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PhD Proposal: Saad Quader
November 20, 2019 @ 12:00 pm - 1:00 pm UTC-5
Title: Security analysis of Proof-of-Stake blockchains
PhD Candidate: Saad Quader
Major Advisor: Dr. Alex Russell
Associate Advisors: Dr. Benjamin Fuller, Dr. Walter Krawec
Day/Time: Wednesday, November 20, 2019 12:00-1:00 PM
Location: HBL Video Theatre 2
Abstract:
The security analysis of blockchain protocols embodies a confluence of elegant mathematical ideas from cryptography, combinatorics, and stochastic analysis. In this dissertation proposal, we use these techniques to tackle some important open problems in the analysis of “proof-of-stake” (PoS) blockchains.
We set the stage by treating the consistency property of PoS blockchains (SODA 2020). Specifically, we showed that honest players in PoS protocols can agree about the past, except with probability 2^{-k}, by discarding a suffix of length O(k) from their locally-held chains; the previous state-of-the-art guarantee was O(k^2).
As an ongoing work, we carefully study the situation where multiple honest blocks are issued in a single time-slot. Our preliminary results directly improve the security assumptions in PoS blockchains. In an orthogonal direction, we tackle the “grinding attack” where an adversarial coalition tries to influence the outcomes of future events by biasing the collectively-generated random bits inside the protocol.
Our treatment of PoS blockchains provides more realistic and accurate models for the security of proof of stake blockchains, allowing practitioners to be more informed about threats.
