No abstract

The Tor Darknet is a pseudo-anonymous place to host content online frequently used by criminals to sell narcotics and to distribute illicit material. Many studies have attempted to estimate the size of the darknet, but this paper will show that previous estimates on size are inaccurate due to hidden service lifecycle. The first examination of its kind will be presented on the differences between short-lived and long-lived hidden services. Finally, in light of a new Tor protocol for the darknet which will prevent the running of relays to learning darknet sites, an analysis is presented of the use of crawling and whether this is an effective mechanism to discover sites for law enforcement.

No abstract

This paper presents a possible solution to a fundamental limitation facing all blockchain-based systems; scalability. We propose a temporal "rolling" blockchain which solves the problem of its current exponential growth, instead replacing it with a constant fixed-size blockchain. We conduct a thorough analysis of related work and present a formal analysis of the new rolling blockchain, comparing the results to a traditional blockchain model to demonstrate that the deletion of data from the blockchain does not impact on the security of the proposed blockchain model before concluding our work and presenting future work to be conducted.

The Tor anonymity network allows users to protect their privacy and circumvent censorship restrictions but also shields those distributing child abuse content, selling or buying illicit drugs, or sharing malware online. Using data collected from Tor entry nodes, we provide an estimation of the proportion of Tor network users that likely employ the network in putatively good or bad ways. Overall, on an average country/day, ∼6.7% of Tor network users connect to Onion/Hidden Services that are disproportionately used for illicit purposes. We also show that the likely balance of beneficial and malicious use of Tor is unevenly spread globally and systematically varies based upon a country’s political conditions. In particular, using Freedom House’s coding and terminological classifications, the proportion of often illicit Onion/Hidden Services use is more prevalent (∼7.8%) in “free” countries than in either “partially free” (∼6.7%) or “not free” regimes (∼4.8%).