# Nummatus: A Privacy Preserving Proof of Reserves Protocol for Quisquis

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## Abstract

Quisquis is a recently proposed design for a privacy-focused cryptocurrency. We present *Nummatus*, a privacy preserving proof of reserves protocol for Quisquis. Nummatus enables exchanges to create a Pedersen commitment to the amount of Quisquis coins they own, without revealing the exact accounts they own. These commitments can be combined with a commitment to the total liabilities of an exchange to generate a proof of solvency. The Nummatus protocol also facilitates detection of account sharing collusion between exchanges. Our simulations show that the cost of using Nummatus instead of a non-private proof of reserves protocol is not prohibitive.

## Keywords

Proof of reserves Quisquis Cryptocurrency Privacy in blockchain## References

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