rfc9084.original   rfc9084.txt 
LSR Working Group A. Wang Internet Engineering Task Force (IETF) A. Wang
Internet-Draft China Telecom Request for Comments: 9084 China Telecom
Intended status: Standards Track A. Lindem Category: Standards Track A. Lindem
Expires: October 11, 2021 Cisco Systems ISSN: 2070-1721 Cisco Systems, Inc.
J. Dong J. Dong
Huawei Technologies Huawei Technologies
P. Psenak P. Psenak
K. Talaulikar, Ed. K. Talaulikar, Ed.
Cisco Systems Cisco Systems, Inc.
April 9, 2021 August 2021
OSPF Prefix Originator Extensions OSPF Prefix Originator Extensions
draft-ietf-lsr-ospf-prefix-originator-12
Abstract Abstract
This document defines OSPF extensions to include information This document defines OSPF extensions to include information
associated with the node originating a prefix along with the prefix associated with the node originating a prefix along with the prefix
advertisement. These extensions do not change the core OSPF route advertisement. These extensions do not change the core OSPF route
computation functionality but provide useful information for network computation functionality but provide useful information for network
analysis, troubleshooting, and use-cases like traffic engineering. analysis, troubleshooting, and use cases like traffic engineering.
Status of This Memo Status of This Memo
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provisions of BCP 78 and BCP 79.
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Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on October 11, 2021. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9084.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language
2. Protocol Extensions . . . . . . . . . . . . . . . . . . . . . 3 2. Protocol Extensions
2.1. Prefix Source OSPF Router-ID Sub-TLV . . . . . . . . . . 4 2.1. Prefix Source OSPF Router-ID Sub-TLV
2.2. Prefix Source Router Address Sub-TLV . . . . . . . . . . 5 2.2. Prefix Source Router Address Sub-TLV
3. Elements of Procedure . . . . . . . . . . . . . . . . . . . . 5 3. Elements of Procedure
4. Security Considerations . . . . . . . . . . . . . . . . . . . 6 4. Security Considerations
5. Operational Considerations . . . . . . . . . . . . . . . . . 7 5. Operational Considerations
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations
7. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 8 7. References
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 7.1. Normative References
8.1. Normative References . . . . . . . . . . . . . . . . . . 8 7.2. Informative References
8.2. Informative References . . . . . . . . . . . . . . . . . 9 Acknowledgement
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 Authors' Addresses
1. Introduction 1. Introduction
Prefix attributes are advertised in OSPFv2 [RFC2328] using the Prefix attributes are advertised in OSPFv2 [RFC2328] using the
Extended Prefix Opaque Link State Advertisement (LSA) [RFC7684] and Extended Prefix Opaque Link State Advertisement (LSA) [RFC7684] and
in OSPFv3 [RFC5340] using the various Extended Prefix LSA types in OSPFv3 [RFC5340] using the various Extended Prefix LSA types
[RFC8362]. [RFC8362].
The procedures for identification of the originating router for a The procedures for identification of the originating router for a
prefix in OSPF vary by the type of the prefix and, currently, it is prefix in OSPF vary by the type of the prefix and, currently, it is
not always possible to produce an accurate result. For intra-area not always possible to produce an accurate result. For intra-area
prefixes, the originating router is identified by the Advertising prefixes, the originating router is identified by the Advertising
Router field of the area-scoped LSA used for those prefix Router field of the area-scoped LSA used for those prefix
advertisements. However, for the inter-area prefixes advertised by advertisements. However, for inter-area prefixes advertised by an
the Area Border Router (ABR), the Advertising Router field of their Area Border Router (ABR), the Advertising Router field of their area-
area-scoped LSAs is set to the ABR itself and the information about scoped LSAs is set to the ABR itself and the information about the
the router originating the prefix advertisement is lost in this router originating the prefix advertisement is lost in the process of
process of prefix propagation across areas. For Autonomous System prefix propagation across areas. For Autonomous System (AS) external
(AS) external prefixes, the originating router may be considered as prefixes, the originating router may be considered as the Autonomous
the Autonomous System Border Router (ASBR) and is identified by the System Border Router (ASBR) and is identified by the Advertising
Advertising Router field of the AS-scoped LSA used. However, the Router field of the AS-scoped LSA used. However, the actual
actual originating router for the prefix may be a remote router originating router for the prefix may be a remote router outside the
outside the OSPF domain. Similarly, when an ABR performs translation OSPF domain. Similarly, when an ABR performs translation of Not-So-
of Not-So-Stubby Area (NSSA) [RFC3101] LSAs to AS-external LSAs, the Stubby Area (NSSA) [RFC3101] LSAs to AS-external LSAs, the
information associated with the NSSA ASBR (or the router outside the information associated with the NSSA ASBR (or the router outside the
OSPF domain) is not conveyed across the OSPF domain. OSPF domain) is not propagated across the OSPF domain.
