mLDP Extensions for Multi-Topology Routing
draft-ietf-mpls-mldp-multi-topology-09
The information below is for an old version of the document that is already published as an RFC.
| Document | Type |
This is an older version of an Internet-Draft that was ultimately published as RFC 9658.
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|
|---|---|---|---|
| Authors | IJsbrand Wijnands , Mankamana Prasad Mishra , Syed Kamran Raza , Zhaohui (Jeffrey) Zhang , Arkadiy Gulko | ||
| Last updated | 2024-10-28 (Latest revision 2024-05-21) | ||
| Replaces | draft-wijnands-mpls-mldp-multi-topology | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Proposed Standard | ||
| Formats | |||
| Reviews |
GENART IETF Last Call review
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Has issues
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| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Tarek Saad | ||
| Shepherd write-up | Show Last changed 2023-09-18 | ||
| IESG | IESG state | Became RFC 9658 (Proposed Standard) | |
| Action Holders |
(None)
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| Consensus boilerplate | Yes | ||
| Telechat date | (None) | ||
| Responsible AD | Jim Guichard | ||
| Send notices to | tsaad.net@gmail.com | ||
| IANA | IANA review state | IANA OK - Actions Needed | |
| IANA action state | RFC-Ed-Ack |
draft-ietf-mpls-mldp-multi-topology-09
MPLS Working Group IJ. Wijnands
Internet-Draft Individual
Updates: 7307 (if approved) M. Mishra (Editor)
Intended status: Standards Track K. Raza
Expires: 21 November 2024 Cisco Systems, Inc.
Z. Zhang
Juniper Networks
A. Gulko
Edward Jones wealth management
20 May 2024
mLDP Extensions for Multi-Topology Routing
draft-ietf-mpls-mldp-multi-topology-09
Abstract
Multi-Topology Routing (MTR) is a technology to enable service
differentiation within an IP network. Flexible Algorithm (FA) is
another mechanism of creating a sub-topology within a topology using
defined topology constraints and computation algorithm. In order to
deploy mLDP (Multipoint label distribution protocol) in a network
that supports MTR, FA, or other methods of signaling non-default IGP
algorithms, mLDP is required to become topology and algorithm aware.
This document specifies extensions to mLDP to support MTR, with an
algorithm, in order for Multipoint LSPs(Label Switched Paths) to
follow a particular topology and algorithm. It updates [RFC7307] by
allocating eight bits from a previously reserved field to be used as
the IGP Algorithm (IPA) field.
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 21 November 2024.
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Copyright Notice
Copyright (c) 2024 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
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. Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Specification of Requirements . . . . . . . . . . . . . . . . 4
4. MT Scoped mLDP FECs . . . . . . . . . . . . . . . . . . . . . 4
4.1. MP FEC Extensions for MT . . . . . . . . . . . . . . . . 5
4.1.1. MP FEC Element . . . . . . . . . . . . . . . . . . . 5
4.1.2. MT IP Address Families . . . . . . . . . . . . . . . 6
4.1.3. MT MP FEC Element . . . . . . . . . . . . . . . . . . 6
4.2. Topology IDs . . . . . . . . . . . . . . . . . . . . . . 7
5. MT Multipoint Capability . . . . . . . . . . . . . . . . . . 8
6. MT Applicability on FEC-based features . . . . . . . . . . . 9
6.1. Typed Wildcard MP FEC Elements . . . . . . . . . . . . . 9
6.2. End-of-LIB . . . . . . . . . . . . . . . . . . . . . . . 10
7. Topology-Scoped Signaling and Forwarding . . . . . . . . . . 10
7.1. Upstream LSR selection . . . . . . . . . . . . . . . . . 10
7.2. Downstream forwarding interface selection . . . . . . . . 10
8. LSP Ping Extensions . . . . . . . . . . . . . . . . . . . . . 11
9. Implementation Status . . . . . . . . . . . . . . . . . . . . 11
9.1. Cisco Systems . . . . . . . . . . . . . . . . . . . . . . 12
10. Security Considerations . . . . . . . . . . . . . . . . . . . 12
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
12. Contributor . . . . . . . . . . . . . . . . . . . . . . . . . 13
13. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13
14. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
