XPay: practical anonymous payments for tor routing and other networked services

Abstract

We design and analyze the first practical anonymous payment mechanisms for network services. We start by reporting on our experience with the implementation of a routing micropayment solution for Tor. We then propose micropayment protocols of increasingly complex requirements for networked services, such as P2P or cloud-hosted services. The solutions are efficient, with bandwidth and latency overheads of under 4% and 0.9 ms respectively (in ORPay for Tor), provide full anonymity (both for payers and payees), and support thousands of transactions per second.