While typically the originator of information in OSPF is identified While typically the originator of information in OSPF is identified
by its OSPF Router ID, it does not necessarily represent a reachable by its OSPF Router ID, it does not necessarily represent a reachable
address for the router since the OSPF Router ID is a 32-bit number. address for the router since the OSPF Router ID is a 32-bit number
There exists a prevalent practice to use one of the IPv4 address of that is unique in the OSPF domain. For OSPFv2, a common practice is
the node (e.g. a loopback interface) as an OSPF Router ID in the case to use one of the IPv4 addresses of the node (e.g., a loopback
of OSPFv2. However, this cannot be always assumed and this approach interface) as the OSPF Router ID. However, this cannot always be
does not extend to IPv6 addresses with OSPFv3. The IPv4/IPv6 Router assumed and this approach does not apply to IPv6 addresses with
Address as defined in [RFC3630] and [RFC5329] for OSPFv2 and OSPFv3 OSPFv3. The IPv4/IPv6 Router Address, as respectively defined in
respectively provide an address to reach that router. [RFC3630] and [RFC5329] for OSPFv2 and OSPFv3, provides an address to
reach the advertising router.
The primary use case for the extensions proposed in this document is The primary use case for the extensions proposed in this document is
to be able to identify the originator of a prefix in the network. In to be able to identify the originator of a prefix in the network. In
cases where multiple prefixes are advertised by a given router, it is cases where multiple prefixes are advertised by a given router, it is
also useful to be able to associate all these prefixes with a single also useful to be able to associate all these prefixes with a single
router even when prefixes are advertised outside of the area in which router even when prefixes are advertised outside of the area in which
they originated. It also helps to determine when the same prefix is they originated. It also helps to determine when the same prefix is
being originated by multiple routers across areas. being originated by multiple routers across areas.
This document proposes extensions to the OSPF protocol for the This document proposes extensions to the OSPF protocol for the
inclusion of information associated with the router originating the inclusion of information associated with the router originating the
prefix along with the prefix advertisement. These extensions do not prefix along with the prefix advertisement. These extensions do not
change the core OSPF route computation functionality. They provide change the core OSPF route computation functionality. They provide
useful information for topology analysis and traffic engineering, useful information for topology analysis and traffic engineering,
especially on a controller when this information is advertised as an especially on a controller when this information is advertised as an
attribute of the prefixes via mechanisms such as Border Gateway attribute of the prefixes via mechanisms such as Border Gateway
Protocol Link-State (BGP-LS) [RFC7752] Protocol - Link State (BGP-LS) [RFC7752] [RFC9085].
[I-D.ietf-idr-bgp-ls-segment-routing-ext].
1.1. Requirements Language 1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in
14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
2. Protocol Extensions 2. Protocol Extensions
This document defines the Prefix Source OSPF Router-ID and the Prefix This document defines the Prefix Source OSPF Router-ID and the Prefix
Source Router Address Sub-TLVs. They are used, respectively, to Source Router Address Sub-TLVs. They are used, respectively, to
include the Router ID of, and a reachable address of, the router that include the Router ID of, and a reachable address of, the router that
originates the prefix as a prefix attribute. originates the prefix as a prefix attribute.