14.1. Normative References . . . . . . . . . . . . . . . . . . 13
14.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Glossary
FA - Flexible Algorithm
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FEC - Forwarding Equivalence Class
IGP - Interior Gateway Protocol
IPA - IGP Algorithm
LDP - Label Distribution Protocol
LSP - Label Switched Path
mLDP - Multipoint LDP
MP - Multipoint (P2MP or MP2MP)
MP2MP - Multipoint-to-Multipoint
MT - Multi-Topology
MT-ID - Multi-Topology Identifier
MTR - Multi-Topology Routing
MVPN - Multicast over Virtual Private Network defined in section
2.3 of [RFC6513]
P2MP - Point-to-Multipoint
PMSI - Provider Multicast Service Interfaces [RFC6513]
2. Introduction
Multi-Topology Routing (MTR) is a technology to enable service
differentiation within an IP network. IGP protocols (OSPF and IS-IS)
and LDP have already been extended to support MTR. To support MTR,
an IGP maintains independent IP topologies, termed as "Multi-
Topologies" (MT), and computes/installs routes per topology. OSPF
extensions [RFC4915] and IS-IS extensions [RFC5120] specify the MT
extensions under respective IGPs. To support IGP MT, similar LDP
extensions [RFC7307] have been specified to make LDP MT-aware and be
able to setup unicast Label Switched Paths (LSPs) along IGP MT
routing paths.
A more lightweight mechanism to define constraint-based topologies is
the Flexible Algorithm (FA) [RFC9350]. FA can be seen as creating a
sub-topology within a topology using defined topology constraints and
computation algorithms. This can be done within an MTR topology or
the default Topology. An instance of such a sub-topology is
identified by a 1 octet value (Flex-Algorithm) as documented in
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[RFC9350]. A flexible Algorithm is a mechanism to create a sub-
topology, but in the future, different algorithms might be defined
for how to achieve that. For that reason, in the remainder of this
document, we'll refer to this as the IGP Algorithm. The IGP
Algorithm (IPA) Field Section 4.1.2 Section 6.1 is an 8-bit
identifier for the algorithm. The permissible values are tracked in
the IANA IGP Algorithm Types registry [IANA-IGP-ALGO-TYPES].
Throughout this document, the term Flexible Algorithm (FA) shall
denote the process of generating a sub-topology and signaling it
through Interior Gateway Protocol (IGP). However, it is essential to
note that the procedures outlined in this document are not
exclusively applicable to Flexible Algorithm but are extendable to
any non-default algorithm as well.
Multipoint LDP (mLDP) refers to extensions in LDP to setup multi-
point LSPs (point-to-multipoint (P2MP) or multipoint-to-multipoint
(MP2MP)), by means of a set of extensions and procedures defined in
[RFC6388]. In order to deploy mLDP in a network that supports MTR
and FA, mLDP is required to become topology and algorithm aware.
This document specifies extensions to mLDP to support MTR/IGP
Algorithm such that when building a Multi-Point LSPs it can follow a
particular topology and algorithm. This means that the identifier
for the particular topology to be used by mLDP have to become a
2-tuple (MTR Topology Id, IGP Algorithm).
3. Specification of Requirements
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.
4. MT Scoped mLDP FECs
As defined in [RFC7307], MPLS Multi-Topology Identifier (MT-ID) is an
identifier that is used to associate an LSP with a certain MTR
topology. In the context of MP LSPs, this identifier is part of the
mLDP FEC encoding so that LDP peers are able to setup an MP LSP via
their own defined MTR policy. In order to avoid conflicting MTR
policies for the same mLDP FEC, the MT-ID needs to be a part of the
FEC, so that different MT-ID values will result in unique MP-LSP FEC
elements.
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The same applies to the IGP Algorithm. The IGP Algorithm needs to be
encoded as part of the mLDP FEC to create unique MP-LSPs. The IGP
Algorithm is also used to signal to mLDP (hop-by-hop) which Algorithm
needs to be used to create the MP-LSP.
Since the MT-ID and IGP Algorithm are part of the FEC, they apply to
all the LDP messages that potentially include an mLDP FEC element.
