OSPF terminology update: Update to OSPF Terminology
Swaps the master/slave wording in OSPF for Leader/Follower across seven RFCs without changing how the protocol works.
Fox, M., Lindem, A., and A. Retana, "Update to OSPF Terminology", RFC 9454, DOI 10.17487/RFC9454, August 2023, <https://www.rfc-editor.org/info/rfc9454>.
@misc{rfc9454,
series = {Request for Comments},
number = 9454,
howpublished = {RFC 9454},
publisher = {RFC Editor},
doi = {10.17487/RFC9454},
url = {https://www.rfc-editor.org/info/rfc9454},
author = {M. Fox and A. Lindem and A. Retana},
title = {{Update to OSPF Terminology}},
pagetotal = 6,
year = 2023,
month = aug,
} RFC text
Contents
Internet Engineering Task Force (IETF) M. Fox
Request for Comments: 9454 IBM
Updates: 2328, 4222, 4811, 5243, 5340, 5614, A. Lindem
5838 LabN Consulting, L.L.C.
Category: Standards Track A. Retana
ISSN: 2070-1721 Futurewei Technologies, Inc.
August 2023
Update to OSPF Terminology
Abstract
This document updates some OSPF terminology to be in line with
inclusive language used in the industry. The IETF has designated
"Guidance for NIST Staff on Using Inclusive Language in Documentary
Standards" by the US National Institute of Standards and Technology
(NIST) for its inclusive language guidelines. It is intended that
all future OSPF documents use this revised terminology even when they
reference the RFCs updated by this document.
This document updates RFCs 2328, 4222, 4811, 5243, 5340, 5614, and
5838.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
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/rfc9454.
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. Introduction
2. Update to RFC 2328
3. Update to RFC 4222
4. Update to RFC 4811
5. Update to RFC 5243
6. Update to RFC 5340
7. Update to RFC 5614
8. Update to RFC 5838
9. IANA Considerations
10. Security Considerations
11. References
11.1. Normative References
11.2. Informative References
Acknowledgements
Authors' Addresses
1. Introduction
This document updates some OSPF terminology to be in line with
inclusive language used in the industry. The IETF has designated
"Guidance for NIST Staff on Using Inclusive Language in Documentary
Standards" by the US National Institute of Standards and Technology
(NIST) [NISTIR8366] for its inclusive language guidelines. It is
intended that all future OSPF documents use this revised terminology
even when they reference the RFCs updated by this document.
This document updates [RFC2328], [RFC4222], [RFC4811], [RFC5243],
[RFC5340], [RFC5614], and [RFC5838].
2. Update to RFC 2328
The base OSPFv2 specification "OSPF Version 2" [RFC2328] defines the
synchronization of databases as two routers forming a "master/slave"
relationship. All instances of these terms are replaced by "Leader/
Follower", respectively.
In the Database Description packet, the "master (MS) bit" is renamed
the "Leader (L) bit".
The operation of OSPFv2 is not modified. The Leader/Follower
terminology and Leader (L) bit definition changes impact the
following sections: "The Synchronization of Databases" (Section 7.2),
"The Neighbor Data Structure" (Section 10), "Neighbor states"
(Section 10.1), "Events causing neighbor state changes"
(Section 10.2), "The Neighbor state machine" (Section 10.3),
"Receiving Database Description Packets" (Section 10.6), "Sending
Database Description Packets" (Section 10.8), "An Example"
(Section 10.10), and "The Database Description packet"
(Appendix A.3.3).
3. Update to RFC 4222
"Prioritized Treatment of Specific OSPF Version 2 Packets and
Congestion Avoidance" [RFC4222] is a Best Current Practice (BCP)
document. In Appendix C, Item (2), there is an example OSFPv2 packet
sequence that refers to the "slave" in a database exchange; this
reference is renamed to "Follower".
4. Update to RFC 4811
"OSPF Out-of-Band Link State Database (LSDB) Resynchronization"
[RFC4811] is an Informational document. Section 2.4 includes a
Database Description packet (Figure 2) and a description of the
attendant encoding changes for Out-of-Band Resynchronization. In the
figure and the description, all instances of "MS" (when referring to
the Database Description packet bit) are renamed to "L". There is
also a reference to "Master" in this section that is renamed to
"Leader".
5. Update to RFC 5243
"OSPF Database Exchange Summary List Optimization" [RFC5243] is an
Informational document. The Introduction (Section 1) references
"Master or Slave"; this is replaced by "Leader or Follower".
