandwidth allotted to the JUNCTION and
the relative load shares on the JCT-NHOPs. In such a scenario, the
update is carried out in-place and is accompanied by a corresponding
version change.
Suppose the shape of the DAG changes for some inevitable reason,
meaning there is an addition or deletion of JUNCTIONs or an addition
or deletion of JCT-PHOPs/JCT-NHOPs. In that case, the in-place
update to the tunnel may cause temporary traffic disruption. Hence,
there may be a need to adopt a make-before-break approach to updating
the tunnel if the shape of the DAG changes.
3. Signaling for Junction Management
Signaling messages are classified into the following categories:
* (Signaling) Source to Junction node (S2J)
* Junction node to (Signaling) Source (J2S)
* Junction to Junction (J2J)
The underlying RSVP-TE messages used to transmit these messages are
analogous to those used in [RFC3209], but are prefixed with M- to
distinguish them.
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3.1. Source to Junction (S2J) Messages
These are messages signaled from the SS to a junction node on the
DAG. The junction node may be an ingress, a transit, or an egress
node on the DAG.
3.1.1. JunctionCreate
An S2J JunctionCreate message is used to trigger the instantiation of
the "JUNCTION" state on a junction node. Each such message has a
version number encoded within it, which identifies the instance of
the "JUNCTION" being created.
This document leverages the use of RSVP MPTED Path (M-Path) message
to function as an S2J JunctionCreate message.
3.1.2. JunctionUpdate
An S2J JunctionUpdate message is used to trigger the modification of
"JUNCTION" state on a junction node. The version number encoded
within the message identifies the instance of the "JUNCTION" being
modified. The elements of the existing "JUNCTION" entry from the old
instance that are no longer part of the DAG are locally tagged as
candidates for deletion and remain active until explicitly instructed
to do so.
This document leverages the use of RSVP MPTED Path (M-Path) message
to function as an S2J JunctionUpdate message.
3.1.3. JunctionDelete
An S2J JunctionDelete message is used to trigger the deletion of the
JUNCTION state on a junction node. The message MAY include an
instruction to initiate sending a J2J JunctionDelete message to each
associated next hop.
This document leverages the use of RSVP MPTED PathTear (M-PathTear)
message to function as an S2J JunctionDelete message.
3.2. Junction to Source (J2S) Messages
These are messages signaled from a junction node to the SS.
3.2.1. JunctionNotify
A J2S JunctionNotify message is used to notify the SS of the status
of the junction. This message MAY be sent as a response to an S2J
message or be sent unsolicited.
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This document leverages the use of RSVP MPTED Notify (M-Notify)
message to function as a J2S JunctionNotify message.
3.2.2. ResourceNotify
The ResourceNotify message is used to notify the SS of the loss or
degradation of an associated resource (e.g., TE link going down,
maximum bandwidth on the TE link going down).
This document leverages the use of RSVP ResourceNotify message to
function as a J2S ResourceNotify message.
3.3. Junction to Junction (J2J) Messages:
These are messages exchanged between immediately adjacent junction
nodes.
3.3.1. Upstream (J2JU) Messages
3.3.1.1. JunctionNextHopReservation
The J2JU JunctionNextHopReserve message is sent to an immediate
upstream junction node and is used to facilitate (a) ordered
programming of labeled routes at each junction node on the DAG, (b)
ordered admission control and bandwidth reservation on traversed TE
links, and (c) ordered addition of next hops when changing the shape
of the DAG.
This document leverages the use of RSVP MPTED Resv (M-Resv) message
to function as a J2JU JunctionNextHopReservation message.
3.3.1.2. JunctionDown
The J2JU JunctionDown message is used to notify an immediate upstream
junction node of the local junction state going "Down".
This document leverages the use of RSVP M-Notify message to function
as a J2JU JunctionDown message.
3.3.2. Downstream (J2JD) Messages
3.3.2.1. JunctionDelete
The J2JD JunctionDelete message is sent to a JUNCTION next-hop to
delete the state, with the condition that the deletion will be
propagated further downstream only for next-hops already marked for
deletion.
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This document leverages the use of RSVP M-PathTear message to
function as a J2JD JunctionDelete message.
4. RSVP Messages and Objects
4.1. MPTED Path (M-Path) Message
An M-Path message is an S2J message that is used for creating or
updating control and forwarding plane state associated with an MPTED
tunnel on a specific junction node. The M-Path message includes the
following information:
* MPTED tunnel identifier (SESSION Object)
* MPTED tunnel instance identifier (VERSION Object)
* MPTED tunnel name (SESSION_ATTRIBUTE Object)
* Setup/Hold Priority (SESSION_ATTRIBUTE Object)
* Label type (LABEL_REQUEST Object)
* Junction information - identifier, bandwidth, phops, and nhops
with their relative load-shares (<junction-descriptor>)
When a non-egress junction node receives an M-Path message for a new
JUNCTION state, it constructs a JSB with the associated JSB-NHOPs and
JSB-PHOPs using the information encoded in the message. If the non-
egress junction node receives an M-Path for an existing JUNCTION
state with a version change, it updates the corresponding JSB using
the information encoded in the message. The JSB update may involve
adding new JSB-NHOPs and JSB-PHOPs and marking JSB-NHOPs and JSB-
PHOPs that are no longer part of the JUNCTION state as candidates for
deletion. After the JSB is constructed or updated, the non-egress
junction node waits for an M-Resv message to be received from each
available JCT-NHOP.
