TEAS K. Kompella Internet-Draft V. P. Beeram Intended status: Standards Track C. Ramachandran Expires: 6 May 2027 HPE 2 November 2026 RSVP-TE Extensions for Multipath Traffic Engineered Directed Acyclic Graph Tunnels draft-kbr-teas-mptersvp-06 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 working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. 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 6 May 2027. Copyright Notice Copyright (c) 2026 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 Kompella, et al. Expires 6 May 2027 [Page 1] Internet-Draft RSVP-TE for MPTE November 2026 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 . . . . . . . . . . . . . . . . . . . . 7 2.2.1. JUNCTION . . . . . . . . . . . . . . . . . . . . . . 7 2.3. MPTED Signaling Source (SS) . . . . . . . . . . . . . . . 7 2.3.1. Versioning . . . . . . . . . . . . . . . . . . . . . 7 2.3.2. Label Allocation . . . . . . . . . . . . . . . . . . 8 2.3.3. JUNCTION State Block (JSB) . . . . . . . . . . . . . 8 2.3.4. Load-Shares and Bandwidth Reservation . . . . . . . . 8 2.3.5. Tunnel Status . . . . . . . . . . . . . . . . . . . . 10 2.3.6. In-Place Update vs Make-Before-Break . . . . . . . . 10 3. Signaling for Junction Management . . . . . . . . . . . . . . 11 3.1. Source to Junction (S2J) Messages . . . . . . . . . . . . 11 3.1.1. JunctionCreate . . . . . . . . . . . . . . . . . . . 11 3.1.2. JunctionUpdate . . . . . . . . . . . . . . . . . . . 11 3.1.3. JunctionDelete . . . . . . . . . . . . . . . . . . . 11 3.2. Junction to Source (J2S) Messages . . . . . . . . . . . . 12 3.2.1. JunctionNotify . . . . . . . . . . . . . . . . . . . 12 3.2.2. ResourceNotify . . . . . . . . . . . . . . . . . . . 12 3.3. Junction to Junction (J2J) Messages: . . . . . . . . . . 12 3.3.1. Upstream (J2JU) Messages . . . . . . . . . . . . . . 12 3.3.2. Downstream (J2JD) Messages . . . . . . . . . . . . . 13 4. RSVP Messages and Objects . . . . . . . . . . . . . . . . . . 13 4.1. MPTED Path (M-Path) Message . . . . . . . . . . . . . . . 13 4.2. MPTED Resv (M-Resv) Message . . . . . . . . . . . . . . . 14 4.3. MPTED PathTear (M-PathTear) Message . . . . . . . . . . . 15 4.4. MPTED Notify (M-Notify) Message . . . . . . . . . . . . . 16 4.5. ResourceNotify Message . . . . . . . . . . . . . . . . . 18 4.6. Objects . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.6.1. SESSION Object . . . . . . . . . . . . . . . . . . . 19 4.6.2. END_POINTS Object . . . . . . . . . . . . . . . . . . 20 4.6.3. DAG_INSTANCE Object . . . . . . . . . . . . . . . . . 22 4.6.4. JUNCTION Object . . . . . . . . . . . . . . . . . . . 23 4.6.5. JUNCTION_PHOPS Object . . . . . . . . . . . . . . . . 25 4.6.6. JUNCTION_NHOPS Object . . . . . . . . . . . . . . . . 31 Kompella, et al. Expires 6 May 2027 [Page 2] Internet-Draft RSVP-TE for MPTE November 2026 4.6.7. JUNCTION_HOP Object . . . . . . . . . . . . . . . . . 39 4.6.8. JUNCTION_LABELED_HOP Object . . . . . . . . . . . . . 40 4.6.9. JUNCTION_STATUS . . . . . . . . . . . . . . . . . . . 42 4.6.10. JUNCTION_HOP_STATUS . . . . . . . . . . . . . . . . . 45 4.6.11. CONDITIONS Object . . . . . . . . . . . . . . . . . . 46 5. Protection . . . . . . . . . . . . . . . . . . . . . . . . . 47 6. Graceful Restart . . . . . . . . . . . . . . . . . . . . . . 47 7. Security Considerations . . . . . . . . . . . . . . . . . . . 47 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 47 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 47 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 47 10.1. Normative References . . . . . . . . . . . . . . . . . . 47 10.2. Informative References . . . . . . . . . . . . . . . . . 48 Appendix A. Signaling Sequences - Examples . . . . . . . . . . . 49 A.1. Initial Setup Sequence . . . . . . . . . . . . . . . . . 49 A.2. Update Sequence - "In-Place" . . . . . . . . . . . . . . 51 A.3. Update Sequence - In-Place Add Junction . . . . . . . . . 53 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 55 1. Introduction The notions of Multipath Traffic Engineering (MPTE) and of an MPTE Directed Acyclic Graph (MPTED) tunnel are introduced in [I-D.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. Kompella, et al. Expires 6 May 2027 [Page 3] Internet-Draft RSVP-TE for MPTE November 2026 As discussed in [I-D.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. This version of the document focuses on how RSVP-TE is extended to provision MPTED tunnels in a distributed manner 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.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 Kompella, et al. Expires 6 May 2027 [Page 4] Internet-Draft RSVP-TE for MPTE November 2026 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, an MPTEC tunnel has exactly one ingress and 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). Kompella, et al. Expires 6 May 2027 [Page 5] Internet-Draft RSVP-TE for MPTE November 2026 2. Compute an MPTE DAG that satisfies the constraints. This function is undertaken by the MPTE Computer (MC). 