[IPsec] Re: [EXT] [Pqc] Re: Re: [EXTERNAL] PQC integration in IPsec/IKEv2 - implementation experience and interop

[Songbo Bu <[e-mail]>]

Hi Nick, Paul, Uri, all,

I took a first pass at the starter matrix I mentioned and attached it as
Markdown.

It is deliberately lightweight: not an interop claim, and not a
standards-status statement. The goal is just to give implementers a common
row format for recording what was actually tested, against which peer, and
with what evidence. I also split KEM-based authentication into its own
bucket after Uri’s note, rather than folding it into RFC 9370 or PQC
signature authentication.

The seed rows are only placeholders based on the public discussion so far.
They should be replaced or corrected by the actual implementers if the
group wants to use this around IETF 126 / hackathon coordination.

Best,
Songbo

On Tue, 23 Jun 2026 02:27:19 +0000, “Blumenthal, Uri - 0553 - MITLL”
[e-mail] wrote:

Please add this draft to the list of mechanisms:

https://datatracker.ietf.org/doc/draft-wang-ipsecme-kem-auth-ikev2/

–

V/R,

Uri Blumenthal

There are two ways to design a system. One is to make it so simple there
are obviously no deficiencies.

The other is to make it so complex there are no obvious deficiencies.

   - C. A. R. Hoare

I was a shepherd to fools

Causelessly bold or afraid.

They would not abide by my rules.

Yet they escaped. For I stayed.

R. Kipling “Epitaphs of the War. Convoy Escort”

From: Songbo Bu [e-mail]
Date: Monday, June 22, 2026 at 21:23
To: [e-mail] [e-mail]; [e-mail] [e-mail]
Cc: [e-mail] [e-mail]; [e-mail] [e-mail]
Subject: [EXT] [Pqc] Re: [IPsec] Re: [EXTERNAL] PQC integration in
IPsec/IKEv2 - implementation experience and interop

This Message Is From an External Sender

This message came from outside the Laboratory.

Hi Nick, Paul, all,

This thread is useful.

I agree with Paul that IPsec/IKEv2 interop probably does not need a
QUIC-style continuous public test harness to be useful.

A lower-friction artifact may be enough for the first pass: a public
interop checklist and results matrix that records exactly what was tested,
against which peer, and what evidence was observed.

For PQC-in-IKEv2 I would split the first matrix along a few axes:

   -

   implementation and version;
   -

   peer implementation and version;
   -

   deployment shape: site-to-site, remote access, or point-to-point;
   -

   mechanism: RFC 8784 PPK, RFC 9867 PPK with IKE_INTERMEDIATE, RFC 9370
   multiple key exchange, PQC authentication, reliable IKEv2 transport,
   downgrade prevention;
   -

   algorithm set: ML-KEM and ML-DSA parameter sets actually exercised;
   -

   path conditions: fragmentation, retransmission, NAT traversal,
   rekey/CREATE_CHILD_SA, and failure diagnostics;
   -

   result evidence: packet trace summary, logs, negotiated transforms, and
   failure reason where applicable.

That would let vendors and open-source implementations participate at
different disclosure levels while still producing useful compatibility data.

If there is interest, I can help turn this into a starter checklist or
markdown matrix for the IETF 126 hackathon discussion.

Best,
Songbo

On Mon, 22 Jun 2026 19:26:21 -0400 (EDT), Paul Wouters [e-mail] wrote:

On Mon, 22 Jun 2026, Nick Grifka wrote:

Also, I see in the past there have been PQC-related interop events (ex:
https://github.com/IETF-Hackathon/pqc-certificates) Is there any appetite
for an interop
event for PQC in IPsec/IKEv2 amongst the community? I realize the nature of
many IPsec/IKEv2 products might not be suitable for a robust and efficient
interop
framework (ex: https://github.com/quic-interop) so maybe that makes such
an event less practical.

Traditionally these were held in the past (called “bake offs” but then
IPR got into the way of that name). But since IKEv2/IPsec has strong
opensource releases (libreswan and strongswan), interop testing usually
happens against those implementations (and recently elvis-plus) and doesn’t
require much gathering. Although if you will be at IETF-126, there will
be *swan people and elvis-plus people who will gladly do some interop
testing with you - especially during the hackathon days (Sat+Sun)

Paul