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When an egress junction node receives an M-Path message for a new
JUNCTION state, it constructs a JSB, assigns a label for each JCT-
PHOP, and programs the forwarding plane state, thus completing the
JUNCTION provisioning at the egress. If the egress junction node
receives an M-Path message for an existing JUNCTION state, it updates
the corresponding JSB using the information encoded in the message.
The JSB update may involve adding new JSB-PHOPs, and marking JSB-
PHOPs that are no longer part of the JUNCTION state as candidates for
deletion. After the JSB is constructed/updated, the egress junction
node sends an MPTED Resv (M-Resv) message to each JCT-PHOP, and an
MPTED Notify (M-Notify) message directly to the tunnel signaling
source.
<M-Path Message> ::= <Common Header> [<INTEGRITY>]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ]
<SESSION> [<END_POINTS>]
<TIME_VALUES> <VERSION>
<LABEL_REQUEST> <SESSION_ATTRIBUTE>
<junction-descriptor>
<junction-descriptor> ::= <JUNCTION> <junction-elements>
<junction-elements> ::= ( <JUNCTION_PHOPS> | <JUNCTION_NHOPS> |
( <JUNCTION_PHOPS> <JUNCTION_NHOPS> ))
4.2. MPTED Resv (M-Resv) Message
An M-Resv message is a J2J message that is used to signal the label
that an upstream junction node needs to program for a specific next
hop. The M-Resv message includes the following information:
* MPTED tunnel identifier (SESSION Object)
* MPTED tunnel instance identifier (VERSION Object)
* Hop specific information - Hop identifier, Label, and MTU (a list
of JUNCTION_LABELED_HOP Objects)
When a transit junction node receives an M-Resv message from all
available JCT-NHOPs, it performs admission control, assigns a label
to each JCT-PHOP, programs the forwarding plane state, and sends an
M-Resv message to each JCT-PHOP and an M-Notify message directly to
the tunnel signaling source. No message is sent out until M-Resv
messages from all available JCT-NHOPs have been received and
processed.
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When an ingress junction node receives an M-Resv message from all
available JCT-NHOPs, it performs admission control, programs the
forwarding plane state, and notifies the tunnel signaling source.
<M-Resv Message> ::= <Common Header> [ <INTEGRITY> ]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ]
<SESSION>
<TIME_VALUES> <VERSION>
<junction-labeled-hops-list>
<junction-labeled-hops-list> ::= <JUNCTION_LABELED_HOP>
[ <junction-labeled-hops-list> ]
4.3. MPTED Pathtear (M-PathTear) Message
An M-PathTear message may be used as either an S2J message or a J2J
message. When an S2J M-PathTear is used for deleting the state on a
junction node, the message includes the following information:
* MPTED tunnel identifier (SESSION Object)
* MPTED tunnel instance identifier (VERSION Object)
* Optionally, an instruction to propagate the deletion request
downstream (CONDITIONS Object)
When a junction node receives an S2J M-PathTear message, it deletes
the matching JSB. It sends an M-Notify message to the tunnel
signaling source, indicating that the junction deletion is complete.
If the M-PathTear carries an optional instruction to propagate the
deletion further downstream, the junction node sends a J2J M-PathTear
to each associated JCT-NHOP before deleting the JSB.
When a J2J M-Pathtear is used for deleting a specific hop state on a
downstream junction node, the message includes the following
information:
* MPTED tunnel identifier (SESSION Object)
* MPTED tunnel instance identifier (VERSION Object)
* Hop identifier (JUNCTION_HOP Object)
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During the make-before-break update of an MPTED tunnel, when a
junction node completes updating all JCT-PHOPs matching the new
version, and determines that there are no JCT-PHOPs pending deletion,
it checks if there are any JCT-NHOPs marked for deletion. If such
JCT-NHOPs exist, the junction node sends a J2J M-PathTear for each of
those JCT-NHOPs with the old version.
When a junction node receives a J2J M-PathTear, it cleans up the
corresponding JCT-PHOP state. If there are no other JCT-PHOPs, then
it cleans up the JSB and propagates the J2J M-PathTear to each
associated JCT-NHOP. If there are other JCT-PHOPs present, but none
of them are pending deletion, then it propagates the J2J M-PathTear
only to those JCT-NHOPs that have already been marked for deletion.
