FG Distributed Security Infrastructures (DSI)

6 Items

Recent Submissions
Exploring Deployment Strategies for the Tor Network

Döpmann, Christoph ; Rust, Sebastian ; Tschorsch, Florian (2018)

In response to upcoming performance and security challenges of anonymity networks like Tor, it will be of crucial importance to be able to develop and deploy performance improvements and state-of-the-art countermeasures. In this paper, we therefore explore different deployment strategies and review their applicability, impact, and risks to the Tor network. In a simulation-based evaluation, whic...

Towards a Concurrent and Distributed Route Selection for Payment Channel Networks

Rohrer, Elias ; Laß, Jann-Frederik ; Tschorsch, Florian (2017)

Payment channel networks use off-chain transactions to provide virtually arbitrary transaction rates. In this paper, we provide a new perspective on payment channels and consider them as a flow network. We propose an extended push-relabel algorithm to find payment flows in a payment channel network. Our algorithm enables a distributed and concurrent execution without violating capacity constrai...

Webchain: Verifiable Citations and References for the World Wide Web

Rohrer, Elias ; Heidel, Steffen ; Tschorsch, Florian (2018)

Readers’ capability to consider and assess sources is imperative. Digital preservation efforts, however, mostly neglected citation provenance, which is a necessity for transparent source verification. We therefore present Webchain, a new system enabling verifiable citations and references on the World Wide Web. Its architecture combines a distributed ledger with secure timestamping to ensure hi...

CircuitStart: A Slow Start For Multi-Hop Anonymity Systems

Döpmann, Christoph ; Tschorsch, Florian (2018)

In order to improve the performance of anonymity networks like Tor, custom transport protocols have been proposed to efficiently deal with the multi-hop nature of such overlay networks. In this work, we tackle the issue of quickly, but safely, ramping up the congestion window during the initial phase of a circuit's lifetime. We propose a tailored startup mechanism called CircuitStart that trans...

P2KMV: A Privacy-preserving Counting Sketch for Efficient and Accurate Set Intersection Cardinality Estimations

Sparka, Hagen ; Tschorsch, Florian ; Scheuermann, Björn (2018-05-01)

In this paper, we propose P2KMV, a novel privacy-preserving counting sketch, based on the k minimum values algorithm. With P2KMV, we offer a versatile privacy-enhanced technology for obtaining statistics, following the principle of data minimization, and aiming for the sweet spot between privacy, accuracy, and computational efficiency. As our main contribution, we develop methods to perform set...

Exploring Deployment Strategies for the Tor Network [Extended Version]

Döpmann, Christoph ; Rust, Sebastian ; Tschorsch, Florian (2018-07-07)

In response to upcoming performance and security challenges of anonymity networks like Tor, it will be of crucial importance to be able to develop and deploy performance improvements and state-of-the-art countermeasures. In this paper, we therefore explore different deployment strategies and review their applicability to the Tor network. In particular, we consider flag day, dual stack, translat...