Am I correct in understanding you to be saying that existing practice is to 
ignore this necessary security practice, and that is why it can't be added now 
as a MUST?

That makes things worse, not better ...

I hear you on the question of whether this draft is the right place to fix 
this, but it does certainly sound like something that needs to be fixed ...

-Tim


________________________________
From: Samuel Sidor (ssidor) <[email protected]>
Sent: Monday, March 16, 2026 3:24 AM
To: Ketan Talaulikar <[email protected]>; Tim Hollebeek 
<[email protected]>
Cc: Tim Hollebeek <[email protected]>; [email protected] 
<[email protected]>; [email protected] 
<[email protected]>; [email protected] 
<[email protected]>; [email protected] <[email protected]>
Subject: Re: draft-ietf-pce-circuit-style-pcep-extensions-15 ietf last call 
Secdir review

Hi Tim,

I agree with Ketan that this draft is probably not the best vehicle for such 
change. If we really (considering state of existing implementations) want to 
enforce it now, then I personally prefer to do it in separate document, which 
can cover other aspects (e.g. motivation behind such change in detail - not 
just for this specific extension, discuss alternative solutions and why those 
may not be sufficient, impact on existing implementations,...).

Regards,
Samuel

From: Ketan Talaulikar <[email protected]>
Date: Saturday, 14 March 2026 at 07:37
To: Tim Hollebeek <[email protected]>
Cc: Tim Hollebeek <[email protected]>, Samuel Sidor 
(ssidor) <[email protected]>, [email protected] <[email protected]>, 
[email protected] 
<[email protected]>, [email protected] 
<[email protected]>, [email protected] <[email protected]>
Subject: Re: draft-ietf-pce-circuit-style-pcep-extensions-15 ietf last call 
Secdir review

Hi Tim,

I don't disagree with your intent and motivation on this aspect. The question 
is whether this document that introduces a very specific extension is the place 
to do this.

The PCE WG is on this thread and I hope they get this message.

AFAIK the progress on "PCEPS" implementations has been slow but I now see some 
movement that gives me some optimism.

Thanks,
Ketan


On Fri, Mar 13, 2026 at 11:47 PM Tim Hollebeek 
<[email protected]<mailto:[email protected]>> wrote:
Actually, that would put a Requirement in the Considerations section, which is 
generally a bad idea. But I think you get my gist, if TLS is a requirement for 
doing this securely, I would like to see a way found to put that MUST 
requirement into the draft, so that people MUST do the right thing.

-Tim
________________________________
From: Tim Hollebeek 
<[email protected]<mailto:[email protected]>>
Sent: Friday, March 13, 2026 1:10 PM
To: Samuel Sidor (ssidor) <[email protected]<mailto:[email protected]>>; 
[email protected]<mailto:[email protected]> 
<[email protected]<mailto:[email protected]>>
Cc: 
[email protected]<mailto:[email protected]>
 
<[email protected]<mailto:[email protected]>>;
 [email protected]<mailto:[email protected]> 
<[email protected]<mailto:[email protected]>>; 
[email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>>
Subject: [secdir] Re: draft-ietf-pce-circuit-style-pcep-extensions-15 ietf last 
call Secdir review

Is there a reason why it can't continue ", and therefore TLS MUST be used in 
these situations." ?

If not, I agree your proposal is an improvement and support it.

-Tim


________________________________
From: Samuel Sidor (ssidor) <[email protected]<mailto:[email protected]>>
Sent: Thursday, March 12, 2026 4:23 AM
To: Tim Hollebeek 
<[email protected]<mailto:[email protected]>>; 
[email protected]<mailto:[email protected]> 
<[email protected]<mailto:[email protected]>>
Cc: 
[email protected]<mailto:[email protected]>
 
<[email protected]<mailto:[email protected]>>;
 [email protected]<mailto:[email protected]> 
<[email protected]<mailto:[email protected]>>; 
[email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>>
Subject: Re: draft-ietf-pce-circuit-style-pcep-extensions-15 ietf last call 
Secdir review

Hi Tim,

Thanks for the review and for the comment raised.

The security section structure follows the standard pattern used across other 
PCEP drafts/RFCs, e.g. RFC 8231, RFC 8281, RFC 8664, RFC 9357, … These use 
similar references to the base security considerations from existing RFCs. That 
is intentional: those documents, especially RFC 8253 and RFC 8231, already 
cover the security requirements for PCEP sessions in detail, and we don't want 
to duplicate or potentially contradict them.

I think the valid part of your comment is the concern about the connection 
between the specific threat we described and the mitigation. The draft does 
both — paragraph 2 explicitly calls out the new vulnerability (an attacker 
could manipulate PATH-MODIFICATION flags to block path updates, causing a 
traffic drop), and paragraph 3 describes the mitigation (use TLS per RFC 
8253/RFC 9325).

But I can still make it more explicit:

As per RFC 8231, it is RECOMMENDED that these PCEP extensions can only be 
activated on authenticated and encrypted sessions across PCEs and PCCs 
belonging to the same administrative authority, using Transport Layer Security 
(TLS) [RFC8253][I-D.ietf-pce-pceps-tls13] as per the recommendations and best 
current practices in [RFC9325]. In particular, the integrity protection 
provided by TLS mitigates the attack described above where an attacker could 
manipulate path modification constraints to cause a traffic disruption.

Would that work for you?

Thanks,
Samuel

From: Tim Hollebeek via Datatracker <[email protected]<mailto:[email protected]>>
Date: Wednesday, 11 March 2026 at 21:57
To: [email protected]<mailto:[email protected]> 
<[email protected]<mailto:[email protected]>>
Cc: 
[email protected]<mailto:[email protected]>
 
<[email protected]<mailto:[email protected]>>,
 [email protected]<mailto:[email protected]> 
<[email protected]<mailto:[email protected]>>, 
[email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>>
Subject: draft-ietf-pce-circuit-style-pcep-extensions-15 ietf last call Secdir 
review

Document: draft-ietf-pce-circuit-style-pcep-extensions
Title: Path Computation Element Communication Protocol (PCEP) extensions for
Circuit Style Policies Reviewer: Tim Hollebeek Review result: Has Issues

I'm not exactly an expert in routing, but I'm a bit concerned about the
security considerations section. If my understanding of the descriptions of the
security issues is correct, there are a variety of other complicated RFCs whose
security considerations sections need to be read and considered carefully.
There's a fair amount of subtlety, and it seems fairly easy to make mistakes
with serious consequences. This is not entirely obvious without diving into the
referenced security considerations.

Perhaps the section could be expanded with better guidance about what choices
implementers need to make to avoid introducing problems when implementing this
RFC. I'm concerned that the existing RECOMMENDATION might be easily missed,
with unfortunate consequences.


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