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: . The MPTED OID is the IP (v4/v6) 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). Kompella, et al. Expires 6 May 2027 [Page 6] Internet-Draft RSVP-TE for MPTE November 2026 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 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 into the junction, a list of previous-hops (JCT-PHOPs), and a list of next-hops (JCT-NHOPs) with their load-shares (Section 2.3.4). 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 There are two levels of versioning associated with an MPTED tunnel: * DAG Instance ID: An unsigned 32-bit identifier (carried in the DAG_INSTANCE object) that identifies the instance of the MPTED tunnel's DAG. An MPTED tunnel instance is uniquely identified by the 3-tuple . The DAG Instance ID is managed by the SS. Kompella, et al. Expires 6 May 2027 [Page 7] Internet-Draft RSVP-TE for MPTE November 2026 * Hop Version: An unsigned 32-bit version number associated with each hop (JCT-PHOP or JCT-NHOP) within a JUNCTION. The Hop Version changes when there is an in-place update to the MPTED tunnel (e.g., a change in bandwidth or load shares). A change of the Junction Bandwidth is signaled together with a change of the Hop Version of every JCT-NHOP of the junction (of every JCT-PHOP, at a junction that has no JCT-NHOPs). The Hop Version is carried in each hop entry within the JUNCTION_PHOPS and JUNCTION_NHOPS objects. 2.3.2. Label Allocation [I-D.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. 2.3.4. Load-Shares and Bandwidth Reservation The JUNCTION object carries the Junction Bandwidth, and each JCT-NHOP carries a Bandwidth value that determines its load-share. The two are independent of each other. The Junction Bandwidth is the bandwidth to be admitted and reserved for the MPTED tunnel at the junction. A Junction Bandwidth of zero means that no bandwidth is reserved at the junction, for example when the DAG has no bandwidth constraint. The bandwidth going out of a junction is the Junction Bandwidth, distributed over the JCT-NHOPs as described below. It is not signaled separately. Kompella, et al. Expires 6 May 2027 [Page 8] Internet-Draft RSVP-TE for MPTE November 2026 The Bandwidth of a JCT-NHOP is encoded in the same format and units as the Junction Bandwidth (a 32-bit IEEE floating point number, in bytes per second). It can, for example, be the bandwidth that the DAG computation (such as a max-flow computation) assigns to that next hop. Only the ratio of the Bandwidth values of the JCT-NHOPs of a junction is used. The values need not add up to the Junction Bandwidth, and a non-zero value does not by itself cause a reservation. A junction node MUST NOT provision the junction from an M-Path message that carries a Junction Bandwidth or a JCT-NHOP Bandwidth that is not a finite, non-negative IEEE 754 binary32 value. Negative zero is treated as zero. As for any M-Path message that cannot be catered to, the junction node reports this in an M-Notify message (Section 4.4). A JCT-NHOP is active if the TE link toward it is available, the junction on it is not "Down", and either its Backup (B) flag is clear or it is a backup JCT-NHOP that is in use. Whether a backup JCT-NHOP is in use is local state of the junction node; it is not signaled. The conditions under which a backup JCT-NHOP is put into use will be specified in a future revision of this document. For forwarding, the effective load-share of an active JCT-NHOP is determined as follows: * If at least one active JCT-NHOP has a non-zero Bandwidth value, the effective load-share of an active JCT-NHOP is its Bandwidth value. In that case, a JCT-NHOP with a zero Bandwidth value is still a valid JCT-NHOP, but it receives no traffic. * If all active JCT-NHOPs have a zero Bandwidth value, the effective load-share of each active JCT-NHOP is 1, so that traffic is shared equally. A JCT-NHOP that is not active has an effective load-share of zero. A junction node sends traffic to each active JCT-NHOP in proportion to its effective load-share: JCT-NHOP n receives the fraction e(n) / sum(e(i)) of the traffic, where e(i) is the effective load-share of JCT-NHOP i. A node may quantize the ratios to the granularity of its forwarding plane, so the resulting split is approximate. Bandwidth is reserved only on the TE links toward the non-backup JCT- NHOPs. In this version of the document, no bandwidth is reserved toward a backup JCT-NHOP, including while it is in use, because traffic is expected to use a backup JCT-NHOP only temporarily. Reserving bandwidth toward backup JCT-NHOPs may be specified in a future revision. The reservation depends only on the signaled values and not on the operational state. The bandwidth reserved toward non- backup JCT-NHOP n is J x r(n) / sum(r(i)), where J is the Junction Kompella, et al. Expires 6 May 2027 [Page 9] Internet-Draft RSVP-TE for MPTE November 2026 Bandwidth, r(i) is the Bandwidth value of non-backup JCT-NHOP i, and the sum is over all non-backup JCT-NHOPs. If all of those values are zero, r(i) is 1 for each of