2.1. Prefix Source OSPF Router-ID Sub-TLV 2.1. Prefix Source OSPF Router-ID Sub-TLV
For OSPFv2, the Prefix Source OSPF Router-ID Sub-TLV is an optional For OSPFv2, the Prefix Source OSPF Router-ID Sub-TLV is an optional
Sub-TLV of the OSPFv2 Extended Prefix TLV [RFC7684]. For OSPFv3, the sub-TLV of the OSPFv2 Extended Prefix TLV [RFC7684]. For OSPFv3, the
Prefix Source OSPF Router-ID Sub-TLV is an optional Sub-TLV of the Prefix Source OSPF Router-ID Sub-TLV is an optional sub-TLV of the
Intra-Area-Prefix TLV, Inter-Area-Prefix TLV, and External-Prefix TLV Intra-Area-Prefix TLV, Inter-Area-Prefix TLV, and External-Prefix TLV
[RFC8362] when originating either an IPv4 [RFC5838] or an IPv6 prefix [RFC8362] when originating either an IPv4 [RFC5838] or an IPv6 prefix
advertisement. advertisement.
The Prefix Source OSPF Router-ID Sub-TLV has the following format: The Prefix Source OSPF Router-ID Sub-TLV has the following format:
0 1 2 3 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 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 | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OSPF Router ID | | OSPF Router ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Prefix Source OSPF Router-ID Sub-TLV Format Figure 1: Prefix Source OSPF Router-ID Sub-TLV Format
Where:
o Type: 4 for OSPFv2 and 27 for OSPFv3 Where:
Type: 4 for OSPFv2 and 27 for OSPFv3
o Length: 4 Length: 4
o OSPF Router ID : the OSPF Router ID of the OSPF router that OSPF Router ID: the OSPF Router ID of the OSPF router that
originated the prefix advertisement in the OSPF domain. originated the prefix advertisement in the OSPF domain
The parent TLV of a prefix advertisement MAY include more than one The parent TLV of a prefix advertisement MAY include more than one
Prefix Source OSPF Router-ID sub-TLV, one corresponding to each of Prefix Source OSPF Router-ID Sub-TLV, one corresponding to each of
the Equal-Cost Multi-Path (ECMP) nodes that originated the given the Equal-Cost Multipath (ECMP) nodes that originated the advertised
prefix. prefix.
For intra-area prefix advertisements, the Prefix Source OSPF Router- For intra-area prefix advertisements, the Prefix Source OSPF Router-
ID Sub-TLV MUST be considered invalid and ignored if the OSPF Router ID Sub-TLV MUST be considered invalid and ignored if the OSPF Router
ID field is not the same as the Advertising Router field in the ID field is not the same as the Advertising Router field in the
containing LSA. Similar validation cannot be reliably performed for containing LSA. Similar validation cannot be reliably performed for
inter-area and external prefix advertisements. inter-area and external prefix advertisements.
A received Prefix Source OSPF Router-ID Sub-TLV with OSPF Router ID A received Prefix Source OSPF Router-ID Sub-TLV with the OSPF Router
set to 0 MUST be considered invalid and ignored. Additionally, ID field set to 0 MUST be considered invalid and ignored.
reception of such Sub-TLV SHOULD be logged as an error (subject to Additionally, reception of such sub-TLVs SHOULD be logged as an error
rate-limiting). (subject to rate limiting).
2.2. Prefix Source Router Address Sub-TLV 2.2. Prefix Source Router Address Sub-TLV
For OSPFv2, the Prefix Source Router Address Sub-TLV is an optional For OSPFv2, the Prefix Source Router Address Sub-TLV is an optional
Sub-TLV of the OSPFv2 Extended Prefix TLV [RFC7684]. For OSPFv3, the sub-TLV of the OSPFv2 Extended Prefix TLV [RFC7684]. For OSPFv3, the
Prefix Source Router Address Sub-TLV is an optional Sub-TLV of the Prefix Source Router Address Sub-TLV is an optional sub-TLV of the
Intra-Area-Prefix TLV, Inter-Area-Prefix TLV, and External-Prefix TLV Intra-Area-Prefix TLV, Inter-Area-Prefix TLV, and External-Prefix TLV
[RFC8362] when originating either an IPv4 [RFC5838] or an IPv6 prefix [RFC8362] when originating either an IPv4 [RFC5838] or an IPv6 prefix
advertisement. advertisement.
