Subject: [mpls] [Errata Held for Document Update] RFC7307 (5145)

From: RFC Errata System <[email-masked]>
Date: Fri, 26 Feb 2021 14:11:56 -0800 (PST)

The following errata report has been held for document update 
for RFC7307, "LDP Extensions for Multi-Topology". 

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You may review the report below and at:
https://www.rfc-editor.org/errata/eid5145

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Status: Held for Document Update
Type: Editorial

Reported by: Sandra Murphy <[email-masked]>
Date Reported: 2017-10-05
Held by: Deborah Brungard (IESG)

Section: 4.3.2

Original Text
-------------
   The format of this sub-TLV is similar to the LDP IPv4 FEC sub-TLV as
   defined in [RFC4379].  In addition to "IPv4 prefix" and "Prefix
   Length" fields, this new sub-TLV also specifies the MT-ID (Multi-
   Topology ID).  The Length for this sub-TLV is 5.

Corrected Text
--------------
   The format of the MT LDP IPv4 prefix sub-TLV (type 31) is similar to
   the LDP IPv4 prefix sub-TLV (type 1) as defined in [RFC4379].  In
   addition to the "IPv4 prefix" and "Prefix Length" fields already
   defined in the LDP IPv4 prefix sub-TLV, the new MT LDP IPv4 prefix
   sub-TLV also specifies the MT-ID (Multi-Topology ID) field.  While
   the length of the LDP IPv4 prefix sub-TLV is 5 (and does not include
   the trailing MBZ bytes), the length of this new MT LDP IPv6 prefix 
   sub-TLV is 8 (and does include the internal MBZ byte).

Notes
-----
The original text uses "this sub-TLV" in ways that can be ambiguous. In particular, the final sentence "The Length for this sub-TLV is 5." is incorrect if "this sub-TLV" refers to the topic of the section, i.e., "MT LDP IPv4 FEC Sub-TLV", but is correct if "this sub-TLV" refers to the LDP IPv4 prefix sub-TLV defined in RFC4379/RFC8029. The revised text is suggested to remove the ambiguities. Adrian Farrell provided the bulk of the suggested revisions.

In addition, the sub-TLV names are changed to match the names that were registered in the IANA registry, to aid those trying to find the registry entries.

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RFC7307 (draft-ietf-mpls-ldp-multi-topology-12)
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Title               : LDP Extensions for Multi-Topology
Publication Date    : July 2014
Author(s)           : Q. Zhao, K. Raza, C. Zhou, L. Fang, L. Li, D. King
Category            : PROPOSED STANDARD
Source              : Multiprotocol Label Switching
Area                : Routing
Stream              : IETF
Verifying Party     : IESG