Dear COSE WG, First of all, thank you for the interest in our Ascon over COSE and JOSE draft during IETF 123 meeting. Ascon is finally released so the draft looks even more pertinent now [1].
After the meeting we kept working on the draft and now we are ready to show you the new version of it [2]. Our thanks to Christian Amsüss, who gave us his vision on the draft development which we readily agree with. Since the last version we made the following changes: 1. Introduced 3 variations of Ascon-AEAD128 for COSE with 128-, 64-, and 32-bit tags correspondingly. As Christian suggested, 32-bit tag is introduces for extremely constrained use-cases and is marked as "Filter Only" to prevent unjustified use. 2. Introduced 2 variations of Ascon-AEAD128 for JOSE with 128-, 64-bit tags. No 32-bit tag option here, since JOSE is not meant to be used in extremely constrained environments. 3. Updated the examples for COSE and JOSE with Ascon-AEAD128. For the examples we used our custom implementation for cose with Ascon and jose with Ascon in C. For that we: 1. Used ascon-c implementation [3]. 2. Forked COSE-C repository and integrated Ascon library with it [4]. 3. Forked jose repository and integrated Ascon with it [5]. 4. Came up with some basic examples using these libraries. Still there are a bunch of points to agree upon: 1. Does these Ascon-AEAD128 variations look relevant for everyone? What about the naming and number assignments? 2. Are the examples clear for everyone? Any improvements to be done here? 3. For now there is no notion of Ascon-Hash256 in the draft. We would like to know if there is a consensus to introduce it within this draft as well. Our opinion is that Ascon-Hash256 deserves a place in COSE, especially, because it uses the same permutations as Ascon AEAD. 4. Need to make sure there is also interest for this draft within JOSE WG. If not, we don't mind removing JOSE part since we prioritize COSE. We are looking forward to the feedback on this topic and are open to any discussions. Best regards, Dmytro P.S. For those who are interested to see some performance evaluation data on Ascon [6]. [1] - https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-232.pdf [2] - https://datatracker.ietf.org/doc/draft-ochkas-cose-ascon/ [3] - https://github.com/ascon/ascon-c [4] - https://github.com/cose-wg/COSE-C [5] - https://github.com/latchset/jose [6] - I. Elsadek et al., "State-of-the-Art ASCON ASIC Achieving 4.3 Gbps@0.8V and 3.5Tb/J@0.6V Outperforming AES by 25 Times," in IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 72, no. 8, pp. 4021-4030, Aug. 2025, doi: 10.1109/TCSI.2024.3522193. _______________________________________________ COSE mailing list -- cose@ietf.org To unsubscribe send an email to cose-le...@ietf.org