The Prefix Source Router Address Sub-TLV has the following format: The Prefix Source Router Address Sub-TLV has the following format:
0 1 2 3 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 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 | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Router Address (4 or 16 octets) | | Router Address (4 or 16 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Prefix Source Router Address Sub-TLV Format Figure 2: Prefix Source Router Address Sub-TLV Format
Where:
o Type: 5 (suggested) for OSPFv2 and 28 (suggested) for OSPFv3 Where:
Type: 5 for OSPFv2 and 28 for OSPFv3
o Length: 4 or 16 Length: 4 or 16
o Router Address: A reachable IPv4 or IPv6 router address for the Router Address: A reachable IPv4 or IPv6 router address for the
router that originated the IPv4 or IPv6 prefix advertisement router that originated the IPv4 or IPv6 prefix advertisement,
respectively. Such an address would be semantically equivalent to respectively. Such an address would be semantically equivalent
what may be advertised in the OSPFv2 Router Address TLV [RFC3630] to what may be advertised in the OSPFv2 Router Address TLV
or in the OSPFv3 Router IPv6 Address TLV [RFC5329]. [RFC3630] or in the OSPFv3 Router IPv6 Address TLV [RFC5329].
The parent TLV of a prefix advertisement MAY include more than one The parent TLV of a prefix advertisement MAY include more than one
Prefix Source Router Address Sub-TLV, one corresponding to each of Prefix Source Router Address Sub-TLV, one corresponding to each of
the Equal-Cost Multi-Path (ECMP) nodes that originated the given the Equal-Cost Multipath (ECMP) nodes that originated the advertised
prefix. prefix.
A received Prefix Source Router Address Sub-TLV that has an invalid A received Prefix Source Router Address Sub-TLV that has an invalid
length (i.e. not consistent with the prefix's address family) MUST be length (i.e., not consistent with the prefix's address family) MUST
considered invalid and ignored. Additionally, reception of such Sub- be considered invalid and ignored. Additionally, reception of such
TLV SHOULD be logged as an error (subject to rate-limiting). sub-TLVs SHOULD be logged as an error (subject to rate limiting).
3. Elements of Procedure 3. Elements of Procedure
This section describes the procedure for the advertisement of the This section describes the procedure for the advertisement of the
Prefix Source OSPF Router-ID and Prefix Source Router Address Sub- Prefix Source OSPF Router-ID and Prefix Source Router Address Sub-
TLVs along with the prefix advertisement. TLVs along with the prefix advertisement.
The OSPF Router ID of the Prefix Source OSPF Router-ID is set to the The OSPF Router ID of the Prefix Source OSPF Router-ID is set to the
OSPF Router ID of the node originating the prefix in the OSPF domain. OSPF Router ID of the node originating the prefix in the OSPF domain.
If the originating node is advertising an OSPFv2 Router Address TLV If the originating node is advertising an OSPFv2 Router Address TLV
[RFC3630] or an OSPFv3 Router IPv6 Address TLV [RFC5329], then the [RFC3630] or an OSPFv3 Router IPv6 Address TLV [RFC5329], then the
same address MUST be used in the Router Address field of the Prefix same address MUST be used in the Router Address field of the Prefix
Source Router Address Sub-TLV. When the originating node is not Source Router Address Sub-TLV. When the originating node is not
advertising such an address, implementations can determine a unique advertising such an address, implementations can select a unique and
and reachable address (for example, advertised with the N-flag set reachable local address (for example, advertised with the N-Flag set
[RFC7684] or N-bit set [RFC8362]) belonging to the originating node [RFC7684] or N-bit set [RFC8362]) on the originating node to
to set in the Router Address field. advertise in the Router Address field.