them. If J is zero, no bandwidth is reserved, bandwidth admission is not performed, and the Reserved Bandwidth reported for each JCT-NHOP is zero. In this version of the document, the Reserved Bandwidth reported for a backup JCT-NHOP is zero. No traffic is sent toward a JCT-NHOP that is "Down", so the bandwidth reserved toward it is not in use. The reservations toward the other JCT-NHOPs are not changed, and the signaled Bandwidth values are not reprogrammed until a new M-Path message updates them. In the meantime, the traffic is shared among the active JCT-NHOPs in proportion to their signaled Bandwidth values. A JSB-NHOP that has been marked as a candidate for deletion is not a JCT-NHOP of the updated state. It is excluded from the effective load-shares and from the reservation computation above. It continues to forward traffic using its previous state until it is deleted. 2.3.5. 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. 2.3.6. In-Place Update vs Make-Before-Break Updates to an MPTED tunnel may be carried out in-place or via a make- before-break approach. Either approach may be used regardless of whether the shape of the DAG has changed. An in-place update directly modifies the existing JUNCTION state on the junction nodes. A make-before-break update establishes a new DAG instance before tearing down the old one. This approach is typically useful in scenarios where there is a need to clear the existing instance. Kompella, et al. Expires 6 May 2027 [Page 10] Internet-Draft RSVP-TE for MPTE November 2026 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. 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 carries a DAG Instance ID (in the DAG_INSTANCE object) and per-hop versions (in the hop entries) that together identify the instance of the "JUNCTION" being created. This document uses the RSVP MPTED Path (M-Path) message as the 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 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 in place until explicitly instructed to do so. This document uses the RSVP MPTED Path (M-Path) message as the 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. Kompella, et al. Expires 6 May 2027 [Page 11] Internet-Draft RSVP-TE for MPTE November 2026 This document uses the RSVP MPTED PathTear (M-PathTear) message as the 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. This document uses the RSVP MPTED Notify (M-Notify) message as the 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 uses the RSVP ResourceNotify message defined in [I-D.beeram-teas-rsvp-resource-notifications] as the 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 uses the RSVP MPTED Resv (M-Resv) message as the J2JU JunctionNextHopReservation message. Kompella, et al. Expires 6 May 2027 [Page 12] Internet-Draft RSVP-TE for MPTE November 2026 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 uses the RSVP M-Notify message as the 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. This document uses the RSVP M-PathTear message as the 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 (DAG_INSTANCE 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 load-shares (Section 2.3.4) () 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 Hop Version change, it updates the corresponding JSB using the information encoded in the message. The JSB update may Kompella, et al. Expires 6 May 2027 [Page 13] Internet-Draft RSVP-TE for MPTE November 2026 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. 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. ::= [] [ [ | ] ... ] [ ] [] ::= ::= ( | | ( )) 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 (DAG_INSTANCE 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 Kompella, et al. Expires 6 May 2027 [Page 14] Internet-Draft RSVP-TE for MPTE November 2026 the tunnel signaling source. No message is sent out until M-Resv messages from all available JCT-NHOPs have been received and processed. The bandwidth admitted on the TE link toward each JCT- NHOP is determined as described in Section 2.3.4. 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. The bandwidth admitted on the TE link toward each JCT-NHOP is determined as described in Section 2.3.4. ::= [ ] [ [ | ] ... ] [ ] ::= [ ] 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 (DAG_INSTANCE 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 (DAG_INSTANCE Object) Kompella, et al. Expires 6 May 2027 [Page 15] Internet-Draft RSVP-TE for MPTE November 2026 * Hop identifier (JUNCTION_HOP Object) During the make-before-break update of an MPTED tunnel, when a junction node completes updating all JCT-PHOPs matching the new DAG Instance ID, 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 DAG Instance ID. 