On Feb 18, 2026, at 2:50 AM, Peter Psenak <[email protected]>
wrote:
Hi Alice,
please see inline (##PP):
On 17/02/2026 01:30, [email protected] wrote:
Authors,
While reviewing this document during AUTH48, please resolve (as necessary) the
following questions, which are also in the source file.
1) <!-- [rfced] Please insert any keywords (beyond those that appear in
the title) for use on https://www.rfc-editor.org/search. -->
2) <!--[rfced] Please clarify this sentence. Specifically, please make the
statements about OSPFv2 and OSPFv3 parallel. Is is accurate that the first
two mechanisms are for OSPFv2, and the last one is for OSPFv3?
Original:
In OSPFv2 using the cost of MaxLinkMetric for all
non-stub links in the router-LSA [RFC6987], or H-bit [RFC8770], and
R-bit for OSPFv3 [RFC5340] are mechanisms available for that purpose.
Perhaps:
The mechanisms available for that purpose are (in OSPFv2) using the cost
of MaxLinkMetric for all non-stub links in the router-LSA [RFC6987] or using
the H-bit [RFC8770], or (in OSPFv3 [RFC5340]) using the R-bit.
-->
##PP
Ack
3) <!--[rfced] Please clarify item 1.
Original:
1. Reachability of a prefix that was reachable earlier was lost.
Perhaps:
1. A prefix that was reachable earlier is now lost (i.e., no longer
reachable).
-->
##PP
I would prefer:
"A prefix that was reachable earlier becomes unreachable"
4) <!--[rfced] Please clarify item 2. Why is the first item "if"?
Is the second item dependent on the first "if" clause? If so, we
suggest putting them together.
Original:
2. For any of the planned maintenance cases:
- if the node originating the prefix is signalling the
overload state in IS-IS, or or H-bit in OSPFv2 [RFC8770], or
R-bit in OSPFv3 [RFC5340] .
- the metric to reach the prefix from an ABR or ASBR crosses
the configured threshold.
Perhaps:
For any of the planned maintenance cases, if the node originating the
prefix is signaling the overload state in IS-IS, or is using the H-bit
in OSPFv2 [RFC8770] or the R-bit in OSPFv3 [RFC5340], then the metric
to reach the prefix from an ABR or ASBR crosses the configured
threshold.
-->
##PP
no, above is not right.
- please keep it as two independent statements
- please remove the "if" in the first statement
5) <!--[rfced] Should this be plural "databases"?
Original:
Not withdrawing the UPA would result in
stale information being kept in the link state database of all
routers in the area.
Perhaps:
Not withdrawing the UPA would result in
stale information being kept in the link state databases of all
routers in the area.
##PP
Above is fine, please use that.
Or rephrase:
Withdrawing the UPA prevents the LSDB from holding stale
information about all routers in the area.
-->
6) <!--[rfced] Does "preceding section" refer to Section 2 or Section 3? We
suggest updating the text to use the section number.
Original (Section 3.1):
As per the definitions referenced in the preceding section, any
prefix advertisement with a metric value ...
Perhaps:
As per the definitions referenced in Section 3, any
prefix advertisement with a metric value ...
-->
##PP
Ack.
7) <!-- [rfced] How may this paragraph be rephrased for clarity?
Original (Section 3.2):
In IS-IS a prefix can be advertised with metric higher than
0xFE000000, for various reasons. Even though in all cases the
treatment of such metric is specified for IS-IS, having an explicit
way to signal that the prefix was advertised in order to signal UPA
is required to distinguish it from other cases where the prefix with
such metric is advertised.
Perhaps:
In IS-IS, a prefix can be advertised with a metric higher than
0xFE000000, for various reasons.
While IS-IS specifies the treatment of such metrics, explicit
signaling is required to distinguish UPA from other high-metric
advertisements.
-->
##PP
Ack
8) <!--[rfced] Similarly, how may this paragraph be rephrased for clarity?
