Florian Tschorsch

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—Tor is a distributed onion-routing network used for achieving anonymity and resisting censorship online. Because of Tor's growing popularity, it is attracting increasingly larger threats against which it was not securely designed. In this paper, we present the Sniper Attack, an extremely low cost but highly destructive denial of service attack against Tor(More)
Besides attracting a billion dollar economy, Bitcoin revolutionized the field of digital currencies and influenced many adjacent areas. This also induced significant scientific interest. In this survey, we unroll and structure the manyfold results and research directions. We start by introducing the Bitcoin protocol and its building blocks. From there we(More)
Internet anonymity systems, like for instance Tor, are in widespread use today. Technically they are realized as overlays, i. e., they add another instance of routing, forwarding, and transport functionality on top of the Internet protocol stack. This has important (and often subtle) implications, as overlay and underlay may interact. Far too often,(More)
—Location management is a key component of cellular networks. From a privacy perspective, however, it is also a major weakness: location management empowers the network operator to track users. In today's public and scientific discussion, the centralized storage of location data is mostly taken as a fact, and users are expected to trust the network(More)
Tor has become the prime example for anonymous communication systems. With increasing popularity, though, Tor is also faced with increasing load. In this paper, we tackle one of the fundamental problems in today's anonymity networks: network congestion. We show that the current Tor design is not able to adjust the load appropriately , and we argue that(More)