<M-PathTear Message> ::= <Common Header> [ <INTEGRITY> ]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ]
<SESSION> <VERSION>
[ <JUNCTION_HOP> ] | [ <CONDITIONS> ]
4.4. MPTED Notify (M-Notify) Message
An M-Notify message may be used as either a J2S message or a J2J
message. A junction node sends a J2S M-Notify message to the tunnel
signaling source to indicate the status of the junction. A junction
node may send a J2S M-Notify message in response to an S2J message or
unsolicited. A J2S M-Notify message includes the following
information:
* MPTED tunnel identifier (SESSION Object)
* MPTED tunnel instance identifier (VERSION Object)
* MTU (JUNCTION_STATUS Object)
* Status (JUNCTION_STATUS Object)
If the Status is not "Degraded", the M-Notify message includes the
following additional information:
* Reserved bandwidth on the junction (JUNCTION_STATUS Object)
* List of JCT-PHOPs that are "Down"
* List of JCT-NHOPs that are "Down/Degraded" and the reserved
bandwidth on each corresponding TE link.
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A junction node sends a J2J M-Notify message to the upstream junction
node to indicate that it is "Down" . A J2J M-Notify message includes
the following information:
* MPTED tunnel identifier (SESSION Object)
* MPTED tunnel instance identifier (VERSION Object)
* Hop Identifier (JUNCTION_HOP_STATUS Object)
* Status (JUNCTION_HOP_STATUS Object)
When an upstream junction node receives a J2J M-Notify indicating
that the junction on the specified JCT-NHOP is "Down", it sets the
load-share on the JCT-NHOP to "zero" and reprograms the labeled
routes.
<M-Notify Message> ::= <Common Header> [<INTEGRITY>]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ]
<SESSION> <VERSION>
(<JUNCTION_HOP_STATUS> |
<junction status descriptor>)
<junction status descriptor> ::= <JUNCTION_STATUS>
[ <degraded junction-elements> ]
<degraded junction-elements> ::= ( <JUNCTION_PHOPS> |
<JUNCTION_NHOPS> |
( <JUNCTION_PHOPS>
<JUNCTION_NHOPS> ))
4.5. Resource Notify (RsrcNotify) Message
A RsrcNotify is a J2S message that is used to notify the tunnel
signaling source of link unavailability or degradation. A RsrcNotify
message includes the following information:
* A list of unavailable resources (list of RESOURCE_SPEC objects)
* A list of degraded resources (list of DEG_RESOURCE_SPEC objects).
When a TE link goes down, the junction node sends a RsrcNotify to
notify each impacted tunnel signaling source that the specified TE
link is no longer available.
When the maximum reservable bandwidth of a TE link is reduced (for
example, a member link on an Aggregate Ethernet link fails), the
junction node selects a set of impacted tunnel signaling sources and
notifies them that the specified TE link has diminished capacity. In
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this scenario, the information carried in the RsrcNotify message is
customized for the recipient. It includes the amount of per-priority
bandwidth usage that the tunnel signaling source would need to reduce
on that TE link.
<ResourceNotify Message> ::= <Common Header> [<INTEGRITY>]
[ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
[ <MESSAGE_ID> ]
( <unavailable-resources> |
<degraded-resources> |
( <unavailable-resources>
<degraded-resources> ))
<unavailable resources> ::=
(( <RESOURCE_SPEC> <unavailable resources> ) |
<RESOURCE_SPEC> )
<degraded resources> ::=
(( <DEG_RESOURCE_SPEC> <degraded resources> ) |
<DEG_RESOURCE_SPEC> )
4.6. Objects
4.6.1. SESSION Object
4.6.1.1. MPTED IPv4 Session
Class = SESSION, MPTED_IPv4 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPTED ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPTED Originator ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* MPTED ID:
- A 32 bit identifier that remains constant over the life of the
MPTED tunnel.
* MPTED Originator ID:
- IPv4 address of the originator of the MPTED tunnel.
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4.6.1.2. MPTED IPv6 Session
Class = SESSION, MPTED_IPv6 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPTED ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MPTED Originator ID (16 bytes) |
| |
| ....... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* MPTED ID:
- A 32 bit identifier that remains constant over the life of the
MPTED tunnel.
* MPTED Originator ID:
- IPv6 address of the originator of the MPTED tunnel.
4.6.2. END POINTS Object
Class = END_POINTS (TBD), C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// (TLVs) //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* TLVs
- The contents of an END_POINTS object are a series of TLVs.
If an M-Path message contains multiple END_POINTS objects, only the
first object is meaningful. Subsequent END_POINTS objects MAY be
ignored and SHOULD NOT be propagated.
4.6.2.1. IPv4_Endpoints TLV
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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 | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| End-point Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x01 Series of IPv4 Endpoints.
