Private and secure mixing in credit networks

Abstract

In this paper, we propose a system for mixing transactions in payment networks such as credit networks. Credit networks like Ripple and Stellar are increasingly popular, and can facilitate crosscurrency transactions in a fraction of the time it would take for banks or other financial institutions to process the same transaction, and at a fraction of the cost. Unlike for cryptocurrencies, there has been little work in the area of designing secure and private mixers for credit networks. Mixers for cryptocurrencies such as Bitcoin cannot be directly applied to the credit network domain because credit networks have an inherently different structure and purpose than cryptocurrencies. We design a system that uses cryptographic constructs such as ring signatures, commitments, and zero knowledge proofs to provide security/integrity of all transactions, ensures privacy of the users involved in a transaction, as well as privacy of the amount transacted. We also provide preliminary experimental results.