When an ABR generates inter-area prefix advertisements into its non- When an ABR generates inter-area prefix advertisements into its non-
backbone areas corresponding to an inter-area prefix advertisement backbone areas corresponding to an inter-area prefix advertisement
from the backbone area, the only way to determine the originating from the backbone area, the only way to determine the originating
node information is based on the Prefix Source OSPF Router-ID and node information is based on the Prefix Source OSPF Router-ID and
Prefix Source Router Address Sub-TLVs present in the inter-area Prefix Source Router Address Sub-TLVs present in the inter-area
prefix advertisement originated into the backbone area by an ABR from prefix advertisement originated into the backbone area by an ABR from
another non-backbone area. The ABR performs its prefix calculation another non-backbone area. The ABR performs its prefix calculation
to determine the set of nodes that contribute to the best prefix to determine the set of nodes that contribute to ECMP paths for the
reachability. It MUST use the prefix originator information only prefix. It MUST only use the prefix originator information from this
from this set of nodes. The ABR MUST NOT include the Prefix Source set of nodes. The ABR MUST NOT include the Prefix Source OSPF
OSPF Router-ID or the Prefix Source Router Address Sub-TLVs when it Router-ID or the Prefix Source Router Address Sub-TLVs when it is
is unable to determine the information of the best originating nodes. unable to determine the information for the originating nodes
contributing ECMP paths.
Implementations may support the propagation of the originating node Implementations may support the propagation of the originating node
information along with a redistributed prefix into the OSPF domain information along with a redistributed prefix into the OSPF domain
from another routing domain. The details of such mechanisms are from another routing domain. The details of such mechanisms are
outside the scope of this document. Such implementations may also outside the scope of this document. Such implementations may also
provide control on whether the Router Address in the Prefix Source provide control on whether the Router Address in the Prefix Source
Router Address Sub-TLV is set as the ABSR node address or as the Router Address Sub-TLV is set as the ASBR node address or as the
address of the actual node outside the OSPF domain that owns the address of the actual node outside the OSPF domain that owns the
prefix. prefix.
When translating the NSSA prefix advertisements [RFC3101] to the AS When translating NSSA prefix advertisements [RFC3101] to AS external
external prefix advertisements, the NSSA ABR, follows the same prefix advertisements, the NSSA ABR follows the same procedures as an
procedures as an ABR generating inter-area prefix advertisements for ABR generating inter-area prefix advertisements for the propagation
the propagation of the originating node information. of the originating node information.
4. Security Considerations 4. Security Considerations
Since this document extends the OSPFv2 Extended Prefix LSA, the Since this document extends the OSPFv2 Extended Prefix LSA, the
security considerations for [RFC7684] are applicable. Similarly, security considerations for [RFC7684] are applicable. Similarly,
since this document extends the OSPFv3 E-Intra-Area-Prefix-LSA, E- since this document extends the OSPFv3 E-Intra-Area-Prefix-LSA, E-
Inter-Area-Prefix-LSA, E-AS-External LSA, and E-NSSA-LSA, the Inter-Area-Prefix-LSA, E-AS-External-LSA, and E-NSSA-LSA, the
security considerations for [RFC8362] are applicable. The new sub- security considerations for [RFC8362] are applicable. The new sub-
TLVs introduced in this document are optional and do not affect the TLVs introduced in this document are optional and do not affect the
OSPF route computation and therefore do not affect the security OSPF route computation and therefore do not affect the security
aspects of OSPF protocol operations. aspects of OSPF protocol operations.
A rogue node that can inject prefix advertisements may use the new A rogue node that can inject prefix advertisements may use the
extensions introduced in this document to indicate an incorrect extensions introduced in this document to advertise bogus prefix
prefix source information. source information.
5. Operational Considerations 5. Operational Considerations
Consideration should be given to the operational impact of the Consideration should be given to the operational impact of the
increase in the size of the OSPF Link-State Database as a result of increase in the size of the OSPF Link-State Database as a result of
the protocol extensions in this document. Based on deployment design the protocol extensions in this document. Based on deployment design
and requirements, a subset of prefixes may be identified for which and requirements, a subset of prefixes may be identified for which
the originating node information needs to be included with their originating node information is required to be included in prefix
prefix advertisements. advertisements.
