I don't support adopting the draft at the moment. A stronger applicability statement and reducing the number of parameter sets would be steps in the right direction, but I'm a "not yet" because the motivating example seems to be DTLS. Unlike TLS, I'm not aware of any experiments using SLH-DSA in DTLS and I think there are still open questions about amplification attacks (https://eprint.iacr.org/2023/266) which are potentially much worse with SLH-DSA.
Peter > -----Original Message----- > From: Sean Turner <s...@sn3rd.com> > Sent: 25 July 2025 08:26 > To: TLS List <tls@ietf.org> > Subject: [TLS] Re: Second WG Adoption Call for Use of SLH-DSA in TLS 1.3 > > Hi! Just a reminder that this call closes on Monday. > > spt > > > On Jul 15, 2025, at 00:05, Sean Turner <s...@sn3rd.com> wrote: > > > > We kicked off an adoption call for Use of SLH-DSA in TLS 1.3; see [0]. We > called consensus [1], and that decision was appealed. We have reviewed the > messages and agree that we need to redo the adoption call to get more input. > > > > What appears to be the most common concern, which we will take from > Panos' email, is that "SLH-DSA sigs are too large and slow for general use in > TLS 1.3 applications". One way to address this concern is to add an > applicablity statement to address this point. We would like to propose that > this (or something close to this) be added to the I-D: > > > > Applications that use SLH-DSA need to be aware that the signatures sizes are > large; the signature sizes for the cipher suites specified herein range from > 7,856 to 49,856 bytes. Likewise, the cipher suites are considered slow. While > these costs might be amoritized over the cost of a long lived connection, the > cipher suites specified herein are not considered for general use in TLS 1.3. > > > > With this addition in mind, we would like to start another WG adoption call > for draft-reddy-tls-slhdsa. If you support adoption with the above text (or > something similar) and are willing to review and contribute text, please send > a message to the list. If you do not support adoption of this draft with the > above text (or something similar), please send a message to the list and > indicate why. This call will close at 2359 UTC on 28 July 2025. > > > > Cheers, > > Deirdre, Joe, and Sean > > > > [0] > https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmailarc > hive.ietf.org%2Farch%2Fmsg%2Ftls%2Fo4KnXjI- > OpuHPcB33e8e78rACb0%2F&data=05%7C02%7Cpeter.c%40ncsc.gov.uk%7C2 > 01c39c6390f4576286708ddcb4c9e26%7C14aa5744ece1474ea2d734f46dda64 > a1%7C0%7C0%7C638890252124042183%7CUnknown%7CTWFpbGZsb3d8eyJ > FbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiT > WFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=pKHJhIxCE1%2BWnwU > wbXT7ze1ACjY95T2MZg%2Fo315EjPs%3D&reserved=0 > > [1] > https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmailarc > hive.ietf.org%2Farch%2Fmsg%2Ftls%2FhhLtBBctK5em6l82m7rgM6_hefo%2F& > data=05%7C02%7Cpeter.c%40ncsc.gov.uk%7C201c39c6390f4576286708ddcb4 > c9e26%7C14aa5744ece1474ea2d734f46dda64a1%7C0%7C0%7C63889025212 > 4069084%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiO > iIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C > 0%7C%7C%7C&sdata=v6vIitoNnT1s2sYIN8GARL6e0DDV2gdI36%2FXaPsf4dM > %3D&reserved=0 > > [2] > https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdatatra > cker.ietf.org%2Fdoc%2Fdraft-reddy-tls- > slhdsa%2F&data=05%7C02%7Cpeter.c%40ncsc.gov.uk%7C201c39c6390f45762 > 86708ddcb4c9e26%7C14aa5744ece1474ea2d734f46dda64a1%7C0%7C0%7C6 > 38890252124080664%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOn > RydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ > %3D%3D%7C0%7C%7C%7C&sdata=0IFzKvjlnSxwi0Sm2nFB9%2BpezAqrADail0 > 7tqlShQyE%3D&reserved=0 > > _______________________________________________ > TLS mailing list -- tls@ietf.org > To unsubscribe send an email to tls-le...@ietf.org _______________________________________________ TLS mailing list -- tls@ietf.org To unsubscribe send an email to tls-le...@ietf.org
