[Resource Topic] 2020/723: On the Confidentiality of Amounts in Grin

Welcome to the resource topic for 2020/723

On the Confidentiality of Amounts in Grin

Authors: Suyash Bagad, Saravanan Vijayakumaran


Pedersen commitments have been adopted by several cryptocurrencies for hiding transaction amounts. While Pedersen commitments are perfectly hiding in isolation, the cryptocurrency transaction rules can reveal relationships between the amounts hidden in the commitments involved in the transaction. Such relationships can be combined with the public coin creation schedule to provide upper bounds on the number of coins in a commitment. In this paper, we consider the Grin cryptocurrency and derive upper bounds on the number of coins which can be present in regular transaction outputs. In a March 2020 snapshot of the Grin blockchain, we find that out of the 110,149 unspent regular transaction outputs 983 of them have less than 1800 grin (number of coins typically minted in half an hour) stored in them. On the other hand, 95% of the unspent regular transaction outputs in the snapshot have an upper bound which is at least 90% of the total Grin supply at their respective block heights. We conclude that while our method does not violate the confidentiality of the amounts in most of the outputs on the Grin blockchain, the amounts in some outputs can be estimated to be in a narrow range.

ePrint: https://eprint.iacr.org/2020/723

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .