CS Colloquium - Philipp Jovanovic

Event time: 
Wednesday, April 3, 2019 - 4:00pm
AKW 200 See map
51 Prospect Street
New Haven, CT 06511
Event description: 

CS Colloquium - Philipp Jovanovic

Refreshments available at 3:45

Host: Zhong Shao and Ruzica Piskac

Title: Towards Privacy-preserving, Scalable, Digital Trust Systems


The history of the Internet serves as an inspiration on how much value can be created when building systems on top of open and neutral protocols but also as a warning that centralizing trust and power in a small number of organizations might turn into an existential threat to the democratic foundations of our society.

To address this dilemma and return to a more balanced trust model, we need to develop tools that help to reduce dependencies on trusted intermediaries and spread power more widely, that facilitate collaboration between mutually distrustful parties in a scalable way, and that protect the privacy of involved participants. Getting there is by no means trivial, however, due to a vast number of challenges we face in the design and development of these technologies.

In this talk, I discuss novel cryptographic tools that address some of the privacy and scalability challenges in that context. The first part is dedicated to privacy where I highlight the challenges in developing and deploying secure authenticated encryption (AE) schemes, the standard tool to protect in-transit data, by discussing a broken AE construction used in the widely deployed Open Smart Grid Protocol. Afterwards, I introduce the Masked Even-Mansour (MEM) tweakable block cipher and show how it can be utilized to construct MEM-AE, a family of novel, side-channel resilient, secure authenticated encryption schemes, belonging to the fastest symmetric ciphers to date. In the second part of the talk, I turn to scalability and present RandHound and RandHerd two new cryptographic protocols enabling to generate publicly verifiable, unbiasable randomness in a distributed and scalable way. As a concrete application example, I show how these randomness protocols can be used to realize highly scalable, distributed ledgers that achieve scale-out throughput and are able to rival the performance of legacy payment networks like Visa.


Philipp Jovanovic is a Post-Doctoral Researcher at École polytechnique fédérale de Lausanne (EPFL), Switzerland. Before joining EPFL, he received his PhD in Computer Science from the University of Passau, Germany, in 2015.

His research interests broadly include applied cryptography, information security, privacy, and decentralized systems and his recent work involves improving scalability, security, and privacy of distributed ledger systems. Besides this line of research, he has also worked on a wide variety of other security-related topics, including design and analysis of symmetric cryptographic primitives, side-channel attacks and countermeasures, hardware Trojans, or the security analysis of protocols deployed in the real world such as TLS or the Open Smart Grid Protocol.