* Length:
- Total length of the TLV. It varies based on the number of
addresses encoded.
* Flags:
- 0x01 Ingress (I): Presence of this flag denotes all specified
addresses in the TLV as ingresses and its absence denotes all
addresses in the TLV as egresses.
* End-point Address
- Ipv4 address of the endpoint.
4.6.2.2. IPv6_Endpoints TLV
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 | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| End-point Address (16 bytes) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x02 Series of IPv6 Endpoints.
* Length:
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- Total length of the TLV. It varies based on the number of
addresses encoded.
* Flags:
- 0x01 Ingress (I): Presence of this flag denotes all specified
addresses in the TLV as ingresses and its absence denotes all
addresses in the TLV as egresses.
* End-point Address
- Ipv6 address of the endpoint.
4.6.3. JUNCTION Object
4.6.3.1. JUNCTION_IPv4
Class = JUNCTION, JUNCTION_IPv4 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Junction ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Junction ID:
- IPv4 address of the junction node.
* Version:
- Instance identifier of the JUNCTION state.
* Bandwidth:
- Bandwidth coming into the junction node (encoded as a 32-bit
IEEE floating point number). The units are bytes per second.
4.6.3.2. JUNCTION_IPv6
Class = JUNCTION, JUNCTION_IPv6 C-Type = TBD
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Junction ID (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Junction ID:
- IPv6 address of the junction node.
* Bandwidth:
- Bandwidth coming into the junction node (encoded as a 32-bit
IEEE floating point number). The units are bytes per second.
4.6.4. JUNCTION PHOPS Object
Class = JUNCTION_PHOPS (TBD), C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// (TLVs) //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* TLVs:
- The contents of a JUNCTION_PHOPS object are a series of TLVs.
4.6.4.1. JUNCTION_PHOP_IPv4 TLV
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 | Length | Rsvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Peer Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* Type:
- 0x01 Series of IPv4 PHOPs
* Length:
- Total length of the TLV. It varies based on the number of IPv4
PHOPs encoded.
* IPv4 Peer Address:
- IPv4 address of the previous hop (remote end of the TE link)
* Peer Interface Index:
- Index of the peer interface (remote end of the TE link)
4.6.4.2. JUNCTION_PHOP_IPv4_Label TLV
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 | Length | Rsvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Peer Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x02 Series of IPv4 PHOPs with respective assigned labels.
* Length:
- Total length of the TLV. It varies based on the number of
entities encoded.
* IPv4 Peer Address:
- IPv4 address of the previous hop (remote end of the TE link).
* Peer Interface Index:
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- Index of the peer interface (remote end of the TE link).
* Label:
- Assigned label for the PHOP.
4.6.4.3. JUNCTION_PHOP_IPv6 TLV
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 | Length | Rsvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Peer Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x03 Series of IPv6 PHOPs
* Length:
- Total length of the TLV. It varies based on the number of IPv6
PHOPs encoded.
* IPv6 Peer Address:
- IPv6 address of the previous hop (remote end of the TE link).
* Peer Interface Index:
- Index of the peer interface (remote end of the TE link).
4.6.4.4. JUNCTION_PHOP_IPv6_Label TLV
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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 | Length | Rsvd |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Peer Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x04 Series of IPv6 PHOPs with respective assigned labels.
* Length:
- Total length of the TLV. It varies based on the number of
entities encoded.
* IPv6 Peer Address:
- IPv6 address of the previous hop (remote end of the TE link).
* Peer Interface Index:
- Index of the peer interface (remote end of the TE link).
* Label:
- Assigned label for the PHOP.
4.6.5. JUNCTION NHOPS Object
Class = JUNCTION_NHOPS (TBD), C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// (TLVs) //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* TLVs:
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- The contents of a JUNCTION_NHOPS object are a series of TLVs.
4.6.5.1. JUNCTION_NHOP_IPv4 TLV
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 | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ipv4 Peer Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Load-Share | Res |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x01 Series of IPv4 NHOPs
* Length:
- Total length of the TLV. It varies based on the number of IPv4
NHOPs encoded.
* Flags:
- 0x01 Backup (B): Presence of this flag denotes the specified
next-hop as a backup next-hop.
* IPv4 Peer Address:
- IPv4 address of the previous hop (remote end of the TE link).
* Peer Interface Index:
- Index of the peer interface (remote end of the TE link).
* Load-Share:
- Relative share of the outgoing bandwidth.
4.6.5.2. JUNCTION_NHOP_IPv4_STATUS TLV
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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 | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ipv4 Peer Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Load-Share | MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x02 Series of IPv4 NHOP Statuses
* Length:
- Total length of the TLV. It varies based on the number of IPv4
NHOP statuses encoded.
* Flags:
- 0x01 Backup (B): Presence of this flag denotes the specified
next-hop as a backup next-hop.