4.1. MP FEC Extensions for MT
The following subsections define the extensions to bind an mLDP FEC
to a topology. These mLDP MT extensions reuse some of the extensions
specified in [RFC7307].
4.1.1. MP FEC Element
Base mLDP specification [RFC6388] defines MP FEC Element as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MP FEC type | Address Family | AF Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Root Node Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Opaque Length | Opaque Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: MP FEC Element Format [RFC6388]
Where the "Root Node Address" encoding is defined according to the
given "Address Family" with its length (in octets) specified by the
"AF Length" field.
To extend MP FEC elements for MT, the {MT-ID, IPA} tuple is relevant
in the context of the root address of the MP LSP. This tuple
determines the (sub)-topology in which the root address needs to be
resolved. As the {MT-ID, IPA} tuple should be considered part of the
mLDP FEC, it is most naturally encoded as part of the root address.
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4.1.2. MT IP Address Families
[RFC7307] specifies new address families, named "MT IP" and "MT
IPv6," to allow for the specification of an IP prefix within a
topology scope. In addition to using these address families for
mLDP, 8 bits of the 16-bit Reserved field are utilized to encode the
IGP Algorithm. The resulting format of the data associated with
these new Address Families is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | IPA | MT-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Address |
| |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | IPA | MT-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Modified MT IP Address Families Data Format
Where:
IPv4/IPv6 Address: An IP address corresponding to "MT IP" and "MT
IPv6" address families respectively.
IPA: The IGP Algorithm.
Reserved: This 8-bit field MUST be zero on transmission and MUST
be ignored on receipt.
4.1.3. MT MP FEC Element
By using the extended MT IP Address Family, the resulting MT MP FEC
element should be encoded as follows:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MP FEC type | AF (MT IP/ MT IPv6) | AF Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Root Node Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | IPA | MT-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Opaque Length | Opaque Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: IP MT-Scoped MP FEC Element Format
In the context of this document, the applicable LDP FECs for MT mLDP
([RFC6388]) include:
* MP FEC Elements:
- P2MP (type 0x6)
- MP2MP-up (type 0x7)
- MP2MP-down (type 0x8)
* Typed Wildcard FEC Element (type 0x5 defined in [RFC5918] )
In case of "Typed Wildcard FEC Element", the FEC Element type MUST be
one of the MP FECs listed above.
This specification allows the use of Topology-scoped mLDP FECs in LDP
label and notification messages, as applicable.
[RFC6514] defines the PMSI tunnel attribute for MVPN, and specifies
that when the Tunnel Type is set to mLDP P2MP LSP, the Tunnel
Identifier is a P2MP FEC Element, and when the Tunnel Type is set to
mLDP Multipoint-to-Multipoint (MP2MP) LSP, the Tunnel Identifier is
an MP2MP FEC Element. When the extension defined in this
specification is in use, the "IP MT-Scoped MP FEC Element Format"
form of the respective FEC elements MUST be used in these two cases.
4.2. Topology IDs
This document assumes the same definitions and procedures associated
with MPLS MT-ID as specified in [RFC7307] specification.
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5. MT Multipoint Capability
The "MT Multipoint Capability" is a new LDP capability, defined in
accordance with the LDP Capability definition guidelines outlined in
[RFC5561]. An mLDP speaker advertises this capability to its peers
to announce its support for MTR and the procedures specified in this
document. This capability MAY be sent either in an Initialization
message at session establishment or dynamically during the session's
lifetime via a Capability message, provided that the "Dynamic
Announcement" capability from [RFC5561] has been successfully
negotiated with the peer.
The format of this capability is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| MT Multipoint Capability | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S| Reserved |
+-+-+-+-+-+-+-+-+
Figure 4: MT Multipoint Capability TLV Format
Where:
U- and F-bits: MUST be 1 and 0, respectively, as per Section 3 of
LDP Capabilities [RFC5561].
MT Multipoint Capability: TLV type.
Length: The length (in octets) of TLV. The value of this field
MUST be 1 as there is no Capability-specific data [RFC5561] that
follows in the TLV. Length: This field specifies the length of
the TLV in octets. The value of this field MUST be 1, as there is
no Capability-specific data [[RFC5561]] following the TLV.