Original (Section 4.2):
In OSPFv2 a prefix can be advertised with metric LSInfinity, or in
OSPFv3 with NU-bit set in PrefixOptions, for various reasons. Even
though in all cases the treatment of such metric, or NU-bit, is
specified for OSPFv2 and OSPFv3, having an explicit way to signal
that the prefix was advertised in order to signal UPA is required to
distinguish it from other cases where the prefix with such metric is
advertised.
Perhaps:
A prefix can be advertised (in OSPFv2) with the LSInfinity metric or
(in OSPFv3) with the NU-bit set in PrefixOptions, for various reasons.
While OSPFv2 and OSPFv3 specify the treatment of the LSInfinity metric
and the NU-bit, explicit signaling is required to distinguish UPA
from other scenarios using the LSInfinity metric or NU-bit.
-->
##PP
Ack
9) <!--[rfced] FYI, we updated this TLV name to match the name used in the
IANA Considerations. Please let us know if this is not accurate.
Original: Prefix Attributes Sub-TLV
Current: Prefix Attribute Flags Sub-TLV
-->
##PP
Ack
10) <!--[rfced] Please clarify this sentence, in particular the opening phrase.
Original:
For default algorithm 0
prefixes with U-Flag it is therefore REQUIRED to advertise the
unreachable prefix in the base OSPFv2 LSA - e.g., OSPFv2 Summary-LSA
[RFC2328], or AS-external-LSAs [RFC2328], or NSSA AS-external LSA
[RFC3101].
Perhaps:
Therefore, for the default algorithm 0 with prefixes advertised with U-Flag,
it is REQUIRED to advertise the
unreachable prefix in the base OSPFv2 LSA - e.g., OSPFv2 Summary-LSA
[RFC2328], AS-external-LSAs [RFC2328], or NSSA AS-external LSA
[RFC3101].
##PP
We need to correct the initial sentence of that section to include both new
bits:
So the entire section should read as:
"The prefix that is advertised with U-Flag or UP-Flag MUST have the metric set
to a value LSInfinity.
If the prefix metric is not equal to LSInfinity, both of these flags MUST be
ignored. Therefore, for the prefixes in default algorithm 0 that are advertised with
U-Flag, or Up-Flag, it is REQUIRED to advertise the unreachable prefix in the base
OSPFv2 LSA - e.g., OSPFv2 Summary-LSA [RFC2328], AS-external-LSAs [RFC2328], or NSSA
AS-external LSA [RFC3101]."
Regarding a similar phrase in Section 4.2.2, may it be updated as follows?
Original:
For default algorithm 0 prefixes,
the LSInfinity MUST be set in the parent TLV.
Perhaps:
For prefixes in default algorithm 0,
the LSInfinity MUST be set in the parent TLV.
##PP
Above sounds good.
Or:
When advertising prefix reachability in default algorithm 0,
the LSInfinity MUST be set in the parent TLV.
-->
11) <!-- [rfced] Do you want to keep these TLV names as they are, or change to
match how they appear in RFC 8362?
This document:
Intra-Area Prefix TLV
Inter-Area Prefix TLV
External Prefix TLV
[RFC8362] and the corresponding IANA registry
(https://www.iana.org/assignments/ospfv3-parameters/ospfv3-parameters.xhtml#extended-lsa-tlvs)
use the following (with an additional hyphen in each):
Intra-Area-Prefix TLV
Inter-Area-Prefix TLV
External-Prefix TLV
-->
##PP
Please use the RFC8362 naming as you suggested above.
12) <!-- [rfced] Please review the "Inclusive Language" portion of the online
Style Guide <https://www.rfc-editor.org/styleguide/part2/#inclusive_language>
and let us know if any changes are needed. Updates of this nature typically
result in more precise language, which is helpful for readers.
Please consider whether "traditionally" should be updated for clarity.
While the NIST website
<https://web.archive.org/web/20250214092458/https://www.nist.gov/nist-research-library/nist-technical-series-publications-author-instructions#table1>
indicates that this term is potentially biased, it is also ambiguous.
"Traditionally" is a subjective term, as it is not the same for everyone.
-->
##PP
please remove the "traditionally" from the text.
thanks, Peter
Thank you.
Alice Russo
RFC Production Center
