Talks and presentations
See a map of all the places I've given a talk!
July 16, 2024
Invited Talk, The 29th Australasian Conference on Information Security and Privacy (ACISP 2024), Sydney, Australia
Matrix multiplication is a common operation in applications like machine learning and data analytics. To demonstrate the correctness of such an operation in a privacy-preserving manner, we propose zkMatrix, a zero-knowledge proof for the multiplication of committed matrices. Among the succinct non-interactive zero-knowledge protocols that have an O(log n) transcript size and O(log n) verifier time, zkMatrix stands out as the first to achieve O(n^2) prover time and O(n^2) RAM usage for multiplying two n×n matrices. Significantly, zkMatrix distinguishes itself as the first zk-SNARK protocol specifically designed for matrix multiplication. By batching multiple proofs together, each additional matrix multiplication only necessitates O(n) group operations in prover time.
June 04, 2018
Invited Talk, Second ACM Workshop on Blockchains, Cryptocurrencies and Contracts (BCC'18), Incheon, Korea
Blockchain provides an immutable, global transaction history in distributed system. All transactions can be seen by all of the nodes on the network. However, it may not be desirable in business use cases that require strong privacy. In public blockchain, several cryptographic techniques are used to provide anonymity of users and confidentiality of transaction amount (such as linkable ring signature in Monero, and zk-SNARK in ZCash). However, they are not efficient enough for systems with high throughput. Therefore, we propose and implement some new privacy-enhancing techniques which can be used in consortium blockchain.
December 13, 2017
Invited Talk, 13th International Conference on Information Security Practice and Experience (ISPEC), Melbourne, Australia
Blockchain, the core component of Bitcoin, has been extremely popular among the finance, supply chain and many other industries in the last few years. Many governments and companies are experimenting blockchain with proof of concepts. The growing interest in blockchain drives a lot of new security research areas, including security model and analysis of blockchain, consensus algorithms built from cryptographic primitives, privacy enhancing technologies in blockchain (e.g. linkable ring signatures, zk-SNARKs), etc. There are still some gap between the research community and the blockchain applications. In this talk, we will introduce some challenges we faced, such as implementation difficulties, research problems and application level challenges. We present our views and some solutions on these issues.