S-bit: Set to 1 to announce and 0 to withdraw the capability (as
per [RFC5561].
An mLDP speaker that has successfully advertised and negotiated "MT
Multipoint" capability MUST support the following:
1. Topology-scoped mLDP FECs in LDP messages (Section 4.1)
2. Topology-scoped mLDP forwarding setup (Section 7)
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6. MT Applicability on FEC-based features
6.1. Typed Wildcard MP FEC Elements
[RFC5918] extends base LDP and defines Typed Wildcard FEC Element
framework. Typed Wildcard FEC element can be used in any LDP message
to specify a wildcard operation for a given type of FEC.
The MT extensions, defined in this document, do not require any
extension to procedures for Typed Wildcard FEC Element support
[RFC5918], and these procedures apply as-is to Multipoint MT FEC
wildcarding. Similar to Typed Wildcard MT Prefix FEC Element, as
defined in [RFC7307], the MT extensions allow the use of "MT IP" or
"MT IPv6" in the Address Family field of the Typed Wildcard MP FEC
element. This is done in order to use wildcard operations for MP
FECs in the context of a given (sub)-topology as identified by the
MT-ID and IPA field.
This document defines the following format and encoding for a Typed
Wildcard MP FEC element:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Typed Wcard (5)| Type = MP FEC | Len = 6 | AF = MT IP ..|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|... or MT IPv6 | Reserved | IPA | MT-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|MT ID (contd.) |
+-+-+-+-+-+-+-+-+
Figure 5: Typed Wildcard MT MP FEC Element
Where:
Type: One of MP FEC Element type (P2MP, MP2MPup, MP2MP-down).
MT ID: MPLS MT ID
IPA: The IGP Algorithm
The defined format allows an LSR to perform wildcard MP FEC
operations under the scope of a (sub-)topology.
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6.2. End-of-LIB
[RFC5919] specifies extensions and procedures that allow an LDP
speaker to signal its End-of-LIB for a given FEC type to a peer. By
leveraging the End-of-LIB message, LDP ensures that label
distribution remains consistent and reliable, even during network
disruptions or maintenance activities. The MT extensions for MP FEC
do not require any modifications to these procedures and apply as-is
to MT MP FEC elements. Consequently, an MT mLDP speaker MAY signal
its convergence per (sub-)topology using the MT Typed Wildcard MP FEC
element.
7. Topology-Scoped Signaling and Forwarding
Since the {MT-ID, IPA} tuple is part of an mLDP FEC, there is no need
to support the concept of multiple (sub-)topology forwarding tables
in mLDP. Each MP LSP will be unique due to the tuple being part of
the FEC. There is also no need to have specific label forwarding
tables per topology, and each MP LSP will have its own unique local
label in the table. However, In order to implement MTR in an mLDP
network, the selection procedures for upstream LSR and downstream
forwarding interface need to be changed.
7.1. Upstream LSR selection
The procedures as described in RFC-6388 section-2.4.1.1 depend on the
best path to reach the root. When the {MT-ID, IPA} tuple is signaled
as part of the FEC, this tuple is used to select the (sub-)topology
that must be used to find the best path to the root address. Using
the next-hop from this best path, a LDP peer is selected following
the procedures as defined in [RFC6388].
7.2. Downstream forwarding interface selection
The procedures as described in RFC-6388 section-2.4.1.2 describe how
a downstream forwarding interface is selected. In these procedures,
any interface leading to the downstream LDP neighbor can be
considered as candidate forwarding interface. When the {MT-ID, IPA}
tuple is part of the FEC, this is no longer true. An interface must
only be selected if it is part of the same (sub-)topology that was
signaled in the mLDP FEC element. Besides this restriction, the
other procedures in [RFC6388] apply.
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8. LSP Ping Extensions
[RFC6425] defines procedures to detect data plane failures in
Multipoint MPLS LSPs. Section 3.1.2 of [RFC6425] defines new Sub-
Types and Sub-TLVs for Multipoint LDP FECs to be sent in "Target FEC
Stack" TLV of an MPLS echo request message [RFC8029].