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. ::= [ ] [ [ | ] ... ] [ ] [ ] | [ ] 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 (DAG_INSTANCE Object) * MTU (JUNCTION_STATUS Object) * Status (JUNCTION_STATUS Object) If the Status is "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" (using PHOP Label_Status TLVs, Type 0x05/0x06) Kompella, et al. Expires 6 May 2027 [Page 16] Internet-Draft RSVP-TE for MPTE November 2026 * List of JCT-NHOPs that are "Down/Degraded" and the reserved bandwidth on each corresponding TE link (using NHOP Label_Status TLVs, Type 0x05/0x06) If a junction node cannot provision the junction as requested by an M-Path message, the M-Notify message that it sends in response conveys, through the Status and the additional information above, that the junction was not provisioned as requested. The Label_Status TLVs (Type 0x05 for IPv4, Type 0x06 for IPv6) are used in the JUNCTION_PHOPS and JUNCTION_NHOPS objects within the M-Notify message to report status changes of labeled hops. 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 (DAG_INSTANCE 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 treats the JCT-NHOP as not active (Section 2.3.4) and reprograms the labeled routes. If no JCT-NHOP remains active, the junction is itself "Down" and the node notifies its upstream junction nodes. ::= [] [ [ | ] ... ] [ ] ( | ) ::= [ ] ::= ( | | ( )) Kompella, et al. Expires 6 May 2027 [Page 17] Internet-Draft RSVP-TE for MPTE November 2026 4.5. ResourceNotify Message A ResourceNotify message is a J2S message that is used to notify the tunnel signaling source of the unavailability or degradation of a TE link. The message, the RESOURCE_SPEC and DEG_RESOURCE_SPEC objects that it carries, and the procedures for generating, acknowledging and processing it, including the fallback and security procedures, are defined in [I-D.beeram-teas-rsvp-resource-notifications] and are not repeated here. This section describes how that document applies to RSVP MPTED tunnels. In the terms of [I-D.beeram-teas-rsvp-resource-notifications]: * The junction node is the transit node that generates ResourceNotify messages. The TE links of interest are the TE links that the junction node uses toward the JCT-NHOPs of the MPTED tunnels for which it holds junction state. * The tunnel signaling source is the Notify-Requester. A junction node determines its address from the Signaling Source ID in the DAG_INSTANCE object or, when the DAG_INSTANCE object does not carry one, from the sender of the M-Path message. * A Notify-Requester does not use the Resource Notification Request Object. This document defines an implicit procedure for requesting Resource Notifications: the receipt of an M-Path message at a junction node that supports [I-D.beeram-teas-rsvp-resource-notifications] is sufficient to indicate that the signaling source requires Resource Notifications for the MPTED tunnel. * An MPTED tunnel takes the place of an LSP. The set of MPTED tunnels associated with a Notify-Requester is the set of MPTED tunnels that it signals and for which the junction node holds junction state. * Where [I-D.beeram-teas-rsvp-resource-notifications] calls for per- LSP PathErr notifications, a junction node sends J2S M-Notify messages (Section 4.4) for the affected junctions instead. When a TE link goes down, the junction node sends a ResourceNotify message to each impacted tunnel signaling source to notify it 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 Kompella, et al. Expires 6 May 2027 [Page 18] Internet-Draft RSVP-TE for MPTE November 2026 this scenario, the information carried in the ResourceNotify 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. Once a ResourceNotify message for a TE link has been acknowledged, the junction node does not send M-Notify messages to that signaling source to report the same resource event for the affected junctions, unless a condition for the fallback procedure applies. The junction node adapts its own state to the event as described in Section 2.3.4, independently of the ResourceNotify message. Upon receiving a ResourceNotify message, a tunnel signaling source determines the MPTED tunnels, and the junctions of those tunnels, that use the identified TE link, and reacts as it would to a junction that is reported "Down" or "Degraded" in an M-Notify message. For a degraded TE link, it reduces the bandwidth that its MPTED tunnels use on the link by at least the indicated amount, for example by reducing the Junction Bandwidth of the affected junctions. 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. Kompella, et al. Expires 6 May 2027 [Page 19] Internet-Draft RSVP-TE for MPTE November 2026 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 Kompella, et al. Expires 6 May 2027 [Page 20] Internet-Draft RSVP-TE for MPTE November 2026 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: Kompella, et al. Expires 6 May 2027 [Page 21] Internet-Draft RSVP-TE for MPTE November 2026 - 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. DAG_INSTANCE Object Class = DAG_INSTANCE, DAG_INSTANCE 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DAG Instance ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * DAG Instance ID: - Identifies the current instance of the MPTED tunnel's DAG topology. This C-Type is used when the MPTED tunnel originator is also the signaling