MultiKarma : a fully decentralized virtual multi-currency.

Participant-based technologies enable users to contribute resources to a shared pool that in the aggregate provides valuable services, such as social networks, massive multiplayer online games, file exchange, etc. Such systems depend on participant contribution; however, some peers may be unwilling to contribute at a level on par with their consumption. Monetary systems incentivize participation through compensation that allows portability, asynchronous participation, granularity and misbehavior costs. The use of government-backed currencies for incentive structures in participant-based systems results in exchange barriers and high transaction costs, while centralized virtual currencies (e.g., Facebook credits) remove many of the benefits of currency. Karma proposes the use of peer-to-peer systems to create a decentralized, consensus-based currency; however, it lacks a complete specification or implementation. We provide a specification, implementation, and evaluation of Karma. Next, we extend Karma to create a multi-currency system called MultiKarma where participants can mint, manage, and distribute their own currency.