To support LSP ping for MT Multipoint LSPs, this document uses
existing sub-types "P2MP LDP FEC Stack" and "MP2MP LDP FEC Stack"
defined in [RFC6425]. The LSP Ping extension is to specify "MT IP"
or "MT IPv6" in the "Address Family" field, set the "Address Length"
field to 8 (for MT IP) or 20 (for MT IPv6), and encode the sub-TLV
with additional {MT-ID, IPA} information as an extension to the "Root
LSR Address" field. The resultant format of sub-tlv is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Address Family (MT IP/MT IPv6) | Address Length| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
~ Root LSR Address (Cont.) ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | IPA | MT-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Opaque Length | Opaque Value ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
~ ~
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: Multipoint LDP FEC Stack Sub-TLV Format for MT
The rules and procedures of using this new sub-TLV in an MPLS echo
request message are the same as defined for P2MP/MP2MP LDP FEC Stack
Sub-TLV in [RFC6425]. The only difference is that the Root LSR
address is now (sub-)topology scoped.
9. Implementation Status
[Note to the RFC Editor - remove this section before publication, as
well as remove the reference to [RFC7942]
This section records the status of known implementations of the
protocol defined by this specification at the time of posting of this
Internet-Draft, and is based on a proposal described in [RFC7942] .
The description of implementations in this section is intended to
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assist the IETF in its decision processes in progressing drafts to
RFCs. Please note that the listing of any individual implementation
here does not imply endorsement by the IETF. Furthermore, no effort
has been spent to verify the information presented here that was
supplied by IETF contributors. This is not intended as, and must not
be construed to be, a catalog of available implementations or their
features. Readers are advised to note that other implementations may
exist.
According to [RFC7942] , "this will allow reviewers and working
groups to assign due consideration to documents that have the benefit
of running code, which may serve as evidence of valuable
experimentation and feedback that have made the implemented protocols
more mature. It is up to the individual working groups to use this
information as they see fit".
9.1. Cisco Systems
The feature has been implemented on IOS-XR.
* Organization: Cisco Systems
* Implementation: Cisco systems IOS-XR has an implementation.
Capability has been used from [RFC7307] and plan to update the
value once IANA assigns new value.
* Description: The implementation has been done.
* Maturity Level: Product
* Contact: mankamis@cisco.com
10. Security Considerations
This extension to mLDP does not introduce any new security
considerations beyond that already applied to the base LDP
specification [RFC5036], LDP extensions for Multi-Topology
specification [RFC7307] base mLDP specification [RFC6388], and MPLS
security framework [RFC5920].
11. IANA Considerations
This document defines a new LDP capability parameter TLV. IANA is
requested to assign the lowest available value after 0x0500 from "TLV
Type Name Space" in the "Label Distribution Protocol (LDP)
Parameters" registry within "Label Distribution Protocol (LDP) Name
Spaces" as the new code point for the LDP TLV code point.
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+-----+------------------+---------------+-------------------------+
|Value| Description | Reference | Notes/Registration Date |
+-----+------------------+---------------+-------------------------+
| TBA | MT Multipoint | This document | |
| | Capability | | |
+-----+------------------+---------------+-------------------------+
Figure 7: IANA Code Point
12. Contributor
Anuj Budhiraja Cisco systems
13. Acknowledgments
The authors would like to acknowledge Eric Rosen for his input on
this specification.
14. References
14.1. Normative References
[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/info/rfc2119>.
[RFC4915] Psenak, P., Mirtorabi, S., Roy, A., Nguyen, L., and P.
Pillay-Esnault, "Multi-Topology (MT) Routing in OSPF",
RFC 4915, DOI 10.17487/RFC4915, June 2007,
<https://www.rfc-editor.org/info/rfc4915>.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008,
<https://www.rfc-editor.org/info/rfc5120>.
[RFC6388] Wijnands, IJ., Ed., Minei, I., Ed., Kompella, K., and B.
Thomas, "Label Distribution Protocol Extensions for Point-
to-Multipoint and Multipoint-to-Multipoint Label Switched
Paths", RFC 6388, DOI 10.17487/RFC6388, November 2011,
<https://www.rfc-editor.org/info/rfc6388>.
