Description of field of research:

Scalability is a major bottleneck for the adoption of Blockchains. Whereas Visa can process about 1800 transactions per second (TPS), blockchains like Bitcoin processes only 7 transactions and Ethereum 20 transactions per second respectively. To explain the reason, we look at the steps for settling a transaction. Once transactions are made, these are broadcasted in the networks. Specialised blockchain nodes (miners) collect these transactions, verify them, put a set of transactions in a block and broadcast the block in the network. Blockchains-peers come to a consensus regarding which block is to be added to blockchain. After this, the block is added to the ledger. In order to have confidence in the system peers maintain the entire copy of the ledger, which is a big storage overhead.

In order to design a good scaling solution, we need to understand how transaction data is organised and how do we verify that the transactions are correct. We plan to examine authenticated data structures which provide evidence if the transaction is correctly executed and recorded on the blockchain. The aim of the project is to advance the state-of-the-art in authenticated data structures that are efficient and will help scale blockchains to thousands of TPS.


Computer Science and Engineering

Research areas

Security, Cryptography, Data Structures, Algorithms, Blockchains

The supervisor is supportive and has very good understanding of the topic. She is currently studying variants of this problem. Some of these are in collaboration with her students and collaborators in Australia and abroad. She has worked with many undergraduate students some of whom went on to pursue a career in Security and Cryptography, including higher degrees like Ph. D. Some of the students even published their first research papers with her. The student will be mentored and nurtured to appreciate the beauty and power of cryptography. The student will also interact with other members of the cybersecurity group.

The student will understand how foundational problems are buried in practical problems. The student can use many of the tools and techniques they learnt in their Discrete Mathematics and data structure courses. Mathematical thinking and proof techniques will be explored. The student will appreciate to solve problems with an attacker;s mindset. The aim is to experience the joys of research.

Roberto Tamassia, Authenticated Data Structures.

Dan Boneh, Benedikt Bünz, and Ben Fisch. Batching Techniques for Accumulators with Applications to IOPs and Stateless Blockchains. In CRYPTO'19, 2019.