Serge Vaudenay
<<Invited Talk>>
〇 Date: 2025.4.24 (Thu.)
〇 Speaker: Serge Vaudenay (Swiss Federal Institute of Technology Lausanne, EPFL)
〇 Title: Fair Exchange
〇 Abstract
Designing an efficient fair exchange protocol is a long lasting problem. It is known to be impossible without a third party.
The advent of smart contract technology offers a platform for having a transparent immutable trusted third party, which enables fair exchange.
When focusing on the problem of exchanging a deterministically verifiable digital item against a payment in crypto-currency,
two families of protocols have arisen: ZK-based ones and optimistic ones.
The former requires heavy computations while the latter requires complicated dispute resolution.
We propose a new protocol in the optimistic family which improves the state of the art.
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<<Invited Talk>>
〇 Date: 2019.2.4 (Mon.)
〇 Speaker: Serge Vaudenay (Swiss Federal Institute of Technology Lausanne, EPFL)
〇 Title: Secure Communication by Ratcheting
〇 Abstract
There has been an increasing interest in post-compromise security, due to mass surveillance.
One technique to address this security is called ratcheting.
In this presentation, we summarize recent developments in provably secure ratcheted communication
and show that we need more efficient protocols.
We further present our latest result on how to construct efficient protocols by clearly identifying the desired security.
