This Week in Blockchain Research Issue #87
|zk Capital||Dec 16, 2020|
Paper of the Week:
A polynomial commitment scheme (PCS) provides the ability to commit to a polynomial over a finite field and prove its evaluation at points. A succinct PCS has commitment and evaluation proof size sublinear in the degree of the polynomial. An efficient PCS has sublinear proof verification. Recently, it has been shown that any efficient and succinct PCS can be used to construct a SNARK with similar security and efficiency characteristics.
This work defines an additive PCS to capture a “homomorphic” property of commitments over a computational group G of bounded size. All existing examples of additive schemes (e.g., Bulletproofs, KZG, DARK, Dory) are also what are called m-spanning, meaning that commitments to the monomials of degree less than m generate G.
The first technical result is a black-box transformation of any m-spanning additive PCS into a hiding PCS with a zero-knowledge evaluation proof. The second technical result is that every additive succinct PCS supports efficient proof aggregation.
PCS proof aggregation reduces the task of proving evaluations of multiple commitments at multiple independent points to the task of proving the evaluation of a single “aggregate” commitment at a single point.
Two flavors of aggregation are presented: private and public. In private aggregation the prover has a private witness consisting of openings of the input commitments. In public aggregation, the prover/verifier share the same inputs, which includes non-interactive evaluation proofs for each input commitment.
The public aggregation protocol applies to any additive succinct PCS. The private aggregation protocol applies more broadly to any succinct PCS that supports an efficient linear combination scheme: a protocol for verifiably aggregating commitments into a new commitment to their linear combination. This includes non-additive schemes such as the post-quantum FRI-based PCS.
These results are applied to the Halo proof carrying data (PCD) system. This work shows that Halo can be instantiated with any PCS that supports efficient PCS aggregation, private or public. Thus, the results show that efficient (zero-knowledge) SNARKs and PCD can be constructed from any succinct PCS that has an efficient linear combination scheme, even if the PCS itself is inefficient.
1. Paper Title: Foundations of Ring Sampling.
Summary: An analytical model of ring samplers towards a deeper understanding of them through systematic studies.
Authors: Viktoria Ronge*, Christoph Egger*, Russell W. F. Lai*, Dominique Schröder*, and Hoover H. F. Yin†,
2. Paper Title: SoK: Diving into DAG-based Blockchain Systems.
Summary: Consolidated core knowledge of the structural shift in blockchain systems and a review of the state-of-the-art DAG-based blockchain systems with comprehensive mechanisms and properties.
Authors: Qin Wang*,§, Jiangshan Yu†, Shiping Chen‡, and Yang Xiang*,
Summary: A survey to investigate the integration of blockchain with services computing.
Summary: A secure payment routing hub that is fully feasible without the hub’s deposit.
Affiliations: * Seoul National University.
Check out paper of the week.
1. Paper Title: DeFi and the Future of Finance.
Summary: Decentralized finance provides compelling advantages over traditional finance along the verticals of decentralization, access, efficiency, interoperability, and transparency.
Authors: Campbell R. Harvey*, Ashwin Ramachandran†, and Joey Santoro†,
Affiliations: * Duke University and † Independent.
Summary: From characterizing our present public-private franchise system of payment and finance, through explaining how it came to be and why it was destined never to be more than a way-station en route to full citizen-managed money and finance, to describing in detail that better and final destination.
Authors: Robert C. Hockett*,
Affiliations: * Cornell University.
3. Paper Title: Proposing Cybersecurity Regulations for Smart Contracts.
Summary: This paper summarizes the concept of smart contracts while providing the background and context of its development.
Authors: Raffi Teperdjian*,
Affiliations: * George Washington University.
Conferences, Journals, & CFPs:
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