Internet DRAFT - draft-ietf-mpls-mldp-multi-topology
draft-ietf-mpls-mldp-multi-topology
MPLS Working Group IJ. Wijnands
Internet-Draft Individual
Intended status: Standards Track M. Mishra (Editor)
Expires: 2 February 2024 K. Raza
A. Budhiraja
Cisco Systems, Inc.
Z. Zhang
Juniper Networks
A. Gulko
Edward Jones wealth management
1 August 2023
mLDP Extensions for Multi-Topology Routing
draft-ietf-mpls-mldp-multi-topology-03
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 and/or FA, mLDP is required to become topology and
FA aware. This document specifies extensions to mLDP to support MTR
with FA such that when building a Multipoint LSPs(Label Switched
Paths) it can follow a particular topology and algorithm.
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 2 February 2024.
Wijnands, et al. Expires 2 February 2024 [Page 1]
Internet-Draft Multi-Topology mLDP August 2023
Copyright Notice
Copyright (c) 2023 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 . . . . . . . . . . . . . . . . 4
4.1.1. MP FEC Element . . . . . . . . . . . . . . . . . . . 5
4.1.2. MT IP Address Families . . . . . . . . . . . . . . . 5
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 . . . . . . . . . . . . . . . . . . . . . 10
9. Implementation Status . . . . . . . . . . . . . . . . . . . . 11
9.1. Cisco Systems . . . . . . . . . . . . . . . . . . . . . . 12
10. Security Considerations . . . . . . . . . . . . . . . . . . . 12
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
13.1. Normative References . . . . . . . . . . . . . . . . . . 13
13.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Glossary
MT - Multi-Topology
MT-ID - Multi-Topology Identifier
Wijnands, et al. Expires 2 February 2024 [Page 2]
Internet-Draft Multi-Topology mLDP August 2023
MTR - Multi-Topology Routing
IGP - Interior Gateway Protocol
MP - Multipoint (P2MP or MP2MP)
LDP - Label Distribution Protocol
mLDP - Multipoint LDP
P2MP - Point-to-Multipoint
MP2MP - Multipoint-to-Multipoint
FEC - Forwarding Equivalence Class
LSP - Label Switched Path
FA - Flexible Algorithm
IPA - IGP Algorithm
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 ISIS 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 light weight mechanism to define constraint-based topologies
is Flexible Algorithm (FA) [RFC9350]. FA can be seen as creating a
sub-topology within a topology using defined topology constraints and
computation algorithm. This can be done within a MTR topology or
just the default Topology. An instance of such a sub-topology is
identified by a 1 octet value as documented in [RFC9350]). Flexible
Algorithm is a mechanism to create a sub-topology, but in the future
different algorithms might be defined on how to achieve that. For
that reason, in the remainder of this document we'll refer to this as
the IGP Algorithm (IPA).
Wijnands, et al. Expires 2 February 2024 [Page 3]
Internet-Draft Multi-Topology mLDP August 2023
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 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/IPA such
that when building a Multi-Point LSPs it can follow a particular
topology and alogirthm. This means that the identifier for the
particular Topology to be used by mLDP have to become a two tuple
(MTR Topology Id, IGP Algorithm).
3. Specification of Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
In this document, these words will appear with that interpretation
only when in ALL CAPS. Lower case uses of these words are not to be
interpreted as carrying RFC-2119 significance.
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.
The same applies to the IPA. The IPA needs to be encoded as part of
the mLDP FEC to create unique MP-LSPs and at the same time is used to
signal to mLDP (hop-by-hop) which Algorithm needs to be used to
create the MP-LSP.
Since the MT-ID and IPA 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
Following subsections propose the extensions to bind an mLDP FEC to a
topology. The mLDP MT extensions reuse some of the extensions
specified in [RFC7307].
Wijnands, et al. Expires 2 February 2024 [Page 4]
Internet-Draft Multi-Topology mLDP August 2023
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 "Root Node Address" encoding is as defined for given "Address
Family", and whose length (in octets) is specified by the "AF Length"
field.
To extend MP FEC elements for MT, the {MT-ID, IPA} is a tuple that is
relevant in the context of the root address of the MP LSP. The {MT-
ID, IPA} tuple determines in which (sub)-topology the root address
needs to be resolved. Since the {MT-ID, IPA} tuple should be
considered part of the mLDP FEC, the most natural place to encode
this tuple is as part of the root address. While encoding it, we
also propose to use "MT IP" Address Families as described in
following sub section.
4.1.2. MT IP Address Families
[RFC7307] has specified new address families, named "MT IP" and "MT
IPv6", to allow specification of an IP prefix within a topology
scope. In addition to using this address family for mLDP, we also
use 8 bits of the 16 bits Reserved field to encode the IGP Algorithm
(IPA) Registry. The resulting format of the data associated with
these new Address Families is as follows:
Wijnands, et al. Expires 2 February 2024 [Page 5]
Internet-Draft Multi-Topology mLDP August 2023
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, values are from the IGP Algorithm
registry.