source. In this case, the node sending the M-Path message is implicitly deemed to be the signaling source. Class = DAG_INSTANCE, DAG_INSTANCE_SS_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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DAG Instance ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Signaling Source ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * DAG Instance ID: - Identifies the current instance of the MPTED tunnel's DAG topology. * Signaling Source ID: Kompella, et al. Expires 6 May 2027 [Page 22] Internet-Draft RSVP-TE for MPTE November 2026 - IPv4 address of the MPTED tunnel signaling source. This C-Type is used if the MPTED tunnel originator is different from the signaling source. Class = DAG_INSTANCE, DAG_INSTANCE_SS_v6 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DAG Instance ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Signaling Source ID (16 bytes) | | | | ....... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * DAG Instance ID: - Identifies the current instance of the MPTED tunnel's DAG topology. * Signaling Source ID: - IPv6 address of the MPTED tunnel signaling source. This C-Type is used if the MPTED tunnel originator is different from the signaling source. 4.6.4. JUNCTION Object 4.6.4.1. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DAG Instance ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Bandwidth (32-bit IEEE floating point number) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Junction ID: - IPv4 address of the junction node. Kompella, et al. Expires 6 May 2027 [Page 23] Internet-Draft RSVP-TE for MPTE November 2026 * DAG Instance ID: - Identifier of the DAG instance. This value matches the DAG Instance ID carried in the DAG_INSTANCE object. * Bandwidth: - Bandwidth to be reserved for the MPTED tunnel at the junction, i.e., the bandwidth coming into the junction node (encoded as a 32-bit IEEE floating point number). The units are bytes per second. A value of zero indicates that no bandwidth is reserved (Section 2.3.4). 4.6.4.2. JUNCTION_IPv6 Class = JUNCTION, JUNCTION_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) | | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DAG Instance ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Bandwidth (32-bit IEEE floating point number) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Junction ID: - IPv6 address of the junction node. * DAG Instance ID: - Identifier of the DAG instance. This value matches the DAG Instance ID carried in the DAG_INSTANCE object. * Bandwidth: - Bandwidth to be reserved for the MPTED tunnel at the junction, i.e., the bandwidth coming into the junction node (encoded as a 32-bit IEEE floating point number). The units are bytes per second. A value of zero indicates that no bandwidth is reserved (Section 2.3.4). Kompella, et al. Expires 6 May 2027 [Page 24] Internet-Draft RSVP-TE for MPTE November 2026 4.6.5. 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. 4.6.5.1. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * 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). Kompella, et al. Expires 6 May 2027 [Page 25] Internet-Draft RSVP-TE for MPTE November 2026 * Hop Version: - Version of the hop. 4.6.5.2. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 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: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. * Label: - Assigned label for the PHOP. Kompella, et al. Expires 6 May 2027 [Page 26] Internet-Draft RSVP-TE for MPTE November 2026 4.6.5.3. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * 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). * Hop Version: - Version of the hop. 4.6.5.4. JUNCTION_PHOP_IPv6_Label TLV Kompella, et al. Expires 6 May 2027 [Page 27] Internet-Draft RSVP-TE for MPTE November 2026 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 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). * Hop Version: - Version of the hop. * Label: - Assigned label for the PHOP. 4.6.5.5. JUNCTION_PHOP_IPv4_Label_Status TLV Kompella, et al. Expires 6 May 2027 [Page 28] Internet-Draft RSVP-TE for MPTE November 2026 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | MTU | Flags | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Type: - 0x05 Series of IPv4 PHOPs with label and status. * 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: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. * Label: - Assigned label for the PHOP. * MTU: - Path MTU from this previous hop. * Flags: Kompella, et al. Expires 6 May 2027 [Page 29] Internet-Draft RSVP-TE for MPTE November 2026 - Status flags: o 0x01 Up (U): PHOP is operational. o 0x02 Down (D): PHOP is down. o 0x04 Degraded (G): PHOP is in a degraded state. 