The propagation of the prefix source node information when doing The propagation of prefix source node information for prefix
prefix advertisements across OSPF area or domain boundaries results advertisements advertised across an OSPF area or domain boundaries
in the exposure of node information outside of an area or domain will expose information outside of an area or domain where it would
within which it is normally hidden or abstracted by the base OSPF normally be hidden or abstracted by the base OSPF protocol. Based on
protocol. Based on deployment design and requirements, a subset of deployment design and requirements, the propagation of node
prefixes may be identified for which the propagation of the information across area or domain boundaries may be limited to a
originating node information across area or domain boundaries is subset of prefixes in the ABRs or ASBRs, respectively.
disabled at the ABRs or ASBRs respectively.
The identification of the node that is originating a specific prefix The identification of the node that is originating a specific prefix
in the network may aid in debugging of issues related to prefix in the network may aid in the debugging of issues related to prefix
reachability within an OSPF network. reachability within an OSPF network.
6. IANA Considerations 6. IANA Considerations
This document requests IANA for the allocation of the codepoints from Per this document, IANA has allocated the following codepoints from
the "OSPFv2 Extended Prefix TLV Sub-TLVs" registry under the "Open the "OSPFv2 Extended Prefix TLV Sub-TLVs" registry under the "Open
Shortest Path First v2 (OSPFv2) Parameters" registry. Shortest Path First v2 (OSPFv2) Parameters" registry.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +=======+==============================+===========+
| Code | Description | IANA Allocation | | Value | Description | Reference |
| Point | | Status | +=======+==============================+===========+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 4 | Prefix Source OSPF Router-ID | RFC 9084 |
| 4 | Prefix Source OSPF Router-ID | early allocation done | +-------+------------------------------+-----------+
| 5 | Prefix Source Router Address | suggested | | 5 | Prefix Source Router Address | RFC 9084 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-------+------------------------------+-----------+
Figure 3: Codepoints in OSPFv2 Extended Prefix TLV Sub-TLVs Table 1: Codepoints in OSPFv2 Extended Prefix
TLV Sub-TLVs
This document requests IANA for the allocation of the codepoints from Per this document, IANA has allocated the following codepoints from
the "OSPFv3 Extended-LSA Sub-TLVs" registry under the "Open Shortest the "OSPFv3 Extended-LSA Sub-TLVs" registry under the "Open Shortest
Path First v3 (OSPFv3) Parameters" registry. Path First v3 (OSPFv3) Parameters" registry.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +=======+==============================+===========+
| Code | Description | IANA Allocation | | Value | Description | Reference |
| Point | | Status | +=======+==============================+===========+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 27 | Prefix Source OSPF Router-ID | RFC 9084 |
| 27 | Prefix Source OSPF Router-ID | early allocation done | +-------+------------------------------+-----------+
| 28 | Prefix Source Router Address | suggested | | 28 | Prefix Source Router Address | RFC 9084 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-------+------------------------------+-----------+
Figure 4: Codepoints in OSPFv3 Extended-LSA Sub-TLVs
7. Acknowledgement
Many thanks to Les Ginsberg for his suggestions on this draft. Also Table 2: Codepoints in OSPFv3 Extended-LSA Sub-TLVs
thanks to Jeff Tantsura, Rob Shakir, Gunter Van De Velde, Goethals
Dirk, Smita Selot, Shaofu Peng, John E Drake and Baalajee S for their
review and valuable comments. The authors would also like to thank
Alvaro Retana for his detailed review and suggestions for the
improvement of this document.
8. References 7. References
8.1. Normative References 7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998, DOI 10.17487/RFC2328, April 1998,
<https://www.rfc-editor.org/info/rfc2328>. <https://www.rfc-editor.org/info/rfc2328>.
skipping to change at page 9, line 23 skipping to change at line 379
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8362] Lindem, A., Roy, A., Goethals, D., Reddy Vallem, V., and [RFC8362] Lindem, A., Roy, A., Goethals, D., Reddy Vallem, V., and
F. Baker, "OSPFv3 Link State Advertisement (LSA) F. Baker, "OSPFv3 Link State Advertisement (LSA)
Extensibility", RFC 8362, DOI 10.17487/RFC8362, April Extensibility", RFC 8362, DOI 10.17487/RFC8362, April
2018, <https://www.rfc-editor.org/info/rfc8362>. 2018, <https://www.rfc-editor.org/info/rfc8362>.
