| Invited Talk

Name of the Speaker: Mr. Srivatsan Sridhar
Name of the Organizer: Prof. Srikrishna Bhashyam
Venue: ESB-234 (Malaviya Hall)
Date/Time: 18th December 2024 (Wednesday), 11:00 AM
Title: New Models for Consensus in the Blockchain Era

Abstract :

The security of distributed systems often depends on the delay between one node sending a message and another node receiving and processing the message. How should we model this delay to prove the security of protocols? The commonly used bounded-delay model assumes that all messages are processed within a bounded delay. This neglects the fact that due to limited processing capacities, receiving many messages in a short time causes queuing delays. In this talk, I will discuss attacks on the consensus protocol powering major blockchains like Bitcoin and Cardano, exploiting queuing delays to overcome previously proven security bounds. Then, I will present a refined security analysis in a more realistic bounded-capacity model by using random walks and queues with adversarial arrivals. This talk is based on https://eprint.iacr.org/2021/1545 and https://eprint.iacr.org/2023/381.

Speaker Bio:

Mr. Srivatsan Sridhar