4.6.5.6. JUNCTION_PHOP_IPv6_Label_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 | Rsvd | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv6 Peer Address (16 bytes) | | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer Interface Index | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | MTU | Flags | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Type: - 0x06 Series of IPv6 PHOPs with label and status. * 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). * Hop Version: Kompella, et al. Expires 6 May 2027 [Page 30] Internet-Draft RSVP-TE for MPTE November 2026 - Version of the hop. * Label: - Assigned label for the PHOP. * MTU: - Path MTU from this previous hop. * Flags: - Status flags: o 0x01 Up (U): PHOP is operational. o 0x02 Down (D): PHOP is down. o 0x04 Degraded (G): PHOP is in a degraded state. 4.6.6. 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: - The contents of a JUNCTION_NHOPS object are a series of TLVs. 4.6.6.1. JUNCTION_NHOP_IPv4 TLV Kompella, et al. Expires 6 May 2027 [Page 31] Internet-Draft RSVP-TE for MPTE November 2026 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Bandwidth | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * 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. All other bits are reserved. They MUST be set to zero on transmission and ignored on receipt. * IPv4 Peer Address: - IPv4 address of the next hop (remote end of the TE link). * Peer Interface Index: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. * Bandwidth: Kompella, et al. Expires 6 May 2027 [Page 32] Internet-Draft RSVP-TE for MPTE November 2026 - The bandwidth that determines the load-share of this next hop (encoded as a 32-bit IEEE floating point number). The units are bytes per second. Only the ratio of the Bandwidth values of the next hops of a junction is used, as described in Section 2.3.4. The value does not by itself cause a bandwidth reservation. 4.6.6.2. JUNCTION_NHOP_IPv4_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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv4 Peer Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer Interface Index | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | 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. All other bits are reserved. They MUST be set to zero on transmission and ignored on receipt. * IPv4 Peer Address: - IPv4 address of the next hop (remote end of the TE link). Kompella, et al. Expires 6 May 2027 [Page 33] Internet-Draft RSVP-TE for MPTE November 2026 * Peer Interface Index: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. * MTU: - MTU value received from the next-hop. * 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. 4.6.6.3. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Bandwidth | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Type: - 0x03 Series of IPv6 NHOPs. * Length: - Total length of the TLV. It varies based on the number of IPv6 NHOPs encoded. * Flags: Kompella, et al. Expires 6 May 2027 [Page 34] Internet-Draft RSVP-TE for MPTE November 2026 - 0x01 Backup (B): Presence of this flag denotes the specified next-hop as a backup next-hop. All other bits are reserved. They MUST be set to zero on transmission and ignored on receipt. * IPv6 Peer Address: - IPv6 address of the next hop (remote end of the TE link). * Peer Interface Index: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. * Bandwidth: - The bandwidth that determines the load-share of this next hop (encoded as a 32-bit IEEE floating point number). The units are bytes per second. Only the ratio of the Bandwidth values of the next hops of a junction is used, as described in Section 2.3.4. The value does not by itself cause a bandwidth reservation. 4.6.6.4. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | MTU | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved Bandwidth (32-bit IEEE floating point number) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Kompella, et al. Expires 6 May 2027 [Page 35] Internet-Draft RSVP-TE for MPTE November 2026 * 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. All other bits are reserved. They MUST be set to zero on transmission and ignored on receipt. * IPv6 Peer Address: - IPv6 address of the next hop (remote end of the TE link). * Peer Interface Index: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. * MTU: - MTU value received from the next-hop. * 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. 4.6.6.5. JUNCTION_NHOP_IPv4_Label_Status TLV Kompella, et al. Expires 6 May 2027 [Page 36] Internet-Draft RSVP-TE for MPTE November 2026 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | MTU | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved Bandwidth (32-bit IEEE floating point number) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Type: - 0x05 Series of IPv4 NHOP Label and Statuses. * Length: - Total length of the TLV. It varies based on the number of IPv4 NHOP label-statuses encoded. * Flags: - 0x01 Backup (B): Presence of this flag denotes the specified next-hop as a backup next-hop. All other bits are reserved. They MUST be set to zero on transmission and ignored on receipt. * IPv4 Peer Address: - IPv4 address of the next hop (remote end of the TE link). * Peer Interface Index: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. Kompella, et al. Expires 6 May 2027 [Page 