* IPv4 Peer Address:
- IPv4 address of the previous hop (remote end of the TE link).
* Peer Interface Index:
- Index of the peer interface (remote end of the TE link).
* Load-Share:
- Relative share of the outgoing bandwidth.
* MTU:
- MTU value received from the next-hop
* Reserved Bandwidth:
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- Bandwidth reserved on the TE link associated with the next-hop
(encoded as a 32-bit IEEE floating point number). The units
are bytes per second.
4.6.5.3. JUNCTION_NHOP_IPv6 TLV
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 | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ipv6 Peer Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Load-Share | Res |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x03 Series of IPv6 NHOPs
* Length:
- Total length of the TLV. It varies based on the number of IPv6
NHOPs encoded.
* Flags:
- 0x01 Backup (B): Presence of this flag denotes the specified
next-hop as a backup next-hop.
* IPv6 Peer Address:
- IPv6 address of the previous hop (remote end of the TE link).
* Peer Interface Index:
- Index of the peer interface (remote end of the TE link).
* Load-Share:
- Relative share of the outgoing bandwidth.
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4.6.5.4. JUNCTION_NHOP_IPv6_STATUS TLV
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 | Length | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Ipv6 Peer Address (16 bytes |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Load-Share | MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Type:
- 0x04 Series of IPv6 NHOP Statuses
* Length:
- Total length of the TLV. It varies based on the number of IPv6
NHOP statuses encoded.
* Flags:
- 0x01 Backup (B): Presence of this flag denotes the specified
next-hop as a backup next-hop.
* IPv6 Peer Address:
- IPv6 address of the previous hop (remote end of the TE link).
* Peer Interface Index:
- Index of the peer interface (remote end of the TE link).
* Load-Share:
- Relative share of the outgoing bandwidth.
* MTU:
- MTU value received from the next-hop
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* Reserved Bandwidth
- Bandwidth reserved on the TE link associated with the next-hop
(encoded as a 32-bit IEEE floating point number). The units
are bytes per second.
4.6.6. VERSION Object
Class = VERSION, Version C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Class = VERSION, Version_SS_v4 C-Type = TBD
* Version ID:
- Instance identifier of the MPTED tunnel.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Signaling Source ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Version ID:
- Instance identifier of the MPTED tunnel.
* Signaling Source ID:
- IPv4 address of the MPTED tunnel signaling source.
This C-Type is used only if the MPTED tunnel originator is different
from the signaling source.
Class = VERSION, Version_SS_v6 C-Type = TBD
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Signaling Source ID (16 bytes) |
| |
| ....... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Version ID:
- Instance identifier of the MPTED tunnel.
* Signaling Source ID:
- IPv6 address of the MPTED tunnel signaling source.
This C-Type is used only if the MPTED tunnel originator is different
from the signaling source.
4.6.7. JUNCTION HOP Object
Class = JUNCTION_HOP, JUNCTION_HOP_v4 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Hop Address:
- IPv4 address of the hop of interest.
* Hop Interface Index:
- Interface index of the hop of interest.
Class = JUNCTION_HOP, JUNCTION_HOP_v6 C-Type = TBD
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Hop Address:
- IPv6 address of the hop of interest.
* Hop Interface Index:
- Interface index of the hop of interest.
4.6.8. JUNCTION_LABELED_HOP Object
Class = JUNCTION_LABELED_HOP, JUNCTION_LABELED_HOP_IPv4_Label C-Type
= TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | Res |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Hop Address:
- IPv4 address of the hop of interest.
* Hop Interface Index:
- Interface index of the hop of interest.
* MTU:
- MTU value associated with the specified hop.
* Label:
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- Label associated with the specified hop.
Class = JUNCTION_LABELED_HOP, JUNCTION_LABELED_HOP_IPv6 TLV C-Type =
TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Interface Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | Res |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Hop Address:
- IPv6 address of the hop of interest.
* Hop Interface Index:
- Interface index of the hop of interest.
* MTU:
- MTU value associated with the specified hop.
* Label:
- Label associated with the specified hop.
4.6.9. CONDITIONS Object
Class = CONDITIONS, C-Type = 1
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags (Reserved) |J|M|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Flags:
- J-Bit: Propagate the deletion request downstream.
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4.6.10. JUNCTION_STATUS
Class = JUNCTION_STATUS, JUNCTION_STATUS_Ipv4 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Junction ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Junction ID:
- IPv4 address of the junction node.
* MTU:
- MTU of the junction node.
* Flags:
- U-Bit: UP Status.
- D-Bit: Down Status.
- G-Bit: Degraded Status.
Class = JUNCTION_STATUS, JUNCTION_STATUS_Ipv6 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Junction ID (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Junction ID:
- IPv6 address of the junction node.
* MTU:
- MTU of the junction node.