8.2. Informative References 7.2. Informative References
[I-D.ietf-idr-bgp-ls-segment-routing-ext]
Previdi, S., Talaulikar, K., Filsfils, C., Gredler, H.,
and M. Chen, "BGP Link-State extensions for Segment
Routing", draft-ietf-idr-bgp-ls-segment-routing-ext-16
(work in progress), June 2019.
[RFC3101] Murphy, P., "The OSPF Not-So-Stubby Area (NSSA) Option", [RFC3101] Murphy, P., "The OSPF Not-So-Stubby Area (NSSA) Option",
RFC 3101, DOI 10.17487/RFC3101, January 2003, RFC 3101, DOI 10.17487/RFC3101, January 2003,
<https://www.rfc-editor.org/info/rfc3101>. <https://www.rfc-editor.org/info/rfc3101>.
[RFC5838] Lindem, A., Ed., Mirtorabi, S., Roy, A., Barnes, M., and [RFC5838] Lindem, A., Ed., Mirtorabi, S., Roy, A., Barnes, M., and
R. Aggarwal, "Support of Address Families in OSPFv3", R. Aggarwal, "Support of Address Families in OSPFv3",
RFC 5838, DOI 10.17487/RFC5838, April 2010, RFC 5838, DOI 10.17487/RFC5838, April 2010,
<https://www.rfc-editor.org/info/rfc5838>. <https://www.rfc-editor.org/info/rfc5838>.
[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752, Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016, DOI 10.17487/RFC7752, March 2016,
<https://www.rfc-editor.org/info/rfc7752>. <https://www.rfc-editor.org/info/rfc7752>.
[RFC9085] Previdi, S., Talaulikar, K., Ed., Filsfils, C., Gredler,
H., and M. Chen, "Border Gateway Protocol - Link State
(BGP-LS) Extensions for Segment Routing", RFC 9085,
DOI 10.17487/RFC9085, August 2021,
<https://www.rfc-editor.org/info/rfc9085>.
Acknowledgement
Many thanks to Les Ginsberg for his suggestions on this document.
Also, thanks to Jeff Tantsura, Rob Shakir, Gunter Van de Velde,
Goethals Dirk, Smita Selot, Shaofu Peng, John E. Drake, and Baalajee
S. for their review and valuable comments. The authors would also
like to thank Alvaro Retana for his detailed review and suggestions
for the improvement of this document.
Authors' Addresses Authors' Addresses
Aijun Wang Aijun Wang
China Telecom China Telecom
Beiqijia Town, Changping District Beiqijia Town
Beijing 102209 Changping District
Beijing
102209
China China
Email: wangaj3@chinatelecom.cn Email: wangaj3@chinatelecom.cn
Acee Lindem Acee Lindem
Cisco Systems Cisco Systems, Inc.
301 Midenhall Way 301 Midenhall Way
Cary, NC 27513 Cary, NC 27513
USA United States of America
Email: acee@cisco.com Email: acee@cisco.com
Jie Dong Jie Dong
Huawei Technologies Huawei Technologies
Huawei Campus, No. 156 Beiqing Rd.
Beijing Beijing
100095
China China
Email: jie.dong@huawei.com Email: jie.dong@huawei.com
Peter Psenak Peter Psenak
Cisco Systems Cisco Systems, Inc.
Eurovea Centre, Central 3
Pribinova Street 10 Pribinova Street 10
Bratislava, Eurovea Centre, Central 3 81109 81109 Bratislava
Slovakia Slovakia
Email: ppsenak@cisco.com Email: ppsenak@cisco.com
Ketan Talaulikar (editor) Ketan Talaulikar (editor)
Cisco Systems Cisco Systems, Inc.
India India
Email: ketant@cisco.com Email: ketant@cisco.com
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