Section 3 includes an example of the optimized database exchange. In
this example, all instances of "Master" and "Slave" are renamed to
"Leader" and "Follower", respectively.
6. Update to RFC 5340
The base OSPFv3 specification "OSPF for IPv6" [RFC5340] defines the
Database Description process between two routers as one being
"designated to be the master and the other is the slave". All
instances of these terms are replaced by "Leader/Follower",
respectively.
In the Database Description packet, the "Master/Slave (MS) bit" is
renamed the "Leader (L) bit".
The operation of OSPFv3 is not modified. The Leader/Follower
terminology and Leader (L) bit definition changes impact "The
Database Description Packet" (Appendix A.3.3).
7. Update to RFC 5614
"Mobile Ad Hoc Network (MANET) Extension of OSPF Using Connected
Dominating Set (CDS) Flooding" [RFC5614] is an Experimental document.
"Changes to the Neighbor State Machine" (Section 7.1) contains
modifications to the neighbor state machine that were updated from
[RFC2328]. In the neighbor state machine modifications, all
instances of "Master" and "Slave" are renamed to "Leader" and
"Follower", respectively. Additionally, all instances of "MS" (when
referring to the Database Description packet bit) are renamed to "L".
And in "Receiving Database Description Packets" (Section 7.5),
"master or slave" is replaced by "Leader or Follower" in the
parenthetical.
8. Update to RFC 5838
"Support of Address Families in OSPFv3" [RFC5838] is a Standards
Track document. "Database Description Maximum Transmission Unit
(MTU) Specification for Non-IPv6 AFs" (Section 2.7) contains a
Database Description packet change figure that includes the MS bit.
In this figure, the "MS" field is renamed the "L" field.
Additionally, in the first paragraph of "Changes to the Hello Packet
Processing" (Section 2.4), the text is updated to remove the non-
inclusive terms pertaining to unreachability handling as follows:
| When an OSPFv3 router does not support this specification and an
| interface is configured with the Instance ID corresponding to an
| IPv4 AF, packets could be routed toward this interface and
| dropped. This could happen due to misconfiguration or a router
| software downgrade. For example, an IPv4 packet could be received
| on an interface not supporting IPv4 since a router that doesn't
| support this specification can still include the interface in an
| SPF-calculated path as long as it establishes adjacencies using
| the Instance ID corresponding to the IPv4 AF. Note that OSPFv3
| Router-LSAs and Network-LSAs are AF-agnostic.
9. IANA Considerations
In the "Database Description (DD) Packet Flags" registry, IANA has
updated the description for value 0x01 to "Leader (L-bit)" and has
added this document as a reference, as shown below.
Value: 0x01
Description: Leader (L-bit)
Reference: [RFC2328] [RFC9454]
10. Security Considerations
This document updates the terminology used in OSPF RFCs without any
modification to the specifications of the protocol. As such, the
security characteristics of OSPF do not change.
11. References
11.1. Normative References
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998,
<https://www.rfc-editor.org/info/rfc2328>.
[RFC4222] Choudhury, G., Ed., "Prioritized Treatment of Specific
OSPF Version 2 Packets and Congestion Avoidance", BCP 112,
RFC 4222, DOI 10.17487/RFC4222, October 2005,
<https://www.rfc-editor.org/info/rfc4222>.
[RFC4811] Nguyen, L., Roy, A., and A. Zinin, "OSPF Out-of-Band Link
State Database (LSDB) Resynchronization", RFC 4811,
DOI 10.17487/RFC4811, March 2007,
<https://www.rfc-editor.org/info/rfc4811>.
[RFC5243] Ogier, R., "OSPF Database Exchange Summary List
Optimization", RFC 5243, DOI 10.17487/RFC5243, May 2008,
<https://www.rfc-editor.org/info/rfc5243>.
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
for IPv6", RFC 5340, DOI 10.17487/RFC5340, July 2008,
<https://www.rfc-editor.org/info/rfc5340>.
[RFC5614] Ogier, R. and P. Spagnolo, "Mobile Ad Hoc Network (MANET)
Extension of OSPF Using Connected Dominating Set (CDS)
Flooding", RFC 5614, DOI 10.17487/RFC5614, August 2009,
<https://www.rfc-editor.org/info/rfc5614>.
