15 Sep 2021 | Updated 19 Sep 2021 [research]

Monero community torn between Seraphis/Lelantus Spark and Triptych

Between the various topics discussed during today’s Monero Research Lab meeting1, the Seraphis/Lelantus Spark vs Triptych debate was arguably the most intriguing.

Lelantus Spark2 is the successor of Lelantus v1/v2. Most of the work is credited to Aram Jivanyan from Firo3’s research team and Aaron Feickert from Cypher Stack4. Aaron is on a full time contract with Firo.

The mere mention of Firo/CypherStack seems to have brought back flashbacks to previous controversies5, at least for some people:

Who is behind this project ? There’s a lot of “Firo” in the PDF, makes me wonna throw up to be honest..6

Is monero copying the technology from firo????7

During the MRL irc meeting, sentiment appeared to shift in favor of switching to Seraphis rather than continuing to pursue Triptych, but the community still had a lot of questions.

One of the biggest concerns is that XMR users would need to get new Lelantus Spark/Seraphis addresses. This could impact users, vendors and the general UX.

Although newly generated addresses wouldn’t be affected, the address format change would effectively render previously widely published static addresses (donations, address book, etc) effectively unusable/invalid.

UkoeHB8 has been working on a PoC for Seraphis for the past couple of weeks and with the protocol still in the experimental stage and not implemented yet, the more eyes on it, the better for everyone. He shares some insight into the positives of Seraphis over Triptych:

[..] membership proof delegation (allows tx chaining, offloading membership proofs to third parties, reduces timing analysis of slow tx like multisig), collaborative funding (multiple funders for a tx without big crypto design effort), better address schemes (several variations)

If Seraphis/etc. turn out to be flops, Triptych is the best known protocol.9

coinstudent204810 has put together a technical report11 on Seraphis. He has been working on Seraphis’s security proofs and is looking for community feedback for his formalization of the security properties12.

The community hasn’t yet reached consensus in this matter, but both Triptych and Seraphis are at least a year + out13 in the future.

We will know more after the next few meetings:

  1. https://github.com/monero-project/meta/issues/610, https://libera.monerologs.net/monero-research-lab/20210915 

  2. https://ia.cr/2021/1173, https://yewtu.be/watch?v=vEZC1fTYRZk (video) 

  3. https://firo.org/ 

  4. https://www.cypherstack.com/ 

  5. /rehrar-removed-core-team/ 

  6. https://libredd.it/r/Monero/comments/posi9i/lelantus_spark_secure_and_flexible_private/hcyv7s3/?context=3 

  7. https://libredd.it/r/Monero/comments/posi9i/lelantus_spark_secure_and_flexible_private/hcyzoku/?context=3 

  8. https://github.com/UkoeHB/monero/tree/seraphis_perf 

  9. https://libera.monerologs.net/monero-research-lab/20210915#c27831 

  10. https://github.com/coinstudent2048 

  11. https://raw.githubusercontent.com/coinstudent2048/writeups/main/seraphis.pdf 

  12. https://github.com/UkoeHB/Seraphis/issues/2#issuecomment-918639450 

  13. https://libera.monerologs.net/monero-research-lab/20210915#c27791, https://libera.monerologs.net/monero-research-lab/20210915#c27805 

  14. irc://irc.libera.chat/#monero-community (irc), https://matrix.to/#/#monero-community:monero.social (matrix) 

  15. irc://irc.libera.chat/#monero-dev (irc), https://matrix.to/#/#monero-dev:matrix.org (matrix)