Generic Group Model

Statements set in a generic group model (Shoup’s or Maurer’s), where the adversary accesses group operations only through an oracle.

Status Statement Tags
dv-SNARG, One Group Element
Numbered Conjecture 1.3 of the source. Its own theorems achieve one group element plus O(tau) bits, and (with a random oracle) one group element, one hash output and about 2 tau bits; the conjecture halves the additive term to tau + o(tau) and asks for no random oracle. 4 open
Generic Group ModelProof Size Lower BoundsSnarksggmcharacterization
Four-party NIKE, quadratic, Maurer’s model
Open. Achieved in Shoup’s generic group model by the source paper (Construction 9, Theorem 10); in Maurer’s model the paper’s own O(n^2) attack sets a ceiling that a construction would meet exactly, and nothing is known about reaching it. 5 open
Generic Group ModelNon Interactive Key Exchangeggmseparation
Quadratic attack on 3-NIKE, Shoup’s model
Open in Shoup’s model. Settled by the source paper in Maurer’s model for every K at least 3, including imperfect correctness; its own three-party Shoup construction achieves only an n^1.5 gap, so the truth for three parties lies somewhere between n^1.5 and n^2. 5 open
Generic Group ModelNon Interactive Key Exchangeggmlower-bound
Optimal 2D LPHS
Open, and asserted rather than asked: the source prints the algorithm, conjectures the error rate, reports experiments consistent with it, states it could not analyse it, and leaves settling it to future work. The matching lower bound is the source’s own theorem, so a proof would close the two-dimensional case exactly. 7 open
Distributed Discrete LogarithmGeneric Group ModelLocality Preserving Hashingtight-boundadaptation (ai)
r-round DLOG tradeoff
Open for every intermediate r: the r = 1 endpoint is the source’s own theorem and r = T is Corrigan-Gibbs–Kogan, with nothing proved in between. The source conjectures the interpolating formula and says a matching attack exists at every r, so the missing half is the lower bound. 6 open
AdaptivityDiscrete LogarithmGeneric Group ModelTime Space Tradeoffsggmtight-bound
No 2-element split NILPs
A submitted construction gives a two-element split NILP for Boolean circuit satisfiability in the plain generic Type-III bilinear-group model; proof review and formalization remain open. 2 open
Generic Group ModelProof Size Lower BoundsSnarksimpossibilityresearch-solved
No round-optimal pairing-free blind signature
Open for a polynomial query budget. The impossibility is proved when User_2 and Verify together make O(log lambda) random-oracle queries, including when oracle outputs contain group elements; the superpolynomial message space hypothesis is retained. 5 open
Black Box SeparationsBlind SignaturesGeneric Group ModelSignature Schemesggmimpossibilityadaptation (ai)
Non-adaptive DDH bound
Open, and asserted rather than asked: the source proves 1/2 + O~(T^2/N + sqrt(ST/N)), states twice that it conjectures this is not tight for DDH, and names 1/2 + O~(T^2/N + ST/N) as the right answer. The same theorem’s square-DDH bound is sharp, with a matching attack, which is what makes the DDH case a question rather than a suspicion. 6 open
AdaptivityDiscrete LogarithmGeneric Group ModelTime Space Tradeoffsggmtight-boundadaptation (ai)
No matching items