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[RFC6425] Saxena, S., Ed., Swallow, G., Ali, Z., Farrel, A.,
Yasukawa, S., and T. Nadeau, "Detecting Data-Plane
Failures in Point-to-Multipoint MPLS - Extensions to LSP
Ping", RFC 6425, DOI 10.17487/RFC6425, November 2011,
<https://www.rfc-editor.org/info/rfc6425>.
[RFC6513] Rosen, E., Ed. and R. Aggarwal, Ed., "Multicast in MPLS/
BGP IP VPNs", RFC 6513, DOI 10.17487/RFC6513, February
2012, <https://www.rfc-editor.org/info/rfc6513>.
[RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
Encodings and Procedures for Multicast in MPLS/BGP IP
VPNs", RFC 6514, DOI 10.17487/RFC6514, February 2012,
<https://www.rfc-editor.org/info/rfc6514>.
[RFC7307] Zhao, Q., Raza, K., Zhou, C., Fang, L., Li, L., and D.
King, "LDP Extensions for Multi-Topology", RFC 7307,
DOI 10.17487/RFC7307, July 2014,
<https://www.rfc-editor.org/info/rfc7307>.
[RFC7942] Sheffer, Y. and A. Farrel, "Improving Awareness of Running
Code: The Implementation Status Section", BCP 205,
RFC 7942, DOI 10.17487/RFC7942, July 2016,
<https://www.rfc-editor.org/info/rfc7942>.
[RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N.,
Aldrin, S., and M. Chen, "Detecting Multiprotocol Label
Switched (MPLS) Data-Plane Failures", RFC 8029,
DOI 10.17487/RFC8029, March 2017,
<https://www.rfc-editor.org/info/rfc8029>.
[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/info/rfc8174>.
[RFC9350] Psenak, P., Ed., Hegde, S., Filsfils, C., Talaulikar, K.,
and A. Gulko, "IGP Flexible Algorithm", RFC 9350,
DOI 10.17487/RFC9350, February 2023,
<https://www.rfc-editor.org/info/rfc9350>.
14.2. Informative References
[IANA-IGP-ALGO-TYPES]
"IGP Algorithm Types", <https://www.iana.org/assignments/
igp-parameters/igp-parameters.xhtml#igp-algorithm-types>.
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[RFC5036] Andersson, L., Ed., Minei, I., Ed., and B. Thomas, Ed.,
"LDP Specification", RFC 5036, DOI 10.17487/RFC5036,
October 2007, <https://www.rfc-editor.org/info/rfc5036>.
[RFC5561] Thomas, B., Raza, K., Aggarwal, S., Aggarwal, R., and JL.
Le Roux, "LDP Capabilities", RFC 5561,
DOI 10.17487/RFC5561, July 2009,
<https://www.rfc-editor.org/info/rfc5561>.
[RFC5918] Asati, R., Minei, I., and B. Thomas, "Label Distribution
Protocol (LDP) 'Typed Wildcard' Forward Equivalence Class
(FEC)", RFC 5918, DOI 10.17487/RFC5918, August 2010,
<https://www.rfc-editor.org/info/rfc5918>.
[RFC5919] Asati, R., Mohapatra, P., Chen, E., and B. Thomas,
"Signaling LDP Label Advertisement Completion", RFC 5919,
DOI 10.17487/RFC5919, August 2010,
<https://www.rfc-editor.org/info/rfc5919>.
[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010,
<https://www.rfc-editor.org/info/rfc5920>.
Authors' Addresses
IJsbrand Wijnands
Individual
Email: ice@braindump.be
Mankamana Mishra
Cisco Systems, Inc.
821 Alder Drive
Milpitas, CA 95035
United States of America
Email: mankamis@cisco.com
Kamran Raza
Cisco Systems, Inc.
2000 Innovation Drive
Kanata ON K2K-3E8
Canada
Email: skraza@cisco.com
Wijnands, et al. Expires 21 November 2024 [Page 15]
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Zhaohui Zhang
Juniper Networks
10 Technology Park Dr.
Westford, MA 01886
United States of America
Email: zzhang@juniper.net
Arkadiy Gulko
Edward Jones wealth management
United States of America
Email: Arkadiy.gulko@edwardjones.com
Wijnands, et al. Expires 21 November 2024 [Page 16]