August 26, 2019

**<sarang>** All righty!

**<sarang>** Let's begin our meeting

**<sarang>** Agenda: https://github.com/monero-project/meta/issues/385

**<sarang>** Logs will be posted there after the meeting

**<sarang>** GREETINGS

**<rehrar>** hi

**<parasew[m]>** hello

**<suraeNoether>** good morning

**<sarang>** Let's move to ROUNDTABLE

**<sarang>** suraeNoether: care to go first?

**<suraeNoether>** sure, last week I made a commit to my buttercup branch with some matching algorithm fixes, which is now operating as far as i can tell 100% smoothly

**<sarang>** Nice! Looking forward to reviewing it

**<suraeNoether>** i also have the framework for a markov chain simulator of a basic ledger almost ready to push later today, which we will be using to identify best practices while churning, etc

**<suraeNoether>** in addition to that, I discovered a discrete distribution over the weekend that could be very helpful in working with output selection

**<suraeNoether>** that's pretty much it. not tremendously eventful, except the matching algo unit tests

**<sarang>** Will be neat to see if we can adjust output selection to such a distribution efficiently and robustly

**<sarang>** Low priority in the grand scheme of things, but intriguing nonetheless

**<sarang>** I am finishing preparation of the CLSAG paper for submission to Financial Cryptography 2020

**<hyc>** definitely, will be nice to have some exploration of churning that we can document

**<sarang>** PR 5707 has been updated to simplify the hashing code

**<suraeNoether>** oh, sarang and i decided we should also submit the thring signature paper to FinCrypt2020 also, sort of doubling our chances (but not really, it's nonlinear :P)

**<sarang>** Note that this removes `hashToPointSimple`

and moves its functionality directly into the relevant unit test

**<sarang>** `hashToPointSimple`

is only used to produce a Pedersen generator, but it's brittle on arbitrary input and not useful elsewhere

**<sarang>** (unless we updated how we do hash-to-points to use an iterated index, but this is not backwards-compatible)

**<sarang>** Additional eyes on PR 5707 would be welcome

**<sarang>** And: Stanford announced the dates and CFP of their next blockchain conference

**<sarang>** TBH it's probably not worth our time to submit a paper/presentation, given their acceptance rate

**<sarang>** Unless anyone has an idea for something something zero knowledge ethereum =p

**<sarang>** I kid, I kid

**<suraeNoether>** *cough*

**<suraeNoether>** but not

**<hyc>** lol

**<sarang>** Finally, I continue analysis work on proving systems

**<suraeNoether>** 5707 is for how the second basepoint in our pedersen commitments are selected. if i recall from my conversation with sarang earlier, this PR will make the monero codebase slightly more robust, less brittle, more consistent with the way it works, and more importantly *more easily verified to be correct* by new users, even though it's a relatively small change

**<sarang>** RingCT3.0 is exploitable in its current form, but I'm told a forthcoming fix likely solves the problem (unclear if provably at this point) with little impact on efficiency

**<sarang>** suraeNoether: the change only makes it harder to use the wrong hashing method :)

**<sarang>** and enables slightly more efficient hash-to-point operations under some constructions

**<sarang>** Anyway, a new preprint (IACR/944) discusses a new proving system for more general constraint systems

**<sarang>** And there will be a forthcoming preprint with a proving system on pairing groups, which simplifies cleanly to non-pairing groups too

**<sarang>** I've been looking over that one, since the authors graciously provided an advance copy

**<sarang>** What will be interesting is whether the Omniring prover relations can be efficiently moved into a more general proving system

**<sarang>** Making it easier (in theory) to do future changes

**<kenshamir[m]>** Could you comment on the computational complexity when you simplify the proving system to a non-pairing group?

**<sarang>** Eventually =p

**<sarang>** I've only just begun working through that paper

**<sarang>** FWIW I'm told the preprint is quite imminent

**<kenshamir[m]>** Ahh alright, any idea when it will be released?

**<sarang>** ^^

**<sarang>** Oh and suraeNoether: the primary purpose of 5707 is to speed up MLSAG by removing redundant operations… this led to simplifications of the available hashing operations as a side effect

**<suraeNoether>** thanks for correcting that! i didn't realize the larger scope (just started going through it)

**<sarang>** and at that point it seemed like a good idea to remove the brittle `hashToPointSimple`

and put it directly into the unit test that enables verification of how `H`

was derived

**<sarang>** There are two commits: the second commit moves the hash stuff around

**<sarang>** the first commit alters the MLSAG code

**<suraeNoether>** gotcha

**<sarang>** All righty

**<sarang>** Does anyone else wish to share interesting research work?

**<rehrar>** :/ if I were that smart, sure

**<sarang>** Don't underestimate yourself!

**<sarang>** While we're at it, we can also do GENERAL QUESTIONS for anyone

**<rehrar>** well, I did read a recent paper on hormesis as it relates to beetles.

**<sarang>** lol

**<rehrar>** my skills are not going to be helpful here :P

**<hyc>** oh, you just reminded me of that stream of tweets from Sarah Jamie Lewis yesterday, about ants and alarm pheromones

**<sarang>** Regarding CLSAG, the plan is to submit to several relevant conferences/journals (in sequence) and hope for acceptance

**<hyc>** the relevance was to illustrating how localized decision making can be gamed / subverted

**<sarang>** It falls into an awkward spot: it's a neat improvement on earlier work with good security model/proofs, but isn't profoundly new

**<sarang>** And unfortunately you can't do simultaneous submissions :/

**<hyc>** (and thus an argument why you need global consensus)

**<sarang>** The FC deadline is in September, with notification by November 15

**<hyc>** lots of stuff isn't profoundly new, but the imporvement still is worth talking about

**<sarang>** Yeah, but that's tough for publication

**<hyc>** maybe different forums then. heck, chip manufacturers give big presentations on ~5-10% gains

**<sarang>** Hence doing a fair bit of rewriting for better context

**<hyc>** cool. yes, expanding the scope of applicability is also a good angle

**<sarang>** and page limits (grumble grumble stupid wide margins)

**<sarang>** Aaaaanyway

**<sarang>** Perhaps on to ACTION ITEMS

**<sarang>** I have several, and I don't expect to complete them all this week

**<sarang>** CLSAG revisions, in preparation for submission

**<sarang>** My doctoral adviser always recommended putting down a paper for a week after your revisions, so you can revisit it with fresh eyes before submission

**<sarang>** Second is a better understanding of the reduction of this forthcoming proving system to non-pairing groups

**<sarang>** Third is going over suraeNoether's completed matching code

**<sarang>** Since suraeNoether had to step away for a few minutes, I assume his action items are applications of his test-passing matching code, and preparation of the thring signature paper for its submission (he can correct me later)

**<sarang>** Any last comments or questions or information from anyone?

**<sarang>** OK, we can adjourn! Thanks to everyone for joining in

**<sarang>** Logs will be posted shortly to the agenda issue

Post tags : Dev Diaries, Cryptography, Monero Research Lab