[RFC5838] Lindem, A., Ed., Mirtorabi, S., Roy, A., Barnes, M., and
R. Aggarwal, "Support of Address Families in OSPFv3",
RFC 5838, DOI 10.17487/RFC5838, April 2010,
<https://www.rfc-editor.org/info/rfc5838>.
11.2. Informative References
[NISTIR8366]
National Institute of Standards and Technology (NIST),
"Guidance for NIST Staff on Using Inclusive Language in
Documentary Standards", NIST Interagency/Internal Report
(NISTIR) 8366, April 2021,
<https://doi.org/10.6028/NIST.IR.8366>.
Acknowledgements
Thanks to Dhruv Dhody, Adrian Farrel, Erik Kline, and Barry Leiba for
their reviews and comments.
Authors' Addresses
Mike Fox
IBM
3039 E Cornwallis Rd.
Research Triangle Park, NC 27709
United States of America
Email: mjfox@us.ibm.com
Acee Lindem
LabN Consulting, L.L.C.
301 Midenhall Way
Cary, NC 27513
United States of America
Email: acee.ietf@gmail.com
Alvaro Retana
Futurewei Technologies, Inc.
2330 Central Expressway
Santa Clara, CA 95050
United States of America
Email: aretana@futurewei.com
AI ELI5
On this page
§1Why the Terms Changed
RFC 9454 updates some OSPF terminology to be in line with inclusive language used in the industry. The IETF designated the NIST document "Guidance for NIST Staff on Using Inclusive Language in Documentary Standards" as its inclusive language guideline.
The RFC intends that all future OSPF documents use the revised terminology, even when they reference the RFCs it updates. It updates seven documents: RFC 2328, RFC 4222, RFC 4811, RFC 5243, RFC 5340, RFC 5614 and RFC 5838.
People agreed some old words should be replaced. This note lists which words change and in which books, so everyone uses the same new words from now on.
§2Master/Slave Becomes Leader/Follower
The base OSPFv2 specification, RFC 2328, describes database synchronization as two routers forming a master/slave relationship. All instances of these terms are replaced by Leader and Follower. In the Database Description packet, the master (MS) bit becomes the Leader (L) bit.
The RFC states that the operation of OSPFv2 is not modified. The change touches the sections on synchronization of databases, the neighbor data structure, neighbor states, events causing neighbor state changes, the neighbor state machine, receiving and sending Database Description packets, an example, and the Database Description packet format in Appendix A.3.3.
OSPFv3, in RFC 5340, gets the same treatment. Its "Master/Slave (MS) bit" is renamed the Leader (L) bit, only the Database Description packet appendix is affected, and operation is again unchanged.
When two routers compare notes, one used to be called the boss and one the helper. Now they are the Leader and the Follower. The way they take turns has not changed at all.
| Old term | New term |
|---|---|
| master | Leader |
| slave | Follower |
| master (MS) bit THIS RFC | Leader (L) bit |
§3Other Documents Touched
Five more RFCs get smaller edits:
- RFC 4222, a Best Current Practice document: the "slave" in an example packet sequence in Appendix C becomes "Follower".
- RFC 4811, Informational: in Section 2.4, "MS" for the Database Description bit becomes "L", and "Master" becomes "Leader".
- RFC 5243, Informational: "Master or Slave" in the Introduction and all uses in the Section 3 example become Leader and Follower.
- RFC 5614, Experimental: the neighbor state machine changes and the Section 7.5 parenthetical use the new terms and the "L" bit name.
- RFC 5838, Standards Track: the "MS" field in a Database Description figure becomes "L".
RFC 5838 also gets one rewritten paragraph in its Section 2.4 on Hello packet processing. The new text about an interface configured for an IPv4 address family removes the non-inclusive terms pertaining to unreachability handling.
Other books mention the same old words in examples and pictures. Each one gets a small list of corrections, and one paragraph is rewritten.
§4IANA Registry Update
IANA updated the "Database Description (DD) Packet Flags" registry. The description for value 0x01 is now "Leader (L-bit)", and the references are RFC 2328 and RFC 9454.
The flag keeps the same value. Only its name and description change, which matches the RFC's statement that protocol behavior is untouched.
The official list of flag names got the new label, but the flag still sits in the same slot and does the same job.
§5Security Considerations
The RFC says it updates terminology in OSPF RFCs without any modification to the specifications of the protocol. As a result, the security characteristics of OSPF do not change.
Implementers do not need to alter message processing, only names used in documentation, and where applicable in the registry entry.
Because only the names changed, nothing about how safe OSPF is has changed either.