Reserved: This 8-bit field MUST be zero on transmission and
ignored on receipt.
4.1.3. MT MP FEC Element
By using extended MT IP Address Family, the resultant MT MP FEC
element is to be encoded as follows:
Wijnands, et al. Expires 2 February 2024 [Page 6]
Internet-Draft Multi-Topology mLDP August 2023
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
include:
* MP FEC Elements:
- P2MP (type 0x6)
- MP2MP-up (type 0x7)
- MP2MP-down (type 0x8)
* Typed Wildcard FEC Element (type 0x5)
In case of "Typed Wildcard FEC Element", the sub 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. When the
Tunnel Type is set to mLDP P2MP LSP, the Tunnel Identifier is a P2MP
FEC Element. When the Tunnel Type is set to mLDP Multipoint-to-
Multipoint (MP2MP) LSP, the Tunnel Identifier is an MP2MP FEC
Element. For deploying mLDP in a network that supports MTR and FA,
New MT MP FEC element SHOULD be used as the Tunnel identifier.
4.2. Topology IDs
This document assumes the same definitions and procedures associated
with MPLS MT-ID as defined in [RFC7307] specification.
Wijnands, et al. Expires 2 February 2024 [Page 7]
Internet-Draft Multi-Topology mLDP August 2023
5. MT Multipoint Capability
"MT Multipoint Capability" is a new LDP capability, defined in
accordance with LDP Capability definition guidelines [RFC5561], that
is to be advertised to its peers by an mLDP speaker to announce its
capability to support MTR and the procedures specified in this
document. This capability MAY be sent either in an Initialization
message at the session establishment time, or in a Capability message
dynamically during the lifetime of a session (only if "Dynamic
Announcement" capability [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 Cap.(IANA) | 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 Capaility: TLV type (IANA assigned).
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.
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)
Wijnands, et al. Expires 2 February 2024 [Page 8]
Internet-Draft Multi-Topology mLDP August 2023
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 proposed in document do not require any extension
in procedures for Typed Wildcard FEC Element support [RFC5918], and
these procedures apply as-is to Multipoint MT FEC wildcarding. Like
Typed Wildcard MT Prefix FEC Element, as defined in [RFC7307], the MT
extensions allow use of "MT IP" or "MT IPv6" in the Address Family
field of the Typed Wildcard MP FEC element 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 proposes 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, values are from the IGP Algorithm
registry.
The proposed format allows an LSR to perform wildcard MP FEC
operations under the scope of a (sub-)topology.
Wijnands, et al. Expires 2 February 2024 [Page 9]
Internet-Draft Multi-Topology mLDP August 2023
6.2. End-of-LIB
[RFC5919] specifies extensions and procedures that allows an LDP
speaker to signal its End-of-LIB (i.e. convergence) for a given FEC
type towards a peer. MT extensions for MP FEC do not require any
change in these procedures and they apply as-is to MT MP FEC
elements. This means that an MT mLDP speaker MAY signal its
convergence per (sub-)topology using 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.
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].
Wijnands, et al. Expires 2 February 2024 [Page 10]
Internet-Draft Multi-Topology mLDP August 2023
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 proposed 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 same as defined for P2MP/MP2MP LDP FEC Stack Sub-
TLV in [RFC6425] with only difference being that 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]
Wijnands, et al. Expires 2 February 2024 [Page 11]
Internet-Draft Multi-Topology mLDP August 2023
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
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
* 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 apply to the base LDP
specification [RFC5036], 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.
Wijnands, et al. Expires 2 February 2024 [Page 12]
Internet-Draft Multi-Topology mLDP August 2023
+-----+------------------+---------------+-------------------------+
|Value| Description | Reference | Notes/Registration Date |
+-----+------------------+---------------+-------------------------+
| TBA | MT Multipoint | This document | |
| | Capability | | |
+-----+------------------+---------------+-------------------------+
Figure 7: IANA Code Point
12. Acknowledgments
The authors would like to acknowledge Eric Rosen for his input on
this specification.
13. References
13.1. 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>.
[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>.
Wijnands, et al. Expires 2 February 2024 [Page 13]
Internet-Draft Multi-Topology mLDP August 2023
[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>.
[RFC9350] Psenak, P., Ed., Hegde, S., Filsfils, C., Talaulikar, K.,
and A. Gulko, "IGP Flexible Algorithm", RFC 9350,
DOI 10.17487/RFC9350, February 2023, <httpss://www.rfc-
editor.org/info/rfc9350>.
13.2. Informative References
[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>.
Wijnands, et al. Expires 2 February 2024 [Page 14]
Internet-Draft Multi-Topology mLDP August 2023
[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
Anuj Budhiraja
Cisco Systems, Inc.
821 Alder Drive
Milpitas, CA 95035
United States of America
Email: abudhira@cisco.com
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 2 February 2024 [Page 15]
