Traveling the Silk Road: A measurement analysis of a large anonymous online marketplace (CMU-CyLab-12-018)
We perform a comprehensive measurement analysis of Silk Road, an anonymous, international online marketplace that operates as a Tor hidden service and uses Bitcoin as its exchange currency. We gather and analyze data over eight months between the end of 2011 and 2012, including daily crawls of the marketplace for nearly six months in 2012. We obtain a detailed picture of the type of goods being sold on Silk Road, and of the revenues made both by sellers and Silk Road operators. Through examining over 24,400 separate items sold on the site, we show that Silk Road is overwhelmingly used as a market for controlled substances and narcotics. A relatively small “core” of about 60 sellers has been present throughout our measurement interval, while the majority of sellers leaves (or goes “underground”) within a couple of weeks of their first appearance. We evaluate the total revenue made by all sellers to approximately USD 1.9 million per month; this corresponds to about USD 143,000 per month in commissions perceived by the Silk Road operators. We further show that the marketplace has been operating steadily, with daily sales and number of sellers overall increasing over the past few months. We discuss economic and policy implications of our analysis and results, including ethical considerations for future research in this area.