37] Internet-Draft RSVP-TE for MPTE November 2026 * MTU: - MTU value received from the next-hop. * 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. * Label: - Downstream label assigned by the next-hop. 4.6.6.6. JUNCTION_NHOP_IPv6_Label_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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | MTU | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved Bandwidth (32-bit IEEE floating point number) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Type: - 0x06 Series of IPv6 NHOP Label and Statuses. * Length: - Total length of the TLV. It varies based on the number of IPv6 NHOP label-statuses encoded. * Flags: Kompella, et al. Expires 6 May 2027 [Page 38] Internet-Draft RSVP-TE for MPTE November 2026 - 0x01 Backup (B): Presence of this flag denotes the specified next-hop as a backup next-hop. All other bits are reserved. They MUST be set to zero on transmission and ignored on receipt. * IPv6 Peer Address: - IPv6 address of the next hop (remote end of the TE link). * Peer Interface Index: - Index of the peer interface (remote end of the TE link). * Hop Version: - Version of the hop. * MTU: - MTU value received from the next-hop. * 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. * Label: - Downstream label assigned by the next-hop. 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 Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Hop Address: Kompella, et al. Expires 6 May 2027 [Page 39] Internet-Draft RSVP-TE for MPTE November 2026 - IPv4 address of the hop of interest. * Hop Interface Index: - Interface index of the hop of interest. * Hop Version: - Version of the hop. Class = JUNCTION_HOP, JUNCTION_HOP_v6 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Hop Address: - IPv6 address of the hop of interest. * Hop Interface Index: - Interface index of the hop of interest. * Hop Version: - Version of the hop. 4.6.8. JUNCTION_LABELED_HOP Object Class = JUNCTION_LABELED_HOP, JUNCTION_LABELED_HOP_IPv4 C-Type = TBD Kompella, et al. Expires 6 May 2027 [Page 40] Internet-Draft RSVP-TE for MPTE November 2026 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 Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | MTU | Res | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Hop Address: - IPv4 address of the hop of interest. * Hop Interface Index: - Interface index of the hop of interest. * Hop Version: - Version of the hop. * MTU: - MTU value associated with the specified hop. * Label: - Label associated with the specified hop. Class = JUNCTION_LABELED_HOP, JUNCTION_LABELED_HOP_IPv6 C-Type = TBD Kompella, et al. Expires 6 May 2027 [Page 41] Internet-Draft RSVP-TE for MPTE November 2026 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 Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | MTU | Res | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Label | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Hop Address: - IPv6 address of the hop of interest. * Hop Interface Index: - Interface index of the hop of interest. * Hop Version: - Version of the hop. * MTU: - MTU value associated with the specified hop. * Label: - Label associated with the specified hop. 4.6.9. 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: Kompella, et al. Expires 6 May 2027 [Page 42] Internet-Draft RSVP-TE for MPTE November 2026 - IPv4 address of the junction node. * MTU: - MTU of the junction node. * Flags: - 0x01 Up (U): Junction is operational. - 0x02 Down (D): Junction is down. - 0x04 Degraded (G): Junction is in a degraded state. 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: - 0x01 Up (U): Junction is operational. - 0x02 Down (D): Junction is down. - 0x04 Degraded (G): Junction is in a degraded state. Class = JUNCTION_STATUS, JUNCTION_STATUS_Degraded_IPv4 C-Type = TBD Kompella, et al. Expires 6 May 2027 [Page 43] Internet-Draft RSVP-TE for MPTE November 2026 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: - 0x01 Up (U): Junction is operational. - 0x02 Down (D): Junction is down. - 0x04 Degraded (G): Junction is in a degraded state. * 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 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. Kompella, et al. Expires 6 May 2027 [Page 44] Internet-Draft RSVP-TE for MPTE November 2026 * MTU: - MTU of the junction node. * Flags: - 0x01 Up (U): Junction is operational. - 0x02 Down (D): Junction is down. - 0x04 Degraded (G): Junction is in a degraded state. * Reserved Bandwidth: - Bandwidth reserved for the junction (encoded as a 32-bit IEEE floating point number). 4.6.10. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Res | Flags | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Hop Address: - IPv4 address of the hop of interest. * Hop Index: - Interface index of the hop of interest. * Hop Version: - Version of the hop. * Flags: - 0x01 Up (U): Hop is operational. Kompella, et al. Expires 6 May 2027 [Page 45] Internet-Draft RSVP-TE for MPTE November 2026 - 0x02 Down (D): Hop is down. - 0x04 Degraded (G): Hop is in a degraded state. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Hop Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Res | Flags | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * Hop Address: - IPv6 address of the hop of interest. * Hop Index: - Interface index of the hop of interest. * Hop Version: - Version of the hop. * Flags: - 0x01 Up (U): Hop is operational. - 0x02 Down (D): Hop is down. - 0x04 Degraded (G): Hop is in a degraded state. 4.6.11. CONDITIONS Object Class = 135 (CONDITIONS), C-Type = 1 The CONDITIONS object is defined in [RFC9705]. This document extends the use of the CONDITIONS object by defining a new flag bit. Kompella, et al. Expires 6 May 2027 [Page 46] Internet-Draft RSVP-TE for MPTE November 2026 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: - M-Bit (Bit 31): Merge-point condition bit as defined in [RFC9705]. - J-Bit (Bit 30): Propagate the deletion request downstream. 5. Protection (To be added in a later revision.) 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 and discussions. 10. References 10.1. Normative References [I-D.beeram-teas-rsvp-resource-notifications] Beeram, V. P. and C. Ramachandran, "RSVP-TE Resource Notifications", Work in Progress, Internet-Draft, draft- beeram-teas-rsvp-resource-notifications-00, November 2026, . [I-D.kompella-teas-mpte] Kompella, K., Jalil, L., Khaddam, M., Geyer, N., and A. J. Smith, "Multipath Traffic Engineering", Work in Progress, Kompella, et al. Expires 6 May 2027 [Page 47] Internet-Draft RSVP-TE for MPTE November 2026 Internet-Draft, draft-kompella-teas-mpte-04, October 2026, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [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, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . 10.2. Informative References [I-D.kompella-lsr-mptecap] Kompella, K., "Multipath Traffic Engineering Capabilities", Work in Progress, Internet-Draft, draft- kompella-lsr-mptecap-02, July 2026, . [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, . [RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation Element (PCE) Communication Protocol (PCEP)", RFC 5440, DOI 10.17487/RFC5440, March 2009, . [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, . Kompella, et al. Expires 6 May 2027 [Page 48] Internet-Draft RSVP-TE for MPTE November 2026 [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, . [RFC9705] Ramachandran, C., Saad, T., and D. Pacella, "Refresh- Interval Independent RSVP Fast Reroute Facility Protection", RFC 9705, DOI 10.17487/RFC9705, March 2025, . Appendix A. Signaling Sequences - Examples A.1. Initial Setup Sequence 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: Kompella, et al. Expires 6 May 2027 [Page 49] Internet-Draft RSVP-TE for MPTE November 2026 - 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. - 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 waits 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. Kompella, et al. Expires 6 May 2027 [Page 50] Internet-Draft RSVP-TE for MPTE November 2026 * 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" 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: Kompella, et al. Expires 6 May 2027 [Page 51] Internet-Draft RSVP-TE for MPTE November 2026 - R1 sends an M-Path message with a new Hop 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 Hop Version to arrive from each JCT-NHOP. * M-Path message processing on egress junction node, R8: - R8 processes the JUNCTION and updates the JSB. - R8 sends an M-Resv message with the new Hop 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 Hop 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 Hop 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 waits until M-Resv messages with the new Hop 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) Kompella, et al. Expires 6 May 2027 [Page 52] Internet-Draft RSVP-TE for MPTE November 2026 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 - In-Place Add Junction +---+ 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 - In-Place Add Junction * Initiation of update sequence on MPTED signaling source, R1: Kompella, et al. Expires 6 May 2027 [Page 53] Internet-Draft RSVP-TE for MPTE November 2026 - R1 sends an M-Path message with a new Hop 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". * 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 Hop 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 Hop 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 Hop 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 Hop 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 Hop Version to each JCT-PHOP. Kompella, et al. Expires 6 May 2027 [Page 54] Internet-Draft RSVP-TE for MPTE November 2026 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 Kireeti Kompella HPE Sunnyvale, California 94089 United States of America Email: kireeti.ietf@gmail.com Vishnu Pavan Beeram HPE Sunnyvale, CA 94089 United States of America Email: vishnupavan.ietf@gmail.com Chandra Ramachandran HPE Bengaluru India Email: chandrasekar.ramachandran@hpe.com Kompella, et al. Expires 6 May 2027 [Page 55]