* Flags:
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- U-Bit: UP Status.
- D-Bit: Down Status.
- G-Bit: Degraded Status.
Class = JUNCTION_STATUS, JUNCTION_STATUS_Degraded_Ipv4 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Junction ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Junction ID:
- IPv4 address of the junction node.
* MTU:
- MTU of the junction node.
* Flags:
- U-Bit: UP Status.
- D-Bit: Down Status.
- G-Bit: Degraded Status.
* Reserved Bandwidth:
- Bandwidth reserved for the junction (encoded as a 32-bit IEEE
floating point number).
Class = JUNCTION_STATUS, JUNCTION_STATUS_Degraded_Ipv6 C-Type = TBD
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Junction ID (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Junction ID:
- IPv6 address of the junction node.
* MTU:
- MTU of the junction node.
* Flags:
- U-Bit: UP Status.
- D-Bit: Down Status.
- G-Bit: Degraded Status.
* Reserved Bandwidth:
- Bandwidth reserved for the junction (encoded as a 32-bit IEEE
floating point number).
4.6.11. JUNCTION_HOP_STATUS
Class = JUNCTION_HOP_STATUS, JUNCTION_HOP_IPv4_STATUS C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Res | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Hop Address:
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- IPv4 address of the hop of interest.
* Hop Index:
- Interface index of the hop of interest.
* Flags:
- U-Bit: UP Status.
- D-Bit: Down Status.
- G-Bit: Degraded Status.
Class = JUNCTION_HOP_STATUS, JUNCTION_HOP_IPv6_STATUS C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Res | Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Hop Address:
- IPv6 address of the hop of interest.
* Hop Index:
- Interface index of the hop of interest.
* Flags:
- U-Bit: UP Status.
- D-Bit: Down Status.
- G-Bit: Degraded Status.
4.6.12. RESOURCE_SPEC
Class = RESOURCE_SPEC, RESOURCE_SPEC_Ipv4 C-Type = TBD
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Link Address:
- IPv4 address of the unavailable TE link.
* Link Index:
- Index of the unavailable TE link.
Class = RESOURCE_SPEC, RESOURCE_SPEC_Ipv6 C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Link Address:
- IPv6 address of the unavailable TE link.
* Link Index:
- Index of the unavailable TE link.
4.6.13. DEG_RESOURCE_SPEC
Class = DEG_RESOURCE_SPEC, DEG_RESOURCE_SPEC_Ipv4 C-Type = TBD
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max Reservable Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 0 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 1 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 2 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 3 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 4 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 5 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 6 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 7 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Link Address:
- IPv4 address of the degraded TE link.
* Link Index:
- Index of the degraded TE link.
* Max Reservable Bandwidth:
- Maximum reservable bandwidth on the degraded TE link
* Prio x Degraded Bandwidth:
- Amount of bandwidth to be reduced for priority x.
Class = DEG_RESOURCE_SPEC, DEG_RESOURCE_SPEC_Ipv6 C-Type = TBD
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Address (16 bytes) |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Index |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max Reservable Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 0 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 1 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 2 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 3 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 4 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 5 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 6 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prio 7 Degraded Bandwidth (32-bit IEEE floating point number) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Link Address:
- IPv6 address of the degraded TE link.
* Link Index:
- Index of the degraded TE link.
* Max Reservable Bandwidth:
- Maximum reservable bandwidth on the degraded TE link
* Prio x Degraded Bandwidth:
- Amount of bandwidth to be reduced for priority x.
5. Protection
(To be added in a later revision.)
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6. Graceful Restart
(To be added in a later revision.)
7. Security Considerations
(To be added in a later revision.)
8. IANA Considerations
(To be added in a later revision.)
9. Acknowledgments
The authors would like to thank Sudharsana Venkatraman for her input
from discussions.
10. References
10.1. Normative References
[I-D.draft-kompella-teas-mpte]
Kompella, K., Jalil, L., Khaddam, M., and A. Smith,
"Multipath Traffic Engineering", Work in Progress,
Internet-Draft, draft-kompella-teas-mpte-01, 7 July 2025,
<https://datatracker.ietf.org/doc/html/draft-kompella-
teas-mpte-01>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<https://www.rfc-editor.org/rfc/rfc3209>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.
10.2. Informative References
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[I-D.kompella-lsr-mptecap]
Kompella, K., "Multipath Traffic Engineering
Capabilities", Work in Progress, Internet-Draft, draft-
kompella-lsr-mptecap-00, 7 July 2025,
<https://datatracker.ietf.org/doc/html/draft-kompella-lsr-
mptecap-00>.
[RFC4875] Aggarwal, R., Ed., Papadimitriou, D., Ed., and S.
Yasukawa, Ed., "Extensions to Resource Reservation
Protocol - Traffic Engineering (RSVP-TE) for Point-to-
Multipoint TE Label Switched Paths (LSPs)", RFC 4875,
DOI 10.17487/RFC4875, May 2007,
<https://www.rfc-editor.org/rfc/rfc4875>.
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol (PCEP)", RFC 5440,
DOI 10.17487/RFC5440, March 2009,
<https://www.rfc-editor.org/rfc/rfc5440>.
[RFC8231] Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for Stateful PCE", RFC 8231,
DOI 10.17487/RFC8231, September 2017,
<https://www.rfc-editor.org/rfc/rfc8231>.
[RFC8281] Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for PCE-Initiated LSP Setup in a Stateful PCE
Model", RFC 8281, DOI 10.17487/RFC8281, December 2017,
<https://www.rfc-editor.org/rfc/rfc8281>.
Appendix A. Signaling Sequences - Examples
A.1. Initial Setup Sequence
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MPTED Tunnel R1toR8
Originator, Computer, Signaling Source: R1
.----------------.
3G | | 2.5G
+---+ +---+
| R2| -----| R5|-----
+---+ / +---+ \
/ \ / \
/ \ / \
6G / \/ 3G 1G \ 6G
+---+ +---+ +---+ +---+
| R1| | R4|------| R6|------| R8|
+---+ +---+ +---+ +---+
\ /\ /
\ / \ /
\ / \ /
+---+ \ +---+ /
| R3| -----| R7|-----
+---+ +---+
3G | | 2.5G
.----------------.
Link Metrics:
R2-R4, R4-R5, R3-R4, R4-R7: 10
R4-R6, R6-R8: 15
Rest of the links: 20
Figure 2: MPTED Tunnel Setup
* Initiation of setup sequence on MPTED tunnel signaling source, R1:
- R1 sends an M-Path message to each junction node (R2, R3, R4,
R5, R6, R7, and R8)
- R1 processes the ingress JUNCTION, constructs a JSB, and waits
for an M-Resv message to arrive from each JCT-NHOP (R2 and R3).
* M-Path message processing on transit junction nodes (R2, R3, R4,
R5, R6, R7):
- Each transit junction node processes the JUNCTION, constructs a
JSB, and waits for an M-Resv message to arrive from each JCT-
NHOP.
* M-Path message processing on egress junction node, R8.
- R8 processes the JUNCTION and constructs a JSB.
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- R8 sends an M-Resv message to each JCT-PHOP (R5, R6, and R7)
with IMPLICIT NULL Label (3). -R8 sends an M-Notify message to
R1, indicating that the junction processing is complete at R8.
* M-Resv message processing on transit junction nodes (R2, R3, R4,
R5, R6, R7):
- Each transit junction node waits until M-Resv messages are
received from all available JCT-NHOPs and then:
o Allocates a label for each JCT-PHOP and programs the
corresponding labeled route.
o Sends an M-Resv message to each JCT-PHOP with the
corresponding allocated label.
o Sends an M-Notify message to R1, indicating that the
junction processing is complete on the node.
* M-Resv message processing on ingress junction node, R1:
- R1 waist until M-Resv messages are received from all JCT-NHOPs
(R2 and R3) and then:
- Programs a route for the MPTED tunnel.
- Notifies the signaling source (itself) that the junction
processing is complete on the ingress node.
* M-Notify message processing on the signaling source:
- The signaling source (R1) considers the setup sequence complete
when confirmation of junction provisioning is received from all
junctions.
o If all the junctions indicate that the JUNCTION is "Up",
then the status of the MPTED Tunnel is deemed "Up".
o If all the junctions indicate that the JUNCTION is "Down",
then the status of the MPTED Tunnel is deemed "Down".
o In all other scenarios, the status of the MPTED Tunnel is
deemed to be "Degraded".
A.2. Update Sequence - "In-Place"
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MPTED Tunnel R1toR8
Originator, Computer, Signaling Source: R1
.----------------.
3G->6 | | 2.5G->4.5G
+---+ +---+
| R2| -----| R5|-----
+---+ / +---+ \
/ \ / \
/ \ / \
6G->9 / \/3G->4.5G 1G->1.5G \ 6G->9G
+---+ +---+ +---+ +---+
| R1| | R4|------| R6|------| R8|
+---+ +---+ +---+ +---+
\ /\ /
\ / \ /
\ / \ /
+---+ \ +---+ /
| R3| -----| R7|-----
+---+ +---+
3G | | 2.5G->3G
.----------------.
Link Metrics:
R2-R4, R4-R5, R3-R4, R4-R7: 10
R4-R6, R6-R8: 15
Rest of the links: 20
Figure 3: MPTED Tunnel Update - In-Place
* Initiation of update sequence on MPTED signaling source, R1:
- R1 sends an M-Path message with a new version to each junction
node (R2, R3, R4, R5, R6, R7, and R8)
- R1 processes the updated ingress JUNCTION, updates the JSB, and
waits for an M-Resv message to arrive from each JCT-NHOP (R2
and R3).
* M-Path message processing on transit junction nodes (R2, R3, R4,
R5, R6, R7):
- Each transit junction node processes the JUNCTION, updates the
JSB, and waits for an M-Resv message with the new version to
arrive from each JCT-NHOP.
* M-Path message processing on egress junction node, R8:
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- R8 processes the JUNCTION and updates the JSB.
- R8 sends an M-Resv message with the new version to each JCT-
PHOP (R5, R6, and R7)
- R8 sends an M-Notify message to R1, indicating that the
junction update processing is complete at R8.
* M-Resv message processing on transit junction nodes (R2, R3, R4,
R5, R6, R7):
- Each transit junction node waits until M-Resv messages with the
new version are received from all available JCT-NHOPs and then:
o Reprograms the next-hops on the corresponding labeled route
with updated load share (if needed).
o Sends an M-Resv message with the new version to each JCT-
PHOP.
o Sends an M-Notify message to R1, indicating that the
junction update processing is complete on the node.
* M-Resv message processing on ingress junction node, R1:
- R1 waist until M-Resv messages with the new version are
received from all JCT-NHOPs (R2 and R3) and then:
o Reprograms the next-hops on the route for the MPTED tunnel
with updated load share (if needed)
o Notifies the signaling source (itself) that the junction
update processing is complete on the ingress node.
* M-Notify message processing on the signaling source:
- The signaling source (R1) considers the "in-place" update
sequence complete when confirmation of junction update is
received from all junctions.
A.3. Update Sequence - Add Junction
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+---+
2G|Add|
.-------| R9|--------.
| +---+ |
| |
| .----------------. |
| | | | 6G->5.67G
+---+ +---+
6G | R2| -----| R5|-----
+---+ / +---+ \
/ \ / \
/ \ / \
12G / \/6G->5G 2G->1.67G \ 12G
+---+ +---+ +---+ +---+
| R1| | R4|------| R6|------| R8|
+---+ +---+ +---+ +---+
\ /\ /
\ / \ /
\ / \ /
+---+ \ +---+ /
| R3| -----| R7|-----
+---+ +---+
6G | | 5G->4.67G
.----------------.
Link Metrics:
R2-R4, R4-R5, R3-R4, R4-R7: 10
R4-R6, R6-R8: 15
Rest of the links: 20
Junction R9 is added to the DAG
Figure 4: MPTED Tunnel Update - Add Junction
* Initiation of update sequence on MPTED signaling source, R1:
- R1 sends an M-Path message with a new version to each junction
node (R2, R3, R4, R5, R6, R7, R8, and the newly added R9)
- R1 processes the updated ingress JUNCTION, updates the JSB, and
waits for an M-Resv message to arrive from each JCT-NHOP (R2
and R3).
* Procedures on R3, R4, R6, R7, and R8 are the same as discussed in
the example for "in-place update".
* Procedure on R9 is the same as discussed in the example for
"initial setup".
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* M-Path message processing on R2:
- R2 processes the JUNCTION, updates the JSB, adds a new JCT-
NHOP, and waits for an M-Resv message with the new version to
be received from each JCT-NHOP (R4, R5, and R9).
* M-Path message processing on R5:
- R5 processes the JUNCTION, updates the JSB, adds a new JCT-
PHOP, and waits for an M-Resv message with the new version to
be received from R8.
* M-Resv message processing on R5:
- R5 allocates a label for JCT-PHOP 9 and programs the
corresponding labeled route.
- R5 sends an M-Resv message with the new version to each JCT-
PHOP.
- R5 sends an M-Notify message to R1, indicating that the
junction update processing is complete on the node.
* M-Resv message processing on R2:
- R2 waits until M-Resv messages with the new version are
received from all available JCT-NHOPs and then:
o Reprograms the labeled routes to include JCT-NHOP 9 in the
list of next-hops.
o Sends an M-Resv message with the new version to each JCT-
PHOP.
o Sends an M-Notify message to R1, indicating that the
junction update processing is complete on R2.
* M-Notify message processing on the signaling source:
- The signaling source (R1) considers the update sequence
complete when confirmation of junction processing is received
from all junctions.
Authors' Addresses
Kompella, et al. Expires 23 April 2026 [Page 46]
Internet-Draft RSVP-TE for MPTE October 2025
Kireeti Kompella
Juniper Networks
Sunnyvale, California 94089
United States of America
Email: kireeti.ietf@gmail.com
Vishnu Pavan Beeram
Juniper Networks
Sunnyvale, CA 94089
United States of America
Email: vbeeram@juniper.net
Chandra Ramachandran
Juniper Networks
Bengaluru
India
Email: csekar@juniper.net
Kompella, et al. Expires 23 April 2026 [Page 47]